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Document and Entity Information - USD ($)	12 Months Ended
Document and Entity Information - USD ($)	Apr. 30, 2020	Jun. 23, 2020	Oct. 31, 2019
Document And Entity Information
Entity Registrant Name	Ocean Power Technologies, Inc.
Entity Central Index Key	0001378140
Document Type	10-K
Document Period End Date	Apr. 30, 2020
Amendment Flag	false
Current Fiscal Year End Date	--04-30
Entity a Well-known Seasoned Issuer	No
Entity a Voluntary Filer	No
Entity's Reporting Status Current	Yes
Entity Interactive Data Current	Yes
Entity Filer Category	Non-accelerated Filer
Entity Small Business Flag	true
Entity Emerging Growth Company	false
Entity Shell Company	false
Entity Public Float			$ 9,300,000
Entity Common Stock, Shares Outstanding		17,120,565
Document Fiscal Period Focus	FY
Document Fiscal Year Focus	2020

Consolidated Balance Sheets - USD ($) $ in Thousands	Apr. 30, 2020	Apr. 30, 2019
Current assets:
Cash and cash equivalents	$ 10,002	$ 16,660
Restricted cash- short-term	707	344
Accounts receivable	105	63
Contract assets	251	15
Other current assets	588	537
Total current assets	11,653	17,619
Property and equipment, net	499	592
Right-of-use asset, net	1,165
Restricted cash- long-term	221	155
Total assets	13,538	18,366
Current liabilities:
Accounts payable	220	312
Accrued expenses	1,353	1,938
Current portion of contract liabilities	100	188
Warrant liabilities		6
Right-of-use liability- current	229
Total current liabilities	1,902	2,444
Right-of-use liability	1,078
Long term portion of contract liabilities	65
Deferred rent		147
Total liabilities	3,045	2,591
Commitments and contingencies (Note 15)
Stockholders' Equity:
Preferred stock, $0.001 par value; authorized 5,000,000 shares, none issued or outstanding
Common stock, $0.001 par value; authorized 100,000,000 shares, issued 12,939,420 and 5,425,517 shares, respectively	13	5
Treasury stock, at cost; 4,251 and 3,770 shares, respectively	(302)	(301)
Additional paid-in capital	231,101	226,026
Accumulated deficit	(220,136)	(209,784)
Accumulated other comprehensive loss	(183)	(171)
Total stockholders' equity	10,493	15,775
Total liabilities and stockholders' equity	$ 13,538	$ 18,366

Consolidated Balance Sheets (Parenthetical) - $ / shares	Apr. 30, 2020	Apr. 30, 2019
Statement of Financial Position [Abstract]
Preferred stock, par value	$ 0.001	$ 0.001
Preferred stock, shares authorized	5,000,000	5,000,000
Preferred stock, shares issued
Preferred stock, shares outstanding
Common stock, par value	$ 0.001	$ 0.001
Common stock, shares authorized	100,000,000	100,000,000
Common stock, shares issued	12,939,420	5,425,517
Treasury stock, shares	4,251	3,770

Consolidated Statements of Operations - USD ($) $ in Thousands	12 Months Ended
	Apr. 30, 2020	Apr. 30, 2019
Income Statement [Abstract]
Revenues	$ 1,682	$ 632
Cost of revenues	1,787	1,303
Gross loss	(105)	(671)
Operating expenses:
Engineering and product development costs	4,344	4,984
Selling, general and administrative costs	6,916	7,616
Total operating expenses	11,260	12,600
Operating loss	(11,365)	(13,271)
Gain due to the change in fair value of warrant liabilities	6	195
Interest income, net	124	35
Foreign exchange loss	(12)	(55)
Loss before income taxes	(11,247)	(13,096)
Income tax benefit	895	850
Net loss	$ (10,352)	$ (12,246)
Basic and diluted net loss per share	$ (1.44)	$ (9.52)
Weighted average shares used to compute basic and diluted net loss per share	7,209,732	1,286,727

Consolidated Statements of Comprehensive Loss - USD ($) $ in Thousands	12 Months Ended
	Apr. 30, 2020	Apr. 30, 2019
Statement of Comprehensive Income [Abstract]
Net loss	$ (10,352)	$ (12,246)
Foreign currency translation adjustment	(12)	(11)
Total comprehensive loss	$ (10,364)	$ (12,257)

- Definition

Amount after tax of increase (decrease) in equity from transactions and other events and circumstances from net income and other comprehensive income. Excludes changes in equity resulting from investments by owners and distributions to owners.

+ References + Details

- Definition

The portion of profit or loss for the period, net of income taxes, which is attributable to the parent.

+ References

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+ Details

Consolidated Statements of Stockholders' Equity - USD ($) $ in Thousands	Common Shares [Member]	Treasury Shares [Member]	Additional Paid-In Capital [Member]	Accumulated Deficit [Member]	Accumulated Other Comprehensive Loss [Member]	Total
Balance at Apr. 30, 2018	$ 1	$ (300)	$ 208,233	$ (197,538)	$ (160)	$ 10,236
Balance, shares at Apr. 30, 2018	921,247	(3,701)
Net loss				(12,246)		(12,246)
Stock based compensation			295			295
Issuance (forfeiture) of restricted stock, net
Issuance (forfeiture) of restricted stock, net, shares	(5,090)
Exercise of prefunded warrants, net of issuance costs	$ 3		17			20
Exercise of prefunded warrants, net of issuance costs shares	2,632,120
Common stock issued for commitment fee- Aspire			295			295
Common stock issued for commitment fee- Aspire, shares	21,429
Issuance of common stock- Aspire financing, net of issuance costs			593			593
Issuance of common stock- Aspire financing, net of issuance costs, shares	162,162
Issuance of common stock- AGP At The Market offering, net of issuance costs			882			882
Issuance of common stock- AGP At The Market offering, net of issuance costs, shares	151,561
Issuance of common stock, common and pre-funded warants, net of issuance costs	$ 1		15,711			15,712
Issuance of common stock, common and pre-funded warants, net of issuance costs, shares	1,542,000
Acquisition of treasury stock		$ (1)				(1)
Acquisition of treasury stock, shares		(89)
Other comprehensive loss					(11)	(11)
Other
Other, shares	88	20
Balance at Apr. 30, 2019	$ 5	$ (301)	226,026	(209,784)	(171)	15,775
Balance, shares at Apr. 30, 2019	5,425,517	(3,770)
Net loss				(10,352)		(10,352)
Stock based compensation			340			340
Issuance (forfeiture) of restricted stock, net
Issuance (forfeiture) of restricted stock, net, shares	64,928
Exercise of prefunded warrants, net of issuance costs	$ 1		(17)			(16)
Exercise of prefunded warrants, net of issuance costs shares	753,560
Common stock issued for commitment fee- Aspire	$ 1		294			295
Common stock issued for commitment fee- Aspire, shares	194,805
Issuance of common stock- Aspire financing, net of issuance costs	$ 1		1,020			1,021
Issuance of common stock- Aspire financing, net of issuance costs, shares	1,399,205
Issuance of common stock- AGP At The Market offering, net of issuance costs	$ 5		3,438			3,443
Issuance of common stock- AGP At The Market offering, net of issuance costs, shares	5,101,405
Acquisition of treasury stock		$ (1)				(1)
Acquisition of treasury stock, shares		(481)
Other comprehensive loss					(12)	(12)
Balance at Apr. 30, 2020	$ 13	$ (302)	$ 231,101	$ (220,136)	$ (183)	$ 10,493
Balance, shares at Apr. 30, 2020	12,939,420	(4,251)

Consolidated Statements of Cash Flows - USD ($) $ in Thousands	12 Months Ended
	Apr. 30, 2020	Apr. 30, 2019
Cash flows from operating activities:
Net loss	$ (10,352)	$ (12,246)
Adjustments to reconcile net loss to net cash used in operating activities:
Foreign exchange loss	12	55
Depreciation of fixed assets	158	180
Amortization of right of use asset	197
Compensation expense related to stock option grants and restricted stock	340	295
Gain due to the change in fair value of warrant liabilities	(6)	(195)
Changes in operating assets and liabilities:
Accounts receivable	(42)	108
Unbilled receivables		71
Contract assets	(236)	(15)
Other assets	251	325
Accounts payable	(92)	23
Accrued expenses	(585)	(316)
Deferred rent		5
Deferred credit payable		(600)
Unearned revenue		(18)
Change in lease liability	(201)
Contract liabilities	(23)	188
Net cash used in operating activities	(10,579)	(12,140)
Cash flows from investing activities:
Purchases of marketable securities		(25)
Maturities of marketable securities		50
Purchase of computers, equipment and furniture	(65)	(54)
Net cash used in investing activities	(65)	(29)
Cash flows from financing activities:
Proceeds from issuance of common stock, common and pre-funded warrants, net of issuance costs		15,712
Proceeds from issuance of common stock- Aspire financing net of issuance costs	1,021	593
Proceeds from issuance of common stock- AGP At The Market offering, net of issuance costs	3,443	882
Proceeds (costs) associated with exercise of pre-funded warrants	(16)	20
Payment of capital lease obligations		(23)
Acquisition of treasury stock	(1)	(1)
Net cash provided by financing activities	4,447	17,183
Effect of exchange rate changes on cash, cash equivalents and restricted cash	(32)	(80)
Net decrease in cash, cash equivalents and restricted cash	(6,229)	4,934
Cash, cash equivalents and restricted cash, beginning of period	17,159	12,225
Cash, cash equivalents and restricted cash, end of period	10,930	17,159
Supplemental schedule of cash flows information:
Cash paid for interest		1
Supplemental disclosure of noncash operating activities:
Prepaid financing costs reported in accrued expenses	7
Supplemental disclosure of noncash investing activities:
Acquisition of computers, equipment and furniture through accounts payable		5
Supplemental disclosure of noncash financing activities:
Common stock issued for payment of commitment fee	$ 295	$ 295

Background and Liquidity

12 Months Ended

Apr. 30, 2020

Accounting Policies [Abstract]

Background and Liquidity

(1) Background and Liquidity

(a) Background

Ocean Power Technologies, Inc. (the “Company”) was founded in 1984 in New Jersey, commenced business operations in 1994 and re-incorporated in Delaware in 2007. We are a complete solutions provider, controlling the design, manufacturing, sales, installation, operations and maintenance of our products while working closely with partners that provide payloads, integration services, and marine installation capabilities. Our solutions provide distributed offshore power which is persistent, reliable, and economical along with power and communications for remote surface and subsea applications. Our mission and purpose is to utilize our proprietary, state-of-the-art technologies to reduce the global carbon footprint by providing renewable energy solutions for reliable electrical power and, in so doing, drive demand for our products and services, thus realizing positive stockholder returns. Since fiscal 2002, government agencies have accounted for a significant portion of the Company’s revenues. These revenues were largely for the support of product development efforts relating to our technology. Today our goal is to generate the majority of our revenue from the sale or lease of products and solutions, and sales of services to support our business operations. As we continue to develop and commercialize our products and services, we expect to have a net decrease in cash due to the use of cash from operating activities unless and until we achieve positive cash flow from the commercialization of solutions, products and services.

(b) Liquidity/Going Concern

Our consolidated financial statements have been prepared assuming the Company will continue as a going concern. The Company has experienced substantial and recurring losses from operations, which have contributed to an accumulated deficit of $220.1 million at April 30, 2020. At April 30, 2020, the Company had approximately $10.9 million in cash, cash equivalents and restricted cash on hand. On May 5, 2020 the Company received $0.9 million proceeds from the PPP Loan (see Note 17 to these Consolidated Financial Statements for more information). The Company generated revenues of only $1.7 million and $0.6 million during the years ended April 30, 2020 and 2019, respectively. Based on the Company’s cash, cash equivalents and restricted cash balances as of April 30, 2020 plus the subsequent proceeds from the PPP Loan, the Company believes that it will be able to finance its capital requirements and operations into the quarter ending April 30, 2021. The Company will require additional equity and/or debt financing to continue its operations. The Company cannot provide assurances that it will be able to secure additional funding when needed or at all, or, if secured, that such funding would be on favorable terms. These factors raise substantial doubt about the Company’s ability to continue as a going concern.

The consolidated financial statements have been prepared on a going concern basis, which contemplates the realization of assets and satisfaction of liabilities in the normal course of business. The consolidated financial statements do not include any adjustments relating to the recoverability and classification of recorded assets amounts or the amounts and classification of liabilities that might result from the outcome of this uncertainty.

Management is evaluating different strategies to obtain the required additional funding for future operations. These strategies may include, but are not limited to, continued pursuit of business opportunities; additional funding from current and /or new investors, officers and directors; borrowings of debt; a public offering of the Company’s equity or debt securities; partnerships and/or collaborations. There can be no assurance that any of these future-funding efforts will be successful.

In fiscal 2020 and 2019, the Company has continued to make investments in ongoing product development efforts in anticipation of future growth. The Company’s future results of operations involve significant risks and uncertainties. Factors that could affect the Company’s future operating results and cause actual results to vary materially from expectations include, but are not limited to, risks from lack of available financing and insufficient capital, the impact of COVID-19 on its business, performance of its products, its inability to market and commercialize its products and new products that it may develop, technology development, scalability of technology and production, dependence on skills of key personnel, concentration of customers and suppliers, deployment risks and laws, regulations and permitting. In order to continue to implement its business strategy, the Company requires additional equity and/or debt financing. The Company currently has committed sources of equity financing through its At the Market Offering Agreement with A.G.P/Alliance Global Partners (“AGP”) and the Aspire Capital financing (each discussed further below), but the Company cannot be sure that additional equity and/or debt financing will be available to the Company as needed on acceptable terms, or at all. Historically, the Company has raised capital through securities sales in the public capital markets. If sufficient additional financing is not obtained when needed, the Company may be required to further curtail or limit operations, product development costs, and/or selling, general and administrative activities in order to reduce its cash expenditures. This could cause the Company to be unable to execute its business plan, take advantage of future opportunities and may cause it to scale back, delay or eliminate some or all of its product development activities and/or reduce the scope of or cease its operations.

On August 13, 2018, the Company entered into a common stock purchase agreement with Aspire Capital Fund, LLC (“Aspire Capital”) which provided that, subject to certain terms, conditions and limitations, Aspire Capital was committed to purchase up to an aggregate of $10.0 million of shares of the Company’s common stock over a 30-month period that did not exceed 19.99% of the outstanding common stock on the date of the agreement. The number of shares the Company could issue within the 19.99% is 183,591 shares. Shareholder approval was not needed since the number of common stock offered for sale in the common stock purchase agreement did not exceed 19.99% of the outstanding common stock on the date of the agreement. In consideration for entering into the agreement, the Company issued to Aspire Capital 21,429 shares of our common stock as a commitment fee. The agreement was cancelled on October 24, 2019, and as of that date, the Company had sold 162,162 shares of common stock with an aggregate market value of $949,259 at an average price of $5.85 per share pursuant to this common stock purchase agreement.

On October 24, 2019, the Company entered into a new common stock purchase agreement with Aspire Capital which provides that, subject to certain terms, conditions and limitations, Aspire Capital is committed to purchase up to an aggregate of $10.0 million of shares of the Company’s common stock over a 30-month period that does not exceed 19.99% of the outstanding common stock on the date of the agreement. The number of shares the Company can issue within the 19.99% limit is 1,219,010 shares including shares issued as a commitment fee. At the 2019 annual meeting of stockholders, held on December 20, 2019, the Company’s stockholders approved an additional 5,400,000 shares to be issued pursuant to the common stock purchase agreement in excess of the 19.99% limit. In consideration for entering into the agreement, the Company issued to Aspire Capital 194,805 shares of our common stock as a commitment fee. As of April 30, 2020, the Company has sold 1,399,205 shares of common stock with an aggregate market value of approximately $1.1 million at an average price of $0.82 per share pursuant to this common stock purchase agreement.

On April 8, 2019, the Company sold 1,542,000 shares of common stock, which includes the sale of 642,000 shares of the Company’s common stock sold by the Company pursuant to the exercise, in full, of the over-allotment option by the underwriters in a public offering. As part of the public offering, the Company also sold prefunded warrants to purchase up to 3,385,680 shares of common stock and common warrants to purchase up to 4,927,680 shares of our common stock. The net proceeds to the Company from the offering were approximately $15.7 million, after deducting underwriter fees and offering expenses payable by the Company.

On January 7, 2019, the Company entered into an At the Market Offering Agreement (“2019 ATM Facility”) with A.G.P./Alliance Global Partners, under which the Company may issue and sell to or through AGP, acting as agent and/or principal, shares of the Company’s common stock having an aggregate offering price of up to $25 million. Through April 30, 2020, under the 2019 ATM Facility, the Company has issued 5,101,405 shares of its common stock with an aggregate market value of approximately $3.8 million at an average price of $0.74 per share and paid AGP a sales commission of $122,530 related to those shares.

The sale of additional equity or convertible securities could result in dilution to stockholders. If additional funds are raised through the issuance of debt securities, these securities could have rights senior to those associated with the Company’s common stock and could contain covenants that would restrict its operations. Financing may not be available in amounts or on terms acceptable to the Company, or at all. If the Company is unable to obtain required financing, it may be required to reduce the scope of its operations, including its planned product development and marketing efforts, which could materially and adversely harm its financial condition and operating results. If the Company is unable to secure additional financing, it may be forced to cease operations.

If our common stock is delisted from Nasdaq (see Note 15 – Commitments and Contingencies for more), our ability to raise capital through public offerings of our securities and to finance our operations could be adversely affected. See additional risk factors under “Part I, Item 1A – Risk Factors”. We also believe that delisting would likely result in decreased liquidity and/or increased volatility in our common stock and could harm our business and future prospects. In addition, we believe that, if our common stock is delisted, our stockholders would likely find it more difficult to obtain accurate quotations as to the price of the common stock and it may be more difficult for stockholders to buy or sell our common stock at competitive market prices, or at all.

Summary of Significant Accounting Policies

12 Months Ended

Apr. 30, 2020

Accounting Policies [Abstract]

Summary of Significant Accounting Policies

(2) Summary of Significant Accounting Policies

(a) Consolidation

The accompanying consolidated financial statements include the accounts of the Company and its majority-owned subsidiaries. All significant intercompany balances and transactions have been eliminated in consolidation.

(b) Use of Estimates

The preparation of the consolidated financial statements requires management of the Company to make a number of estimates and assumptions relating to the reported amounts of assets and liabilities and the disclosure of contingent assets and liabilities at the date of the consolidated financial statements and the reported amounts of revenues and expenses during the period. Significant items subject to such estimates and assumptions include estimated costs to complete projects and percentage of completion of customer contracts for purposes of revenue recognition. Actual results could differ from those estimates. The current economic environment, particularly the macroeconomic pressures in certain European countries, has increased the degree of uncertainty inherent in those estimates and assumptions.

(c) Revenue Recognition

A performance obligation is the unit of account for revenue recognition. The Company assesses the goods or services promised in a contract with a customer and identifies as a performance obligation either: a) a good or service (or a bundle of goods or services) that is distinct; or b) a series of distinct goods or services that are substantially the same and that have the same pattern of transfer to the customer. A contract may contain a single or multiple performance obligations. For contracts with multiple performance obligations, the Company allocates the contracted transaction price to each performance obligation based upon the relative standalone selling price, which represents the price the Company would sell a promised good or service separately to a customer. The Company determines the standalone selling price based upon the facts and circumstances of each obligated good or service. The majority of the Company’s contracts have no observable standalone selling price since the associated products and services are customized to customer specifications. As such, the standalone selling price generally reflects the Company’s forecast of the total cost to satisfy the performance obligation plus an appropriate profit margin.

The nature of the Company’s contracts may give rise to several types of variable considerations, including unpriced change orders and liquidated damages and penalties. Variable consideration can also arise from modifications to the scope of services. Variable consideration is included in the transaction price to the extent it is probable that a significant reversal of cumulative revenue recognized will not occur once the uncertainty associated with the variable consideration is resolved. Our estimates of variable consideration and determination of whether to include such amounts in the transaction price are based largely on our assessment of legal enforceability, performance and any other information (historical, current, and forecasted) that is reasonably available to us. ASU 2016-10 provides a practical expedient in ASC 606-10-25-18B that permits presentation of shipping and handling costs, that occur after control of the promised goods or services transfer to the customer, as fulfillment costs rather than evaluating whether the shipping and handling activities are promised services to the customer. The Company adopted this practical expedient.

The Company recognizes revenue when or as it satisfies a performance obligation by transferring a good or service to a customer, either (1) at a point in time or (2) over time. A good or service is transferred when or as the customer obtains control of it. The evaluation of whether control of each performance obligation is transferred at a point in time or over time is made at contract inception. Input measures such as costs incurred or time elapsed are utilized to assess progress against specific contractual performance obligations for the Company’s services. The selection of the method to measure progress towards completion requires judgment and is based on the nature of the services to be provided. For the Company, the input method using costs incurred or time elapsed best represents the measure of progress against the performance obligations incorporated within the contractual agreements. When the Company’s estimate of total costs to be incurred to satisfy the performance obligations exceed revenue, the Company recognizes the loss immediately.

The Company’s contracts are either cost plus or fixed price contracts. Under cost plus contracts, customers are billed for actual expenses incurred plus an agreed-upon fee. Under cost plus contracts, a profit or loss on a project is recognized depending on whether actual costs are more or less than the agreed upon amount.

The Company has two types of fixed price contracts, firm fixed price and cost-sharing. Under firm fixed price contracts, the Company receives an agreed-upon amount for providing products and services specified in the contract, a profit or loss is recognized depending on whether actual costs are more or less than the agreed upon amount. Under cost-sharing contracts, the fixed amount agreed upon with the customer is only intended to fund a portion of the costs on a specific project. Under cost sharing contracts, an amount corresponding to the revenue is recorded in cost of revenues, resulting in gross profit on these contracts of zero. The Company’s share of the costs is recorded as product development expense. The Company reports its disaggregation of revenue by contract type since this method best represents the Company’s business. For the twelve-month periods ended April 30, 2020 and 2019, all of the Company’s contracts were classified as firm fixed price.

As of April 30, 2020, the Company’s total remaining performance obligations, also referred to as backlog, totaled $1.0 million. The Company expects to recognize approximately 79%, or $0.8 million, of the remaining performance obligations as revenue over the next twelve months.

The Company also enters into lease arrangements for its PB3 with certain customers. As of April 30, 2020, the Company has one lease arrangement with 18 months remaining on its term. Revenue related to multiple-element arrangements is allocated to lease and non-lease elements based on their relative standalone selling prices or expected cost plus a margin approach. Lease elements generally include a PB3 and components, while non-lease elements generally include engineering, monitoring and support services. In the lease arrangement, the customer is provided an option to extend the lease term or purchase the leased PB3 at some point during and/or at the end of the lease term.

The Company classifies leases as either operating or financing in accordance with the authoritative accounting guidance contained within ASC Topic 842, “Leases”. At inception of the contract, the Company evaluates the lease against the lease classification criteria within ASC Topic 842. If the direct financing or sales-type classification criteria are met, then the lease is accounted for as a finance lease. All others are treated as an operating lease.

The Company recognizes revenue from operating lease arrangements generally on a straight-line basis over the lease term and is presented in Revenues in the Consolidated Statement of Operations. The lease income for the twelve months ended April 30, 2020 and 2019 was immaterial.

(d) Cash and Cash Equivalents, Restricted Cash and Security Agreements

Cash and Cash Equivalents

The Company considers all highly liquid investments with a maturity of three months or less when purchased to be cash equivalents. The Company invests excess cash in a money market account. The following table summarizes cash and cash equivalents for the years ended April 30, 2020 and 2019:

	April 30, 2020		April 30, 2019
	(in thousands)

Checking and savings accounts	$	1,551	$	860
Money market account		8,451		15,800
	$	10,002	$	16,660

Restricted Cash and Security Agreements

A portion of the Company’s cash is restricted under the terms of various security agreements.

One agreement is between the Company and Barclays Bank. Under this agreement, the cash is on deposit at Barclays Bank and serves as security for letters of credit and bank guarantees that are expected to be issued by Barclays Bank on behalf of OPT LTD, one of the Company’s subsidiaries, under a credit facility established by Barclays Bank for OPT LTD. The credit facility is approximately €0.3 million ($0.4 million) and carries a fee of 1% per annum of the amount of any such obligations issued by Barclays Bank. The credit facility does not have an expiration date but is cancelable at the discretion of the bank. As of April 30, 2020, there were no letters of credit outstanding under this agreement.

The other agreements are between the Company and Santander Bank. Cash is on deposit at Santander Bank and serves as security for a letter of credit issued by Santander Bank for the lease of warehouse/office space in Monroe Township, New Jersey. This agreement cannot be extended beyond January 31, 2025 and is cancelable at the discretion of the bank. Santander Bank also issued two letters of credit to subsidiaries of EGP pursuant to the Company’s contracts with EGP. The first letter of credit was issued in the amount of $125,690 that expires in February 2021. The second letter of credit was issued in the amount of $645,467. This second letter of credit will be reduced to $322,734 after achieving certain milestones and to $64,547 after certain additional milestones are achieved. The remaining amount expires in September 2021. The following table summarizes restricted cash for the years ended April 30, 2020 and 2019:

	April 30, 2020		April 30, 2019
	(in thousands)

Barclay’s Bank Agreement	$	-	$	344
Santander Bank		928		155
	$	928	$	499

The following table provides a reconciliation of cash, cash equivalents and restricted cash reported within the Statement of Financial Position that sum to the total of the same such amounts shown in the Statement of Cash Flows for the years ended April 30, 2020 and 2019:

	April 30, 2020		April 30, 2019
	(in thousands)

Cash and cash equivalents	$	10,002	$	16,660
Restricted cash- short term		707		344
Restricted cash- long term		221		155
	$	10,930	$	17,159

(e) Property and Equipment

Property and equipment is stated at cost, less accumulated depreciation and amortization. Depreciation and amortization is calculated using the straight-line method over the estimated useful lives (three to seven years) of the assets. Leasehold improvements are amortized using the straight-line method over the shorter of the estimated useful life of the asset or the remaining lease term. Expenses for maintenance and repairs are charged to operations as incurred. Property and equipment is also reviewed for impairment whenever events or changes in circumstances indicate that the carrying amount of the asset may not be recoverable. Recoverability of assets to be held and used is measured by a comparison of the carrying amount of the asset to estimated undiscounted future cash flows expected to be generated by the asset. If the carrying amount of the asset exceeds its estimated future cash flows, then an impairment charge is recognized in the amount by which the carrying amount of the asset exceeds the fair value of the asset.

Description		Estimated useful life

Equipment		5 - 7 years
Computer equipment & software		3 years
Office furniture & fixtures		3 - 7 years
Equipment under capitalized lease		Over the life of the lease
Leasehold improvements		Shorter of the estimated useful life or lease term

(f) Foreign Exchange Gains and Losses

The Company maintains cash accounts that are denominated in British pound sterling, Euros and Australian dollars. These amounts are included in cash, cash equivalents and restricted cash on the accompanying Consolidated Balance Sheets. Such positions may result in realized and unrealized foreign exchange gains or losses from exchange rate fluctuations, which are included in “Foreign exchange gain/(loss)” in the accompanying Consolidated Statements of Operations.

(g) Concentration of Credit Risk

Financial instruments that potentially subject the Company to credit risk consist principally of trade accounts receivable and cash. The Company believes that its credit risk is limited because the Company’s current contracts are with companies with a reliable payment history. The Company invests its excess cash in a money market fund and does not believe that it is exposed to any significant risks related to its cash accounts and money market fund. Cash is also maintained at foreign financial institutions. Cash in foreign financial institutions as of April 30, 2020 was $0.3 million.

The table below shows the percentage of the Company’s revenues derived from customers whose revenues accounted for at least 10% of the Company’s consolidated revenues for at least one of the periods indicated:

	Twelve months ended April 30,
	2020			2019

Eni S.p.A.		10	%		54	%
Premier Oil UK Limited		9	%		33	%
EGP		72	%		4	%
Other		9	%		9	%
		100	%		100	%

The loss of, or a significant reduction in revenues from a current customer could significantly impact the Company’s financial position or results of operations. The Company does not require its customers to maintain collateral.

(h) Warrant Accounting

The Company accounts for warrants issued in connection with its public offerings in accordance with the guidance on “Accounting for Certain Financial Instruments with Characteristics of Both Liabilities and Equity” in Topic 480 which provides that warrants meeting the classification of a liability award are recorded as a liability at its fair value. The warrant liabilities are subject to re-measurement at each balance sheet date using the Black-Scholes option pricing model. The Company recognizes any change in fair value in its consolidated statements of operations within “Gain due to the change in fair value of warrant liabilities”. The Company will continue to adjust the carrying value of the warrants for changes in the estimated fair value until such time as these instruments are exercised or expire. At that time, the liabilities will be reclassified to “Additional paid-in capital”, a component of “Stockholders’ equity” on the Consolidated Balance Sheets. The warrants issued in connection with the Company’s public offerings in June and July 2016 met the criteria of a liability award and were classified in warrant liabilities. The pre-funded and common warrants issued in the Company’s April 8, 2019 public offering did not meet the criteria to be classified as a liability award and therefore were treated as an equity award.

(i) Net Loss per Common Share

Basic and diluted net loss per share for all periods presented is computed by dividing net loss by the weighted average number of shares of common stock and common stock equivalents outstanding during the period. The pre-funded warrants were determined to be common stock equivalents and have been included in the weighted average number of shares outstanding for calculation of the basic earnings per share number. Due to the Company’s net losses, potentially dilutive securities, consisting of options to purchase shares of common stock, warrants on common stock and unvested restricted stock issued to employees and non-employee directors, were excluded from the diluted loss per share calculation due to their anti-dilutive effect.

In computing diluted net loss per share on the Consolidated Statement of Operations, warrants on common stock, options to purchase shares of common stock and unvested restricted stock issued to employees and non-employee directors, totaling 5,564,438 and 5,013,981 for the years ended April 30, 2020 and 2019, respectively, were excluded from each of the computations as the effect would be anti-dilutive due to the Company’s losses.

(j) Share-Based Compensation

Costs resulting from all share-based payment transactions are recognized in the consolidated financial statements at their fair values. The aggregate share-based compensation expense recorded in the consolidated statements of operations for the years ended April 30, 2020 and 2019 was approximately $0.3 million in each of these years. The following table summarizes share-based compensation related to the Company’s share-based plans by expense category for the years ended April 30, 2020 and 2019:

	Twelve months ended April 30,
	2020		2019


Product development	$	89	$	29
Selling, general and administrative		251		266
Total share-based compensation expense	$	340	$	295

(k) Deferred Rent

On March 31, 2017, the Company signed a 7-year lease for approximately 56,000 square feet in Monroe Township, New Jersey that is being used as warehouse/production space, as well as the Company’s principal offices and corporate headquarters. The lease was classified as an operating lease. Rent payments relating to the Monroe premises are subject to annual increases. The minimum monthly payments will vary over the 7-year term of the lease. The Landlord has provided the Company a tenant improvement allowance in an amount up to, but not exceeding, $137,563 to be applied to the cost of tenant improvement work. The Company recorded lease incentive liability to deferred rent. With the Company’s adoption of Accounting Standards Update (“ASU”) No. 2016-02 on May 1, 2019, the balances in lease incentive liability and deferred rent have been included in the value of the right of use asset.

(l) Income Taxes

Income taxes are accounted for under the asset and liability method. Deferred tax assets and liabilities are recognized for the future tax consequences attributable to differences between the financial statement carrying amounts of existing assets and liabilities and their respective tax bases and operating loss and tax credit carry forwards. Deferred tax assets and liabilities are measured using enacted tax rates expected to apply to taxable income in the years in which those temporary differences and operating loss and tax credit carry forwards are expected to be recovered, settled or utilized. The effect on deferred tax assets and liabilities of a change in tax rates is recognized in income in the period that includes the enactment date.

The Company recognizes the effect of income tax positions only if those positions are more likely than not of being sustained upon examination. Recognized income tax positions are measured at the largest amount that is greater than 50% likely of being realized. Changes in recognition or measurement are reflected in the period in which the change in judgment occurs. The Company records interest related to unrecognized tax benefits in interest expense and penalties in selling, general, and administrative expenses, to the extent incurred.

(m) Accumulated Other Comprehensive Loss

The functional currency for the Company’s foreign operations is the applicable local currency. The translation from the applicable foreign currencies to U.S. dollars is performed for balance sheet accounts using the exchange rates in effect at the balance sheet date and for revenue and expense accounts using an average exchange rate during the period. The unrealized gains or losses resulting from such translation are included in accumulated other comprehensive loss within stockholders’ equity.

(n) Recently Issued Accounting Standards

In February 2016, the Financial Accounting Standards Board (“FASB”) issued ASU No. 2016-02, “Leases (Topic 842).” which amends the existing guidance on accounting for leases. Topic 842 was further clarified and amended within ASU 2017-13, ASU 2018-01, ASU 2018-10, ASU 2018-11 and ASU 2018-20. The new standard establishes a right-of-use (ROU) model that requires a lessee to record a ROU asset and a lease liability on the balance sheet for all leases with terms longer than twelve months or leases that contain a purchase option that is reasonably certain to be exercised. Leases will be classified as either finance or operating, with classification affecting the pattern of expense recognition in the income statement. ASU 2016-02 was effective for annual periods beginning after December 15, 2018, including interim periods within those annual periods, with early adoption permitted. The guidance permits the Company to utilize the package of practical expedients that, upon adoption of Topic 842, allows entities to (1) not reassess whether any expired or existing contracts are or contain leases, (2) retain the classification of leases (e.g., operating or finance lease) existing as of the date of adoption and (3) not reassess initial direct costs for any existing leases. Additionally, the Company elected to exclude short-term leases having initial terms of 12 months or less and recognizes rent expense on a straight-line basis over the lease term. The Company adopted Topic 842 on May 1, 2019 using the modified retrospective approach. Under this approach, comparative periods presented in the financial statements in which the new lease standard is adopted will continue to be presented in accordance with prior GAAP. The adoption of this standard resulted in the Company recognizing a ROU asset and a lease liability of approximately $1.4 million and $1.5 million, respectively, and eliminating deferred rent of $39,000 and an unamortized lease incentive receivable of $108,000. Refer to Note 6 to the Consolidated Financial Statements for disclosure requirements related to the adoption of this standard.

In June 2016, the FASB issued ASU No. 2016-13, “Financial Instruments - Credit Losses (Topic 326), Measurement of Credit Losses on Financial Instruments.” The amendment in this update replaces the incurred loss impairment methodology in current GAAP with a methodology that reflects expected credit losses on instruments within its scope, including trade receivables. This update is intended to provide financial statement users with more decision-useful information about the expected credit losses. This ASU is effective for annual periods and interim periods beginning after December 15, 2019. The Company is currently evaluating the impact the adoption of ASU 2016-13 will have on its consolidated financial statements.

In August 2018, the FASB issued ASU No. 2018-13, “Fair Value Measurement (Topic 820).” The ASU modifies, removes, and adds several disclosure requirements on fair value measurements in Topic 820, Fair Value Measurement. ASU 2018-13 is effective for all entities for fiscal years, and interim periods within those fiscal years, beginning after December 15, 2019. The amendments on changes in unrealized gains and losses, the range and weighted average of significant unobservable inputs used to develop Level 3 fair value measurements, and the narrative description of measurement uncertainty should be applied prospectively for only the most recent interim or annual period presented in the initial fiscal year of adoption. All other amendments should be applied retrospectively to all periods presented upon their effective date. Early adoption is permitted upon issuance of ASU 2018-13. An entity is permitted to early adopt any removed or modified disclosures upon issuance of ASU 2018-13 and delay adoption of the additional disclosures until their effective date. The Company is evaluating the effect ASU 2018-13 will have on its Consolidated Financial Statements and disclosures and has not yet determined the effect of the standard on its ongoing financial reporting at this time.

In August 2018, the FASB issued ASU No. 2018-15, “Intangibles — Goodwill and Other — Internal-Use Software (Subtopic 350-40).” The ASU provides for the recognition of an intangible asset for the costs of internal-use software licenses included in a cloud computing arrangement. Costs of arrangements that do not include a software license should be accounted for as a service contract and expensed as incurred. This ASU is effective for fiscal years beginning after December 15, 2019, with early adoption permitted. The ASU permits two methods of adoption: prospectively to all implementation costs incurred after the date of adoption, or retrospectively to each prior reporting period presented. The Company is evaluating the effect ASU 2018-15 will have on its Consolidated Financial Statements and disclosures and has not yet determined the effect of the standard on its ongoing financial reporting at this time.

Account Receivable, Contract Assets, and Contract Liabilities

12 Months Ended

Apr. 30, 2020

Account Receivable Contract Assets And Contract Liabilities

Account Receivable, Contract Assets, and Contract Liabilities

(3) Account Receivable, Contract Assets, and Contract Liabilities

The following provides further details on the balance sheet accounts of accounts receivable, contract assets, and contract liabilities.

Accounts Receivable

The Company grants credit to its customers, generally without collateral, under normal payment terms (typically 30 to 60 days after invoicing). Generally, invoicing occurs after the related services are performed or control of good has transferred to the customer. Accounts receivable represents an unconditional right to consideration arising from the Company’s performance under contracts with customers. The carrying value of such receivables represent their estimated realizable value. Accounts receivable consisted of the following at April 30, 2020 and 2019.

	April 30, 2020			April 30, 2019
	(in thousands)

Opening balance	$	63		$	171
Amount invoiced to customers		1,386			857
Collections		(1,344	)		(965	)
Ending balance	$	105		$	63

Contract Assets and Contract Liabilities

Contract assets include unbilled amounts typically resulting from arrangements whereby the right to payment is conditioned on completing additional tasks or services for a performance obligation. The increase in contract assets is primarily a result of services performed for EGP but unbilled during the twelve months ended April 30, 2020.

Contract liabilities consist of amounts invoiced to customers in excess of revenue recognized. The decrease in contract liabilities is primarily a result of recognizing more revenue during the twelve months ended April 30, 2020.

Other Current Assets

12 Months Ended

Apr. 30, 2020

Deferred Costs, Capitalized, Prepaid, and Other Assets Disclosure [Abstract]

Other Current Assets

(4) Other Current Assets

Other current assets consist of the following at April 30, 2020 and 2019:

	April 30, 2020		April 30, 2019
	(in thousands)

Deposits	$	60	$	63
Other receivables		2		44
Prepaid insurance		124		93
Prepaid offering costs		275		144
Prepaid expenses- other		127		193
	$	588	$	537

Property and Equipment

12 Months Ended

Apr. 30, 2020

Property, Plant and Equipment [Abstract]

Property and Equipment

(5) Property and Equipment

The components of property and equipment as of April 30, 2020 and 2019 consisted of the following:

	April 30, 2020			April 30, 2019
	(in thousands)

Equipment	$	342			339
Computer equipment & software		486			558
Office furniture & equipment		339			341
Leasehold improvements		474			474
Equipment under capitalized lease		-			103
Construction in process		15			15
	$	1,656		$	1,830
Less: accumulated depreciation		(1,157	)		(1,238	)
	$	499		$	592

Depreciation expense was approximately $0.2 million and $0.2 million for the years ended April 30, 2020 and 2019, respectively.

Leases

12 Months Ended

Apr. 30, 2020

Leases [Abstract]

Leases

(6) Leases

Lessor Information

As of April 30, 2020, the Company has one lease which has been classified as an operating lease per accounting guidance contained within ASC Topic 842, “Leases”. The Company’s remaining operating lease term on this lease is 18 months. The maturity of lease payments remaining on this lease is immaterial. The accounting of the operating lease income according to ASC Topic 842, “Leases” is similar to the accounting in prior years.

Lessee Information

The Company has one lease for its facility located in Monroe Township, New Jersey that is used as warehouse/production space and the Company’s principal offices and corporate headquarters. The initial lease term is for 7 years with an option to extend the lease for another 5 years. The lease is classified as an operating lease. The operating lease is included in right-of-use assets, lease liabilities- current and lease liabilities- long-term on the Company’s Consolidated Balance Sheets. The Company has elected the package of practical expedients which applies to leases that commenced before the adoption date. By electing the package of practical expedients, the Company did not need to reassess whether any existing contracts are or contain leases, the lease classification for any existing leases and initial direct costs for any existing leases.

Right-of-use asset and operating lease liabilities are recognized based on the present value of future minimum lease payments over the lease term at the commencement date. When the implicit rate of the lease is not provided or cannot be determined, the Company used the incremental borrowing rate based on the information available at the effective date to determine the present value of future payments. Lease terms may include options to extend or terminate the lease when it is reasonably certain that the Company will exercise those options. The renewal options have not been included in the lease term as they are not reasonably certain of exercise. Lease expense for minimum lease payments is recognized on a straight- line basis over the lease term and consists of interest on the lease liability and the amortization of the right of use asset. Variable lease expenses, if any, are recorded as incurred. The operating lease expense in the Consolidated Statement of Operations for the twelve months ended April 30, 2020 was $317,000. The operating cash flows from operating leases cash payments for the twelve months ended April 30, 2020 was $322,000.

Information related to the Company’s right-of use assets and lease liabilities as of April 30, 2020 is as follows:

	April 30, 2020
		(in thousands)

Operating lease:
Operating right-of-use asset, net	$	1,165

Right-of-use liability- current		229
Right-of-use liability- long term		1,078
Total lease liability	$	1,307

Weighted average remaining lease term- operating leases		4.49 years
Weighted average discount rate- operating leases		8.5	%

Total remaining lease payments under the Company’s operating leases are as follows:

	April 30, 2020
		(in thousands)

2021		331
2022		341
2023		352
2024		362
Thereafter		184
Total future minimum lease payments	$	1,570
Less imputed interest		(263	)
Total	$	1,307

ASC 840 Disclosure

The Company elected the modified retrospective transition method and is required to present previously disclosed information under the prior accounting standard for leases.

Lessee Information

Future minimum lease payments under the Company’s operating lease as of April 30, 2019 were as follows:

	April 30, 2019
		(in thousands)

2020		322
2021		331
2022		341
2023		352
2024		362
Thereafter		184
	$	1,892

Accrued Expenses

12 Months Ended

Apr. 30, 2020

Payables and Accruals [Abstract]

Accrued Expenses

(7) Accrued Expenses

Accrued expenses consisted of the following at April 30, 2020 and 2019:

	April 30, 2020		April 30, 2019
	(in thousands)

Project costs	$	48	$	9
Contract loss reserve		216		211
Employee incentive payments		-		580
Accrued salary and benefits		483		500
Legal and accounting fees		283		273
Accrued taxes payable		177		177
Other		146		188
	$	1,353	$	1,938

Warrants

12 Months Ended

Apr. 30, 2020

Warrants and Rights Note Disclosure [Abstract]

Warrants

(8) Warrants

Liability Classified Warrants

On June 2, 2016, the Company entered into a securities purchase agreement, which was amended on June 7, 2016 (as amended, the “June Purchase Agreement”) with certain institutional purchasers (the “June Purchasers”). Pursuant to the terms of the June Purchase Agreement, the Company sold an aggregate of 20,850 shares of common stock together with warrants to purchase up to an aggregate of 7,298 shares of common stock. Each share of common stock was sold together with a warrant to purchase 0.35 of a share of common stock at a combined purchase price of $92.00. The warrants have an exercise price of $121.60 per share, became exercisable on December 3, 2016 (“Initial Exercise Date”), and will expire five years following the Initial Exercise Date. As of April 30, 2020, none of the warrants have been exercised.

On July 22, 2016, the Company entered into a Second Amendment to the Purchase Agreement (the “Second Amended Purchase Agreement”) with certain institutional purchasers (the “July Purchasers”). Pursuant to the terms of the Second Amended Purchase Agreement, the Company sold an aggregate of 29,750 shares of common stock together with warrants to purchase up to an aggregate of 8,925 shares of common stock. Each share of common stock was sold together with a warrant to purchase 0.30 of a share of common stock at a combined purchase price of $135.00. The Warrants were exercisable immediately at an exercise price of $187.20 per share. The warrants will expire on the fifth (5th) anniversary of the initial date of issuance. As of April 30, 2020, none of the warrants have been exercised.

Equity Classified Warrants

On April 8, 2019, the Company issued and sold 1,542,000 shares of common stock and pre-funded warrants to purchase up to 3,385,680 shares of common stock and common warrants to purchase up to 4,927,680 shares of our common stock in an underwritten public offering. The public offering price for the pre-funded warrants was equal to the public offering price of the common stock, less the $0.01 per share exercise price of each warrant. The pre-funded warrants have no expiration date. As of April 30, 2020, all of the pre-funded warrants have been exercised. The common stock warrants have an exercise price of $3.85 per share and expire five years from the issuance date. As of April 30, 2020, none of the common stock warrants have been exercised.

The Company accounts for warrants issued in connection with its June and July 2016 public offerings in accordance with the guidance on “Accounting for Certain Financial Instruments with Characteristics of Both Liabilities and Equity” in Topic 480 which provides that the Company classify the warrant instruments as a liability at its fair value. The warrant liabilities are subject to re-measurement at each balance sheet date using the Black-Scholes option pricing model. The June and July 2016 warrants contain a feature whereby they could require the transfer of assets and therefore are classified as a liability award in accordance with the guidance in Topic 480. The warrants have a value of zero at April 30, 2020 and $6,000 at April 30, 2019 and are reflected within “Warrant liabilities” in the Consolidated Balance Sheets. The pre-funded and common warrants issued in the Company’s April 8, 2019 public offering did not meet the criteria to be classified as a liability award and therefore were treated as an equity award and recorded as a component of stockholders’ equity in the Consolidated Balance Sheets.

An unrealized gain of $6,000 and $0.2 million, were included within “Gain due to change in fair value of warrant liabilities” in the Consolidated Statements of Operations for the year ended April 30, 2020 and 2019, respectively. The Company determined the fair value using the Black-Scholes option pricing model with the following assumptions for the period ended April 30, 2020 and 2019:

	April 30, 2020			April 30, 2019

Dividend rate		0.0	%		0.0	%
Risk-free rate		0.17% - 0.19	%		2.2% - 2.3	%
Expected life (years)		1.2 - 1.6			2.2 - 2.6
Expected volatility		81.8% - 112.7	%		110.0% - 153.4	%

Preferred Stock

12 Months Ended

Apr. 30, 2020

Equity [Abstract]

Preferred Stock

(9) Preferred Stock

The Company has authorized 5,000,000 shares of undesignated preferred stock with a par value of $0.001 per share. As of April 30, 2020, and 2019, no shares of preferred stock had been issued.

Common Stock

12 Months Ended

Apr. 30, 2020

Equity [Abstract]

Common Stock

(10) Common Stock

As of April 30, 2020, the Company has 100,000,000 shares authorized with a par value of $0.001 per share and 12,939,420 shares issued.

On August 13, 2018, the Company entered into a common stock purchase agreement with Aspire Capital which provided that, subject to certain terms, conditions and limitations, Aspire Capital was committed to purchase up to an aggregate of $10.0 million of shares of the Company’s common stock over a 30-month period that did not exceed 19.99% of the outstanding common stock on the date of the agreement. The number of shares the Company could issue within the 19.99% was 183,591 shares. Shareholder approval was not needed since the number of common stock offered for sale in the common stock purchase agreement did not exceed 19.99% of the outstanding common stock on the date of the agreement. In consideration for entering into the agreement, the Company issued to Aspire Capital 21,429 shares of common stock as a commitment fee. The agreement was cancelled on October 24, 2019, and as of that date, the Company had sold 162,162 shares of common stock with an aggregate market value of $949,259 at an average price of $5.85 per share pursuant to this common stock purchase agreement.

On October 24, 2019, the Company entered into a new common stock purchase agreement with Aspire Capital which provides that, subject to certain terms, conditions and limitations, Aspire Capital is committed to purchase up to an aggregate of $10.0 million of shares of the Company’s common stock over a 30-month period that does not exceed 19.99% of the outstanding common stock on the date of the agreement. The number of shares the Company can issue within the 19.99% limit is 1,219,010 shares. At the 2019 annual meeting of stockholders, held on December 20, 2019, the Company’s stockholders approved an additional 5,400,000 shares to be issued pursuant to the common stock purchase agreement in excess of the 19.99% limit. In consideration for entering into the agreement, the Company issued to Aspire Capital 194,805 shares of common stock as a commitment fee. As of April 30, 2020, the Company has sold 1,399,205 shares of common stock with an aggregate market value of approximately $1.1 million at an average price of $0.82 per share pursuant to this common stock purchase agreement.

On January 7, 2019, the Company entered into the 2019 ATM Facility with A.G.P/Alliance Global Partners, under which the Company may issue and sell to or through A.G.P., acting as agent and/or principal, shares of the Company’s common stock having an aggregate offering price of up to $25 million. As of April 30, 2020, under the 2019 ATM Facility the Company has issued 5,101,405 shares of its common stock with an aggregate market value of approximately $3.8 million at an average price of $0.74 per share and paid AGP a sales commission of approximately $122,530 related to those shares.

On April 8, 2019, the Company sold 1,542,000 shares of common stock, which includes the sale of 642,000 shares of the Company’s common stock sold by the Company pursuant to the exercise, in full, of the over-allotment option by the underwriters in a public offering, prefunded warrants to purchase up to 3,385,680 shares of common stock and common warrants to purchase up to 4,927,680 shares of common stock in an underwritten public offering. The net proceeds to the Company from the offering were approximately $15.7 million, after deducting underwriter’s fees and offering expenses payable by the Company.

Treasury Shares

12 Months Ended

Apr. 30, 2020

Equity [Abstract]

Treasury Shares

(11) Treasury Shares

During the years ended April 30, 2020 and 2019, 481 and 89 shares of Common Stock, respectively, were purchased by the Company from employees to pay taxes related to the vesting of restricted stock.

Share-Based Compensation Plans

12 Months Ended

Apr. 30, 2020

Share-based Payment Arrangement [Abstract]

Share-Based Compensation Plans

(12) Share-Based Compensation Plans

In 2015, upon approval by the Company’s stockholders, the Company’s 2015 Omnibus Incentive Plan (the “2015 Plan”) became effective. A total of 12,036 shares were authorized for issuance under the 2015 Omnibus Incentive Plan, including shares available for awards under the 2006 Stock Incentive Plan remaining at the time that plan terminated, or that were subject to awards under the 2006 Stock Incentive Plan that thereafter terminated by reason of expiration, forfeiture, cancellation or otherwise. On October 21, 2016 upon approval by the Company’s stockholders the Company increased the number of shares authorized for issuance to 32,036. On December 7, 2018, upon approval by the Company’s stockholders, the Company increased the number of shares authorized for issuance to 132,036. On December 20, 2019, upon approval by the Company’s stockholders, the Company increased the number of shares authorized for issuance to 732,036. If any award under the 2006 Stock Incentive Plan or 2015 Plan expires, is cancelled, terminates unexercised or is forfeited, those shares become again available for grant under the 2015 Plan. The 2015 Plan will terminate ten years after its effective date, in October 2025, but is subject to earlier termination as provided in the 2015 Plan. As of April 30, 2020, the Company has 168,808 shares available for future issuance under the 2015 Plan.

On January 18, 2018, the Company’s Board of Directors adopted the Company’s Employment Inducement Incentive Award Plan (the “2018 Inducement Plan”) pursuant to which the Company reserved 25,000 shares of common stock for issuance under the Inducement Plan. In accordance with Rule 5635(c)(4) and Rule 5635(c)(3) of the Nasdaq Listing Rules, awards under the Inducement Plan may only be made to individuals not previously employees of the Company (or following such individuals’ bona fide period of non-employment with the Company), as an inducement material to the individuals’ entry into employment with the Company. An award is any right to receive the Company’s common stock pursuant to the 2018 Inducement Plan, consisting of a performance share award, restricted stock award, a restricted stock unit award or a stock payment award. As of April 30, 2020, there were 11,487 shares available for grant under the 2018 Inducement Plan.

Stock Options

The Company estimates the fair value of each stock option award granted with service-based vesting requirements, using the Black-Scholes option pricing model, assuming no dividends, and using the weighted average valuation assumptions noted in the following table. The risk-free rate is based on the US Treasury yield curve in effect at the time of grant. The expected life (estimated period of time outstanding) of the stock options granted was estimated using the “simplified” method as permitted by the SEC’s Staff Accounting Bulletin No. 110, Share-Based Payment. Expected volatility was based on the Company’s historical volatility over the expected life of the stock option granted. There were 411,666 and 49,750 shares granted for the periods ended April 30, 2020 and 2019, respectively.

	Twelve months ended April 30,
	2020			2019

Risk-free interest rate		1.7	%		2.7	%
Expected dividend yield		0.0	%		0.0	%
Expected life (in years)		5.5- 5.7			5.5
Expected volatility		127.6% - 128.2	%		126.4	%

The above assumptions were used to determine the weighted average per share fair value of $0.92 and $7.15 for stock options granted during the years ended April 30, 2020 and 2019, respectively.

Performance Stock Options

In January of 2020, the Company issued 81,334 performance-based stock options to two of its executives. The awards vest over 2 years if there is positive total shareholder return (e.g. share price increase) as measured to the 5-day (January 11-15, 2021) and (January 10-14, 2022) share price volume weighted average price (“VWAP”). There were 81,334 shares unvested and outstanding for the year ended April 30, 2020. The Company determined these awards contain a market- based condition and estimated the fair value using the Monte Carlo simulation model with the following assumptions:

Risk-free interest rate	2.3	%
Expected dividend yield	0.0	%
Expected life (in years)	10.0
Expected volatility	115.0	%

The above assumptions were used to determine the weighted average per share fair value of $0.82 for stock options granted during the year ended April 30, 2020.

A summary of stock options under our stock incentive plans is detailed in the following table.

						Weighted
						Average
				Weighted		Remaining
	Shares			Average		Contractual
	Underlying			Exercise		Term
	Options			Price		(In Years)
Outstanding as of April 30, 2019		65,572		$	21.08		8.9
Granted		493,000		$	1.05
Exercised		-		$	-
Cancelled/forfeited		(3,097	)	$	44.32
Outstanding as of April 30, 2020		555,475		$	3.19		9.5
Exercisable as of April 30, 2020		62,475		$	20.09		7.9

As of April 30, 2020, the total intrinsic value of both outstanding and exercisable options was zero. As of April 30, 2020, approximately 493,000 options were unvested, which had no intrinsic value and a weighted average remaining contractual term of 9.7 years. There was approximately $0.3 million and $0.2 million of total recognized compensation cost related to stock options during each of the years ended April 30, 2020 and 2019, respectively. As of April 30, 2020, there was approximately $0.3 million of total unrecognized compensation cost related to unvested stock options granted under the plans. This cost is expected to be recognized over a weighted-average period of 1.0 years. The Company typically issues newly authorized but unissued shares to satisfy option exercises under these plans.

Restricted Stock

Compensation expense for unvested restricted stock is generally recorded based on its market value on the date of grant and recognized ratably over the associated service and performance period. During the year ended April 30, 2020, the Company granted 13,513 shares subject to service-based vesting requirements.

A summary of unvested restricted stock under our stock incentive plans is as follows:

				Weighted
	Number			Average Price per
	of Shares			Share

Issued and unvested at April 30, 2019		4,506		$	30.08
Granted		13,513		$	1.48
Vested		(4,380	)	$	30.14
Cancelled/forfeited		(126	)	$	28.00
Issued and unvested at April 30, 2020		13,513		$	1.48

There was approximately $15,000 and $0.1 million of total recognized compensation cost related to restricted stock for the years ended April 30, 2020 and 2019, respectively. As of April 30, 2020, there is $10,000 of unrecognized compensation cost remaining related to unvested restricted stock granted under our plans. This cost is expected to be recognized over a weighted-average period of 0.6 years.

During the year ended April 30, 2020, the Company granted 51,547 shares, subject to service-based vesting requirements, to an employee that were granted outside the Company stock incentive plans. There was approximately $20,000 of total recognized compensation cost, and $30,000 of unrecognized compensation cost, related to this award for the year ended April 30, 2020. This unrecognized cost is expected to be recognized over a weighted-average period of 0.6 years.

Fair Value Measurements

12 Months Ended

Apr. 30, 2020

Fair Value Disclosures [Abstract]

Fair Value Measurements

(13) Fair Value Measurements

The Company measures and reports certain financial and non-financial assets and liabilities on a fair value basis. Fair value is the price that would be received to sell an asset or paid to transfer a liability in an orderly transaction between market participants at the measurement date (exit price). GAAP specifies a three-level hierarchy that is used when measuring and disclosing fair value. The fair value hierarchy gives the highest priority to quoted prices available in active markets (i.e., observable inputs) and the lowest priority to data lacking transparency (i.e., unobservable inputs). An instrument’s categorization within the fair value hierarchy is based on the lowest level of significant input to its valuation. The following is a description of the three hierarchy levels.

Level 1		Unadjusted quoted prices in active markets that are accessible at the measurement date for identical, unrestricted assets or liabilities. Active markets are considered to be those in which transactions for the assets or liabilities occur in sufficient frequency and volume to provide pricing information on an ongoing basis.

Level 2		Quoted prices in markets that are not active, or inputs which are observable, either directly or indirectly, for substantially the full term of the asset or liability. This category includes quoted prices for similar assets or liabilities in active markets and quoted prices for identical or similar assets or liabilities in inactive markets.

Level 3		Unobservable inputs are not corroborated by market data. This category is comprised of financial and non-financial assets and liabilities whose fair value is estimated based on internally developed models or methodologies using significant inputs that are generally less readily observable from objective sources.

Transfers into or out of any hierarchy level are recognized at the end of the reporting period in which the transfers occurred. There were no transfers between any levels during the year ended April 30, 2020 and 2018.

The following information is provided to help readers gain an understanding of the relationship between amounts reported in the accompanying consolidated financial statements and the related market or fair value. The disclosures include financial instruments and derivative financial instruments, other than investment in affiliates.

Following are descriptions of the valuation methodologies used to measure material assets and liabilities at fair value and details of the valuation models, key inputs to those models and significant assumptions utilized.

Warrant Liabilities

The fair value of the Company’s warrant liabilities (refer to Note 8) recorded in the Company’s financial statements is determined using the Black-Scholes option pricing model and the quoted price of the Company’s common stock in an active market, volatility and expected life, is a Level 3 measurement. Volatility is based on the actual market activity of the Company’s stock. The expected life is based on the remaining contractual term of the warrants and the risk-free interest rate is based on the implied yield available on U.S. Treasury Securities with a maturity equivalent to the warrants’ expected life.

The following table presents financial assets and liabilities measured at fair value on a recurring basis as of April 30, 2020:

Total Carrying Value in Consolidated Balance Sheet

Quoted prices in active markets for identical assets or liabilities

(Level 1)

Significant other observable inputs

(Level 2)

Significant unobservable inputs

(Level 3)

(in thousands)

Warrant liabilities

The following table presents financial assets and liabilities measured at fair value on a recurring basis as of April 30, 2019:

	Total Carrying Value in Consolidated Balance Sheet		Quoted prices in active markets for identical assets or liabilities (Level 1)		Significant other observable inputs (Level 2)		Significant unobservable inputs (Level 3)
	(in thousands)

Warrant liabilities	$	6	$	-	$	-	$	6

The following table provides a summary of changes in the fair value of the warrant liabilities during the year ended April 30, 2020;

	Total Warrant Liability
	(in thousands)

Fair value – April 30, 2018	$	201
Change in fair value		(195	)
Fair value – April 30, 2019		6

Change in fair value		(6	)
Fair value – April 30, 2020	$	-

- Definition

The entire disclosure for the fair value of financial instruments (as defined), including financial assets and financial liabilities (collectively, as defined), and the measurements of those instruments as well as disclosures related to the fair value of non-financial assets and liabilities. Such disclosures about the financial instruments, assets, and liabilities would include: (1) the fair value of the required items together with their carrying amounts (as appropriate); (2) for items for which it is not practicable to estimate fair value, disclosure would include: (a) information pertinent to estimating fair value (including, carrying amount, effective interest rate, and maturity, and (b) the reasons why it is not practicable to estimate fair value; (3) significant concentrations of credit risk including: (a) information about the activity, region, or economic characteristics identifying a concentration, (b) the maximum amount of loss the entity is exposed to based on the gross fair value of the related item, (c) policy for requiring collateral or other security and information as to accessing such collateral or security, and (d) the nature and brief description of such collateral or security; (4) quantitative information about market risks and how such risks are managed; (5) for items measured on both a recurring and nonrecurring basis information regarding the inputs used to develop the fair value measurement; and (6) for items presented in the financial statement for which fair value measurement is elected: (a) information necessary to understand the reasons for the election, (b) discussion of the effect of fair value changes on earnings, (c) a description of [similar groups] items for which the election is made and the relation thereof to the balance sheet, the aggregate carrying value of items included in the balance sheet that are not eligible for the election; (7) all other required (as defined) and desired information.

+ References + Details

Income Taxes

12 Months Ended

Apr. 30, 2020

Income Tax Disclosure [Abstract]

Income Taxes

(14) Income Taxes-

Loss before income taxes for the years ended April 30, 2020 and 2019 consisted of the following components:

	April 30, 2020			April 30, 2019
	(in thousands)

Domestic	$	(10,985	)	$	(12,860	)
Foreign		(262	)		(236	)
Total loss before income taxes	$	(11,247	)	$	(13,096	)

The income tax benefit for the years ended April 30, 2020 and 2019 consist of state income tax benefits of $0.9 million in each year from the sale of New Jersey net operating losses and research and development credits.

Tax Rate Reconciliation

The effective income tax rate differed from the percentages computed by applying the US federal income tax rate for the periods ended April 30, 2020 and 2019 to loss before income taxes as a result of the following:

	April 30, 2020			April 30, 2019

Computed expected tax (benefit)		(21.0	)%		(21.0	)%
Increase(reduction) in income taxes resulting from:
State income taxes, net of federal (benefit)		2.9	%		0.8	%
Federal research and development tax credits		(0.5	)%		(1.5	)%
Foreign rate differential		5.2	%		0.2	%
Other non-deductible expenses		0.0	%		0.1	%
Proceeds of sale of New Jersey tax (benefits)		(8.0	)%		(6.5	)%
Other		5.2	%		0.6	%
Increase in valuation allowance		8.3	%		20.8	%
Income tax (benefit)		(7.9	)%		(6.5	)%

Significant Components of Deferred Taxes

The tax effects of temporary differences and carry forwards that give rise to the Company’s deferred tax assets and deferred tax liabilities are presented below.

	April 30, 2020			April 30, 2019
	(in thousands)

Deferred tax assets:
Federal net operating loss carryforwards	$	33,740		$	32,025
Foreign net operating loss carryforwards		3,307			3,641
State operating loss carryforwards		1,598			1,653
Federal and New Jersey research and development tax credits		3,076			3,315
Stock compensation		311			486
Accrued expenses		131			145
Other		595			443
Net deferred tax assets before valuation allowance		42,758			41,708
Valuation allowance		(42,431	)		(41,708	)
Deferred tax assets		327			-

Deferred tax liability:
Lease liability		327			-
Net deferred tax assets	$	-		$	-

In assessing the realizability of deferred tax assets, management considers whether it is more likely than not that some portion or all of the deferred tax assets will not be realized. The ultimate realization of deferred tax assets is dependent upon the generation of future taxable income during the periods in which those temporary differences and carry forwards become deductible or are utilized. As of April 30, 2020 and 2019, based upon the level of historical taxable losses, valuation allowances of $42.4 million and $41.7 million, respectively, were recorded to fully offset deferred tax assets. The valuation allowance increased $0.7 million during the year ended April 30, 2020 and decreased $2.5 million during the year ended 2019 respectively.

As of April 30, 2020, the Company had net operating loss carry forwards for federal income tax purposes of approximately $160.7 million, which begin to expire in fiscal 2021; $22.6 million of the federal carryforward has no expiration, but the deductibility of such federal net operating losses may be limited to 80% of our taxable income in future years. The Company also had federal research and development tax credit carry forwards of approximately $3.0 million as of April 30, 2020, which begins to expire in 2021. The Tax Reform Act of 1986 contains provisions that limit the utilization of net operating loss and tax credit carry forwards if there has been an ownership change, as defined. The Company has determined that such an ownership change, as described in Section 382 of the Internal Revenue Code, occurred in conjunction with the Company’s U.S. initial public offering in April 2007. The Company’s annual Section 382 limitation is approximately $3.3 million. The Section 382 limitation is cumulative from year to year, and thus, to the extent net operating loss or other credit carry forwards are not utilized up to the amount of the available annual limitation, the limitation is carried forward and added to the following year’s available limitation. Such limitation only applies to net operating losses incurred in periods prior to the ownership change. The Company has not performed additional analysis on ownership changes that may have occurred subsequently to further limit the ability to utilize net tax attributes. As of April 30, 2020, the Company had state net operating loss carry forwards of approximately $22.5 million which begin to expire in 2039, which also may be limited to utilization limitations. As of April 30, 2020, the Company had foreign net operating loss carry forwards of approximately $16.3 million. The ability to utilize these carry forwards may also be limited in the event of a significant change to ownership.

New Jersey Net Operating Loss

During the years ended April 30, 2020 and 2019, the Company sold New Jersey State net operating losses and research and development credits in the amount of $10.0 million and $9.1 million, respectively, resulting in the recognition of income tax benefits of $0.9 million and $0.9 million, respectively, recorded in the Company’s Statement of Operations.

Uncertain Tax Positions

The Company applies the guidance issued by the FASB for the accounting and reporting of uncertain tax positions. The guidance requires the Company to recognize in its consolidated financial statements the impact of a tax position if that position is more likely than not to be sustained upon examination, based on the technical merits of the position. The Company is currently undergoing an income tax audit in Spain for the period from 2011 to 2014, when the Company’s Spanish branch was closed (see Note 15 to the Consolidated Financial Statements). At April 30, 2020 and 2019, the Company had no other unrecognized tax positions. The Company does not expect any material increase or decrease in its income tax expense in the next twelve months, related to examinations or uncertain tax positions. U.S. federal and state income tax returns were audited through fiscal 2014 and fiscal 2010 respectively. Net operating loss and credit carry forwards since inception remain open to examination by taxing authorities and will continue to remain open for a period of time after utilization.

The Company does not have any interest or penalties accrued related to uncertain tax positions as it does not have any unrecognized tax benefits.

- Definition

The entire disclosure for income taxes. Disclosures may include net deferred tax liability or asset recognized in an enterprise's statement of financial position, net change during the year in the total valuation allowance, approximate tax effect of each type of temporary difference and carryforward that gives rise to a significant portion of deferred tax liabilities and deferred tax assets, utilization of a tax carryback, and tax uncertainties information.

+ References + Details

Commitments and Contingencies

12 Months Ended

Apr. 30, 2020

Commitments and Contingencies Disclosure [Abstract]

Commitments and Contingencies

(15) Commitments and Contingencies

Employment Litigation

On June 10, 2014, the Company announced that it had terminated Charles Dunleavy as its Chief Executive Officer and as an employee of the Company for cause, effective June 9, 2014, and that Mr. Dunleavy had also been removed from his position as Chairman of the Board of Directors. On June 17, 2014, Mr. Dunleavy wrote to the Company stating that he had retained counsel to represent him in connection with an alleged wrongful termination of his employment. On July 28, 2014, Mr. Dunleavy resigned from the Board and the boards of directors of the Company’s subsidiaries. In 2014, the Company and Mr. Dunleavy entered into a tolling agreement with respect to his alleged employment claims pending resolution of a securities class action and shareholder derivative litigation. The securities class action was resolved in November 2017 and the derivatives litigation was resolved in June 2018.

On August 28, 2018, counsel for Mr. Dunleavy filed a demand for arbitration, captioned Charles F. Dunleavy v. Ocean Power Technologies, Inc., Case No. 01-18-0003-2374, before the American Arbitration Association in New Jersey. The demand names Ocean Power Technologies, Inc. as the respondent and alleges various claims and seeks declaratory relief and permanent injunction. The demand seeks damages in the amount of $5 million for compensatory and punitive damages, plus interest and attorneys’ fees as well as certain equitable relief. On November 8, 2018, the Company through counsel responded to the demand for arbitration, denied all allegations, and asserted various affirmative defenses. On April 5, 2019, a three-person arbitration panel scheduled the discovery process to run from April 12, 2019 until November 9, 2019, set a pre-hearing case management conference for October 14, 2019, and set the hearing for December 9-13, 2019. On September 30, 2019, the parties completed the factual discovery process and the Company identified its expert witnesses. On October 14, 2019, the parties participated in a pre-hearing case management conference with arbitration panel and altered slightly the dates for the hearing. The hearing was conducted between December 9-11, 2019, and between December 16-18, 2019, and on December 18, 2019 the panel decided to continue the hearing for at least another day of testimony. The final day of hearing has now been scheduled for July 15, 2020, and the hearing will be conducted in Princeton, New Jersey. As of April 30, 2020, the Company has not accrued any provision related to this matter since it is not probable and cannot reasonably estimate the loss contingency.

NASDAQ Delisting Notification

On March 3, 2020, the Company received a notification from the NASDAQ Stock Market (the “NASDAQ”) indicating that the minimum bid price of the Company’s common stock has been below $1.00 per share for 30 consecutive business days and as a result, the Company is not in compliance with the minimum bid price requirement for continued listing. The NASDAQ notice has no immediate effect on the listing or trading of the Company’s common stock. Under the NASDAQ Listing Rules, the Company has a grace period of 180 calendar days, or until August 31, 2020, in which to regain compliance with the minimum bid price rule. To regain compliance, the closing bid price of the Company’s common stock must meet or exceed $1.00 per share for a minimum of ten consecutive business days during this grace period. On April 20, 2020, the Company received a written notice from NASDAQ indicating that, as a result of the tolling of the bid price requirements due to COVID-19, the period within which the Company has to regain compliance was extended from August 31, 2020 to November 13, 2020.

Spain Income Tax Audit

The Company is currently undergoing an income tax audit in Spain for the period from 2011 to 2014, the Spanish tax inspector has raised questions with respect to the Company’s recognition of funds received during this time period from a governmental grant from the European Commission in connection with the Waveport project. It is anticipated that the Company will be assessed a penalty relating to these tax years. The Company has estimated this penalty to be $177,000 and as of April 30, 2020 and 2019 has recorded the penalty in Accrued expenses in the Consolidated Balance Sheet.

Operating Segments and Geographic Information

12 Months Ended

Apr. 30, 2020

Segment Reporting [Abstract]

Operating Segments and Geographic Information

(16) Operating Segments and Geographic Information

The Company’s business consists of one segment as this represents management’s view of the Company’s operations. The Company operates on a worldwide basis with one operating company in the US and operating subsidiaries in the UK and in Australia. Revenues and expenses are generally attributed to the operating unit that bills the customers. Geographic information is as follows:

	Year Ended April 30, 2020
	North America			Europe			Asia and Australia			Total
	(in thousands)

Revenues from external customers	$	1,682		$	-		$	-		$	1,682
Operating loss		(11,110	)		(234	)		(21	)		(11,365	)
Long-lived assets		499			-			-			499
Total assets		13,251			36			251			13,538

	Year Ended April 30, 2019
	North America			Europe			Asia and Australia			Total
	(in thousands)

Revenues from external customers	$	632		$	-		$	-		$	632
Operating loss		(13,045	)		(204	)		(22	)		(13,271	)
Long-lived assets		592			-			-			592
Total assets		18,028			49			289			18,366

- Definition

The entire disclosure for reporting segments including data and tables. Reportable segments include those that meet any of the following quantitative thresholds a) it's reported revenue, including sales to external customers and intersegment sales or transfers is 10 percent or more of the combined revenue, internal and external, of all operating segments b) the absolute amount of its reported profit or loss is 10 percent or more of the greater, in absolute amount of 1) the combined reported profit of all operating segments that did not report a loss or 2) the combined reported loss of all operating segments that did report a loss c) its assets are 10 percent or more of the combined assets of all operating segments.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 280
-SubTopic 10
-Section 50
-Paragraph 31
-URI http://asc.fasb.org/extlink&oid=120311839&loc=d3e8924-108599

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 280
-SubTopic 10
-Section 50
-Paragraph 34
-URI http://asc.fasb.org/extlink&oid=120311839&loc=d3e8981-108599

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
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-Section 50
-Paragraph 21
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-URI http://asc.fasb.org/extlink&oid=120311839&loc=d3e8721-108599

Reference 4: http://www.xbrl.org/2003/role/disclosureRef
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-Name Accounting Standards Codification
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-URI http://asc.fasb.org/extlink&oid=120311839&loc=d3e9031-108599

Reference 5: http://www.xbrl.org/2003/role/disclosureRef
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-Name Accounting Standards Codification
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-SubTopic 10
-Section 50
-Paragraph 32
-Subparagraph (f)
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Reference 6: http://www.xbrl.org/2003/role/disclosureRef
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-Name Accounting Standards Codification
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-Subparagraph (e)
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Reference 7: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 280
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-Section 50
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Reference 8: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 280
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-Section 50
-Paragraph 41
-URI http://asc.fasb.org/extlink&oid=120311839&loc=d3e9038-108599

Reference 9: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 280
-SubTopic 10
-Section 50
-Paragraph 32
-Subparagraph (d)
-URI http://asc.fasb.org/extlink&oid=120311839&loc=d3e8933-108599

Reference 10: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 280
-SubTopic 10
-Section 50
-Paragraph 22
-URI http://asc.fasb.org/extlink&oid=120311839&loc=d3e8736-108599

Reference 11: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 280
-SubTopic 10
-Section 50
-Paragraph 42
-URI http://asc.fasb.org/extlink&oid=120311839&loc=d3e9054-108599

Reference 12: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 280
-SubTopic 10
-Section 50
-Paragraph 15
-URI http://asc.fasb.org/extlink&oid=120311839&loc=d3e8657-108599

Reference 13: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 280
-SubTopic 10
-Section 50
-Paragraph 21
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=120311839&loc=d3e8721-108599

Reference 14: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 280
-URI http://asc.fasb.org/topic&trid=2134510

+ Details

Subsequent Event

12 Months Ended

Apr. 30, 2020

Subsequent Events [Abstract]

Subsequent Event

(17) Subsequent Event

As a result of the COVID-19 pandemic, the U.S. Government passed the CARES Act. On May 3, 2020, the Company signed a PPP loan with Santander as the lender for $890,347 in support through the Small Business Association (“SBA”) under the PPP Loan. The PPP Loan will be unsecured and evidenced by a note in favor of Santander as the lender (the “Note”) and governed by a Loan Agreement with Santander (the “Loan Agreement”). The Company received the proceeds on May 5, 2020. The SBA allows loan forgiveness for costs incurred and paid for a) payroll costs, b) interest on any real or personal property mortgage incurred prior to February 15, 2020, c) rent on any lease in force prior to February 15, 2020, and d) utility payments for which service began before February 15, 2020.

Summary of Significant Accounting Policies (Policies)

12 Months Ended

Apr. 30, 2020

Accounting Policies [Abstract]

Consolidation

(a) Consolidation

Use of Estimates

(b) Use of Estimates

Revenue Recognition

(c) Revenue Recognition

Cash and Cash Equivalents, Restricted Cash and Security Agreements

(d) Cash and Cash Equivalents, Restricted Cash and Security Agreements

Cash and Cash Equivalents

	April 30, 2020		April 30, 2019
	(in thousands)

Checking and savings accounts	$	1,551	$	860
Money market account		8,451		15,800
	$	10,002	$	16,660

Restricted Cash and Security Agreements

A portion of the Company’s cash is restricted under the terms of various security agreements.

	April 30, 2020		April 30, 2019
	(in thousands)

Barclay’s Bank Agreement	$	-	$	344
Santander Bank		928		155
	$	928	$	499

	April 30, 2020		April 30, 2019
	(in thousands)

Cash and cash equivalents	$	10,002	$	16,660
Restricted cash- short term		707		344
Restricted cash- long term		221		155
	$	10,930	$	17,159

Property and Equipment

(e) Property and Equipment

Description		Estimated useful life

Equipment		5 - 7 years
Computer equipment & software		3 years
Office furniture & fixtures		3 - 7 years
Equipment under capitalized lease		Over the life of the lease
Leasehold improvements		Shorter of the estimated useful life or lease term

Foreign Exchange Gains and Losses

(f) Foreign Exchange Gains and Losses

Concentration of Credit Risk

(g) Concentration of Credit Risk

	Twelve months ended April 30,
	2020			2019

Eni S.p.A.		10	%		54	%
Premier Oil UK Limited		9	%		33	%
EGP		72	%		4	%
Other		9	%		9	%
		100	%		100	%

Warrant Accounting

(h) Warrant Accounting

Net Loss Per Common Share

(i) Net Loss per Common Share

Share-Based Compensation

(j) Share-Based Compensation

	Twelve months ended April 30,
	2020		2019


Product development	$	89	$	29
Selling, general and administrative		251		266
Total share-based compensation expense	$	340	$	295

Deferred Rent

(k) Deferred Rent

Income Taxes

(l) Income Taxes

Accumulated Other Comprehensive Loss

(m) Accumulated Other Comprehensive Loss

Recently Issued Accounting Standards

(n) Recently Issued Accounting Standards

Summary of Significant Accounting Policies (Tables)

12 Months Ended

Apr. 30, 2020

Schedule of Cash and Cash Equivalents

The following table summarizes cash and cash equivalents for the years ended April 30, 2020 and 2019:

	April 30, 2020		April 30, 2019
	(in thousands)

Checking and savings accounts	$	1,551	$	860
Money market account		8,451		15,800
	$	10,002	$	16,660

Schedule of Cash and Cash Equivalents and Restricted Cash

The following table summarizes restricted cash for the years ended April 30, 2020 and 2019:

	April 30, 2020		April 30, 2019
	(in thousands)

Barclay’s Bank Agreement	$	-	$	344
Santander Bank		928		155
	$	928	$	499

Schedule of Property, Plant and Equipment, Useful Life

Description		Estimated useful life

Equipment		5 - 7 years
Computer equipment & software		3 years
Office furniture & fixtures		3 - 7 years
Equipment under capitalized lease		Over the life of the lease
Leasehold improvements		Shorter of the estimated useful life or lease term

Schedule of Revenue by Major Customers by Reporting Segments

	Twelve months ended April 30,
	2020			2019

Eni S.p.A.		10	%		54	%
Premier Oil UK Limited		9	%		33	%
EGP		72	%		4	%
Other		9	%		9	%
		100	%		100	%

Schedule of Employee Service Share-based Compensation, Allocation of Recognized Period Costs

The following table summarizes share-based compensation related to the Company’s share-based plans by expense category for the years ended April 30, 2020 and 2019:

	Twelve months ended April 30,
	2020		2019


Product development	$	89	$	29
Selling, general and administrative		251		266
Total share-based compensation expense	$	340	$	295

Restricted Cash [Member]

Schedule of Cash and Cash Equivalents and Restricted Cash

	April 30, 2020		April 30, 2019
	(in thousands)

Cash and cash equivalents	$	10,002	$	16,660
Restricted cash- short term		707		344
Restricted cash- long term		221		155
	$	10,930	$	17,159

Account Receivable, Contract Assets, and Contract Liabilities (Tables)

12 Months Ended

Apr. 30, 2020

Account Receivable Contract Assets And Contract Liabilities

Schedule of Accounts Receivable

Accounts receivable consisted of the following at April 30, 2020 and 2019.

	April 30, 2020			April 30, 2019
	(in thousands)

Opening balance	$	63		$	171
Amount invoiced to customers		1,386			857
Collections		(1,344	)		(965	)
Ending balance	$	105		$	63

Other Current Assets (Tables)

12 Months Ended

Apr. 30, 2020

Deferred Costs, Capitalized, Prepaid, and Other Assets Disclosure [Abstract]

Schedule of Other Current Assets

Other current assets consist of the following at April 30, 2020 and 2019:

	April 30, 2020		April 30, 2019
	(in thousands)

Deposits	$	60	$	63
Other receivables		2		44
Prepaid insurance		124		93
Prepaid offering costs		275		144
Prepaid expenses- other		127		193
	$	588	$	537

Property and Equipment (Tables)

12 Months Ended

Apr. 30, 2020

Property, Plant and Equipment [Abstract]

Schedule of Components of Property and Equipment

The components of property and equipment as of April 30, 2020 and 2019 consisted of the following:

	April 30, 2020			April 30, 2019
	(in thousands)

Equipment	$	342			339
Computer equipment & software		486			558
Office furniture & equipment		339			341
Leasehold improvements		474			474
Equipment under capitalized lease		-			103
Construction in process		15			15
	$	1,656		$	1,830
Less: accumulated depreciation		(1,157	)		(1,238	)
	$	499		$	592

Leases (Tables)

12 Months Ended

Apr. 30, 2020

Leases [Abstract]

Schedule of Right-of Use Assets and Lease Liabilities

Information related to the Company’s right-of use assets and lease liabilities as of April 30, 2020 is as follows:

	April 30, 2020
		(in thousands)

Operating lease:
Operating right-of-use asset, net	$	1,165

Right-of-use liability- current		229
Right-of-use liability- long term		1,078
Total lease liability	$	1,307

Weighted average remaining lease term- operating leases		4.49 years
Weighted average discount rate- operating leases		8.5	%

Schedule of Remaining Lease Payments Under Operating Lease

Total remaining lease payments under the Company’s operating leases are as follows:

	April 30, 2020
		(in thousands)

2021		331
2022		341
2023		352
2024		362
Thereafter		184
Total future minimum lease payments	$	1,570
Less imputed interest		(263	)
Total	$	1,307

Schedule of Future Minimum Lease Payments Under Operating Lease

Future minimum lease payments under the Company’s operating lease as of April 30, 2019 were as follows:

	April 30, 2019
		(in thousands)

2020		322
2021		331
2022		341
2023		352
2024		362
Thereafter		184
	$	1,892

Accrued Expenses (Tables)

12 Months Ended

Apr. 30, 2020

Payables and Accruals [Abstract]

Schedule of Accrued Expenses

Accrued expenses consisted of the following at April 30, 2020 and 2019:

	April 30, 2020		April 30, 2019
	(in thousands)

Project costs	$	48	$	9
Contract loss reserve		216		211
Employee incentive payments		-		580
Accrued salary and benefits		483		500
Legal and accounting fees		283		273
Accrued taxes payable		177		177
Other		146		188
	$	1,353	$	1,938

Warrants (Tables)

12 Months Ended

Apr. 30, 2020

Warrant [Member]

Schedule of Fair Value Assumptions Used

The Company determined the fair value using the Black-Scholes option pricing model with the following assumptions for the period ended April 30, 2020 and 2019:

	April 30, 2020			April 30, 2019

Dividend rate		0.0	%		0.0	%
Risk-free rate		0.17% - 0.19	%		2.2% - 2.3	%
Expected life (years)		1.2 - 1.6			2.2 - 2.6
Expected volatility		81.8% - 112.7	%		110.0% - 153.4	%

Stock-Based Compensation (Tables)

12 Months Ended

Apr. 30, 2020

Schedule of Share-based Payment Award, Stock Options, Valuation Assumptions

	Twelve months ended April 30,
	2020			2019

Risk-free interest rate		1.7	%		2.7	%
Expected dividend yield		0.0	%		0.0	%
Expected life (in years)		5.5- 5.7			5.5
Expected volatility		127.6% - 128.2	%		126.4	%

Schedule of Stock Option Activity

A summary of stock options under our stock incentive plans is detailed in the following table.

						Weighted
						Average
				Weighted		Remaining
	Shares			Average		Contractual
	Underlying			Exercise		Term
	Options			Price		(In Years)
Outstanding as of April 30, 2019		65,572		$	21.08		8.9
Granted		493,000		$	1.05
Exercised		-		$	-
Cancelled/forfeited		(3,097	)	$	44.32
Outstanding as of April 30, 2020		555,475		$	3.19		9.5
Exercisable as of April 30, 2020		62,475		$	20.09		7.9

Schedule of Non-vested Restricted Stock Activity

A summary of unvested restricted stock under our stock incentive plans is as follows:

				Weighted
	Number			Average Price per
	of Shares			Share

Issued and unvested at April 30, 2019		4,506		$	30.08
Granted		13,513		$	1.48
Vested		(4,380	)	$	30.14
Cancelled/forfeited		(126	)	$	28.00
Issued and unvested at April 30, 2020		13,513		$	1.48

Performance Stock Options [Member]

Schedule of Share-based Payment Award, Stock Options, Valuation Assumptions

The Company determined these awards contain a market- based condition and estimated the fair value using the Monte Carlo simulation model with the following assumptions:

Risk-free interest rate	2.3	%
Expected dividend yield	0.0	%
Expected life (in years)	10.0
Expected volatility	115.0	%

Fair Value Measurements (Tables)

12 Months Ended

Apr. 30, 2020

Fair Value Disclosures [Abstract]

Schedule of Fair Value, Assets and Liabilities Measured on Recurring Basis

The following table presents financial assets and liabilities measured at fair value on a recurring basis as of April 30, 2020:

Total Carrying Value in Consolidated Balance Sheet

Quoted prices in active markets for identical assets or liabilities

(Level 1)

Significant other observable inputs

(Level 2)

Significant unobservable inputs

(Level 3)

(in thousands)

Warrant liabilities

The following table presents financial assets and liabilities measured at fair value on a recurring basis as of April 30, 2019:

	Total Carrying Value in Consolidated Balance Sheet		Quoted prices in active markets for identical assets or liabilities (Level 1)		Significant other observable inputs (Level 2)		Significant unobservable inputs (Level 3)
	(in thousands)

Warrant liabilities	$	6	$	-	$	-	$	6

Summary of Changes on Value of Warrant Liability Using Significant Unobservable Inputs

The following table provides a summary of changes in the fair value of the warrant liabilities during the year ended April 30, 2020;

	Total Warrant Liability
	(in thousands)

Fair value – April 30, 2018	$	201
Change in fair value		(195	)
Fair value – April 30, 2019		6

Change in fair value		(6	)
Fair value – April 30, 2020	$	-

Income Taxes (Tables)

12 Months Ended

Apr. 30, 2020

Income Tax Disclosure [Abstract]

Schedule of Components of Loss Before Income Taxes

Loss before income taxes for the years ended April 30, 2020 and 2019 consisted of the following components:

	April 30, 2020			April 30, 2019
	(in thousands)

Domestic	$	(10,985	)	$	(12,860	)
Foreign		(262	)		(236	)
Total loss before income taxes	$	(11,247	)	$	(13,096	)

Schedule of Effective Income Tax Rate Reconciliation

	April 30, 2020			April 30, 2019

Computed expected tax (benefit)		(21.0	)%		(21.0	)%
Increase(reduction) in income taxes resulting from:
State income taxes, net of federal (benefit)		2.9	%		0.8	%
Federal research and development tax credits		(0.5	)%		(1.5	)%
Foreign rate differential		5.2	%		0.2	%
Other non-deductible expenses		0.0	%		0.1	%
Proceeds of sale of New Jersey tax (benefits)		(8.0	)%		(6.5	)%
Other		5.2	%		0.6	%
Increase in valuation allowance		8.3	%		20.8	%
Income tax (benefit)		(7.9	)%		(6.5	)%

Schedule of Deferred Tax Assets and Liabilities

The tax effects of temporary differences and carry forwards that give rise to the Company’s deferred tax assets and deferred tax liabilities are presented below.

	April 30, 2020			April 30, 2019
	(in thousands)

Deferred tax assets:
Federal net operating loss carryforwards	$	33,740		$	32,025
Foreign net operating loss carryforwards		3,307			3,641
State operating loss carryforwards		1,598			1,653
Federal and New Jersey research and development tax credits		3,076			3,315
Stock compensation		311			486
Accrued expenses		131			145
Other		595			443
Net deferred tax assets before valuation allowance		42,758			41,708
Valuation allowance		(42,431	)		(41,708	)
Deferred tax assets		327			-

Deferred tax liability:
Lease liability		327			-
Net deferred tax assets	$	-		$	-

Operating Segments and Geographic Information (Tables)

12 Months Ended

Apr. 30, 2020

Segment Reporting [Abstract]

Schedule of Revenue from External Customers and Long-Lived Assets, by Geographical Areas

	Year Ended April 30, 2020
	North America			Europe			Asia and Australia			Total
	(in thousands)

Revenues from external customers	$	1,682		$	-		$	-		$	1,682
Operating loss		(11,110	)		(234	)		(21	)		(11,365	)
Long-lived assets		499			-			-			499
Total assets		13,251			36			251			13,538

	Year Ended April 30, 2019
	North America			Europe			Asia and Australia			Total
	(in thousands)

Revenues from external customers	$	632		$	-		$	-		$	632
Operating loss		(13,045	)		(204	)		(22	)		(13,271	)
Long-lived assets		592			-			-			592
Total assets		18,028			49			289			18,366

Background and Liquidity (Details Narrative) - USD ($)						3 Months Ended	12 Months Ended
Background and Liquidity (Details Narrative) - USD ($)	May 05, 2020	Oct. 24, 2019	Apr. 08, 2019	Jan. 07, 2019	Aug. 13, 2018	Apr. 30, 2020	Apr. 30, 2020	Apr. 30, 2019
Accumulated deficit						$ (220,136,000)	$ (220,136,000)	$ (209,784,000)
Cash, cash equivalents and restricted cash, at carrying value						$ 10,930,000	10,930,000	17,159,000
Revenues							$ 1,700,000	$ 600,000
Number of common stock shares sold			1,542,000
Aggregate offering price			$ 15,700,000
Pre-funded Warrants [Member]
Warrant to purchase shares common stock			3,385,680
Over-Allotment Option [Member]
Number of common stock shares sold			642,000
Stock Purchase Agreement [Member] \| Aspire Capital Fund, LLC [Member]
Aggregate purchase of common stock		$ 10,000,000			$ 10,000,000
Percentage of outstanding common stock limit for shareholder approval					19.99%
Number of shares can be issued based upon outstanding percentage					183,591
Common stock issued for commitment fee					21,429
Number of common stock shares sold		162,162
Proceeds from issuance or sale of equity, net of issuance costs		$ 949,259
Combined purchase price per share		$ 5.85
Stock Purchase Agreement [Member] \| Aspire Capital Fund, LLC [Member] \| December 20, 2019 [Member]
Stock issued for new issue, shares		5,400,000
Stock Purchase Agreement [Member] \| Aspire Capital Fund, LLC [Member] \| Maximum [Member]
Percentage of outstanding common stock limit for shareholder approval		19.99%
Number of shares can be issued based upon outstanding percentage		1,219,010
Common stock issued for commitment fee		194,805
Combined purchase price per share						$ 0.82	$ 0.82
Stock issued for new issue, shares						1,399,205	1,399,205
Stock issued for new issue, value						$ 1,100,000	$ 1,100,000
Securities Purchase Agreement [Member]
Warrant to purchase shares common stock			4,927,680
2019 ATM Facility [Member] \| A.G.P./ Alliance Global Partners [Member]
Number of common stock shares sold							5,101,405
Proceeds from issuance or sale of equity, net of issuance costs							$ 3,800,000
Combined purchase price per share						$ 0.74	$ 0.74
Aggregate offering price				$ 25,000,000
Payment of sales commission							$ 122,530
Subsequent Event [Member] \| Paycheck Protection Program [Member]
Proceeds from loan	$ 900,000

Summary of Significant Accounting Policies (Details Narrative)		12 Months Ended
	Mar. 31, 2017 USD ($) ft²	Apr. 30, 2020 USD ($) shares	Apr. 30, 2019 USD ($) shares	Apr. 30, 2020 EUR (€)	May 02, 2019 USD ($)
Performance obligation revenue of next twelve months		$ 1,000,000
Revenue remaining performance obligation, percentage		79.00%
Revenue remaining performance obligation		$ 800,000
Antidilutive securities excluded from computation of earnings per share, shares \| shares		5,564,438	5,013,981
Share based compensation		$ 300,000	$ 300,000
Right-of-use asset		1,165,000
Lease liability		$ 1,307,000
ASU 2016-02 [Member]
Right-of-use asset					$ 1,400,000
Lease liability					1,500,000
Deferred rent					39,000
Unamortized lease incentive receivable					$ 108,000
Monroe Township [Member]
Term of lease	7 years	7 years		7 years
Area of land \| ft²	56,000
Tenant improvement work	$ 137,563
Santander Bank [Member] \| Letter 2 [Member] \| March 2020 [Member]
Letters of credit outstanding, amount		$ 322,734
Santander Bank [Member] \| Letter 2 [Member] \| May 2020 [Member]
Letters of credit outstanding, amount		$ 64,547
Line of credit expiration period		Sep. 30, 2021
Foreign Financial Institutions [Member]
Cash		$ 300,000
One Agreement [Member] \| Barclays Bank [Member]
Long-term line of credit		$ 400,000
Line of credit facility, commitment fee percentage		1.00%
Letters of credit outstanding, amount
One Agreement [Member] \| Barclays Bank [Member] \| Euro [Member]
Long-term line of credit \| €				€ 300,000
Letters of credit outstanding, amount
Other Agreement [Member] \| Santander Bank [Member] \| Letter 1 [Member]
Letters of credit outstanding, amount		$ 125,690
Line of credit expiration period		Feb. 21, 2021
Other Agreement [Member] \| Santander Bank [Member] \| Letter 2 [Member]
Letters of credit outstanding, amount		$ 645,467

Summary of Significant Accounting Policies - Schedule of Cash and Cash Equivalents (Details) - USD ($) $ in Thousands	Apr. 30, 2020	Apr. 30, 2019
Cash and cash equivalents	$ 10,002	$ 16,660
Checking and Savings Accounts [Member]
Cash and cash equivalents	1,551	860
Money Market Account [Member]
Cash and cash equivalents	$ 8,451	$ 15,800

Summary of Significant Accounting Policies - Schedule of Cash and Cash Equivalents and Restricted Cash (Details) - USD ($)	Apr. 30, 2020	Apr. 30, 2019
Restricted Cash	$ 928,000	$ 499,000
Cash and Cash Equivalents	10,002,000	16,660,000
Restricted cash- short term	707,000	344,000
Restricted cash- long term	221,000	155,000
Cash, Cash Equivalents, Restricted Cash and Restricted Cash Equivalents	10,930,000	17,159,000
Barclay's Bank Agreement [Member]
Restricted Cash		344,000
Santander Bank [Member]
Restricted Cash	$ 928,000	$ 155,000

Summary of Significant Accounting Policies - Schedule of Property, Plant and Equipment, Useful Life (Details)	12 Months Ended
	Apr. 30, 2020	Apr. 30, 2019
Computer Equipment & Software [Member]
Property and equipment, useful life (Year)	3 years
Equipment Under Capitalized Lease [Member]
Property and equipment, useful life	Over the life of the lease
Leasehold Improvements [Member]
Property and equipment, useful life	Shorter of the estimated useful life or lease term
Minimum [Member] \| Equipment [Member]
Property and equipment, useful life (Year)		5 years
Minimum [Member] \| Office Furniture & Fixtures [Member]
Property and equipment, useful life (Year)	3 years
Maximum [Member] \| Equipment [Member]
Property and equipment, useful life (Year)	7 years
Maximum [Member] \| Office Furniture & Fixtures [Member]
Property and equipment, useful life (Year)	7 years

Summary of Significant Accounting Policies - Schedule of Revenue by Major Customers by Reporting Segments (Details) - Sales Revenue, Net [Member] - Customer Concentration Risk [Member]	12 Months Ended
	Apr. 30, 2020	Apr. 30, 2019
Revenues, percentage	100.00%	100.00%
Eni S.P.A [Member]
Revenues, percentage	10.00%	54.00%
Premier Oil UK Limited [Member]
Revenues, percentage	9.00%	33.00%
EGP [Member]
Revenues, percentage	72.00%	4.00%
Other [Member]
Revenues, percentage	9.00%	9.00%

Summary of Significant Accounting Policies - Schedule of Employee Service Share-based Compensation, Allocation of Recognized Period Costs (Details) - USD ($) $ in Thousands	12 Months Ended
	Apr. 30, 2020	Apr. 30, 2019
Total share-based compensation expense	$ 340	$ 295
Product Development [Member]
Total share-based compensation expense	89	29
Selling, General and Administrative [Member]
Total share-based compensation expense	$ 251	$ 266

Account Receivable, Contract Assets, and Contract Liabilities - Schedule of Accounts Receivable (Details) - USD ($) $ in Thousands	12 Months Ended
	Apr. 30, 2020	Apr. 30, 2019
Account Receivable Contract Assets And Contract Liabilities
Opening balance	$ 63	$ 171
Amount invoiced to customer	1,386	857
Collections	(1,344)	(965)
Ending balance	$ 105	$ 63

Other Current Assets - Schedule of Other Current Assets (Details) - USD ($) $ in Thousands	Apr. 30, 2020	Apr. 30, 2019
Deferred Costs, Capitalized, Prepaid, and Other Assets Disclosure [Abstract]
Deposits	$ 60	$ 63
Other receivables	2	44
Prepaid insurance	124	93
Prepaid offering costs	275	144
Prepaid expenses- other	127	193
Other current assets	$ 588	$ 537

Property and Equipment (Details Narrative) - USD ($) $ in Thousands	12 Months Ended
	Apr. 30, 2020	Apr. 30, 2019
Property, Plant and Equipment [Abstract]
Depreciation expense	$ 200	$ 200

Property and Equipment - Schedule of Components of Property and Equipment, Net (Details) - USD ($) $ in Thousands	Apr. 30, 2020	Apr. 30, 2019
Property and equipment, gross	$ 1,656	$ 1,830
Less: accumulated depreciation	(1,157)	(1,238)
Property and equipment, net	499	592
Equipment [Member]
Property and equipment, gross	342	339
Computer Equipment & Software [Member]
Property and equipment, gross	486	558
Office Furniture & Equipment [Member]
Property and equipment, gross	339	341
Leasehold Improvements [Member]
Property and equipment, gross	474	474
Equipment Under Capitalized Lease [Member]
Property and equipment, gross		103
Construction in Process [Member]
Property and equipment, gross	$ 15	$ 15

Leases (Details Narrative) $ in Thousands	12 Months Ended
Leases (Details Narrative) $ in Thousands	Apr. 30, 2020 USD ($) Integer	Mar. 31, 2017
Number of active lease arrangement \| Integer	1
Operating lease straight-line expense	$ 317
Operating leases cash payments	$ 322
Monroe Township [Member]
Term of lease	7 years	7 years
Option to extend lease	The initial lease term is for 7 years with an option to extend the lease for another 5 years.

Leases - Schedule of Right-of Use Assets and Lease Liabilities (Details) - USD ($)	Apr. 30, 2020	Apr. 30, 2019
Leases [Abstract]
Operating right-of-use asset, net	$ 1,165,000
Right-of-use liability- current	229,000
Right-of-use liability- long term	1,078,000
Total lease liability	$ 1,307,000
Weighted average remaining lease term- operating leases	4 years 5 months 27 days
Weighted average discount rate- operating leases	8.50%

Leases - Schedule of Remaining Lease Payments Under Operating Lease (Details)	Apr. 30, 2020 USD ($)
Leases [Abstract]
2021	$ 331,000
2022	341,000
2023	352,000
2024	362,000
Thereafter	184,000
Total future minimum lease payments	1,570,000
Less imputed interest	(263,000)
Total	$ 1,307,000

Leases - Schedule of Future Minimum Lease Payments Under Operating Lease (Details) $ in Thousands	Apr. 30, 2019 USD ($)
Leases [Abstract]
2020	$ 322
2021	331
2022	341
2023	352
2024	362
Thereafter	184
Future lease payments	$ 1,892

Accrued Expenses - Schedule of Accrued Expenses (Details) - USD ($) $ in Thousands	Apr. 30, 2020	Apr. 30, 2019
Payables and Accruals [Abstract]
Project costs	$ 48	$ 9
Contract loss reserve	216	211
Employee incentive payments		580
Accrued salary and benefits	483	500
Legal and accounting fees	283	273
Accrued taxes payable	177	177
Other	146	188
Accrued expenses total	$ 1,353	$ 1,938

Warrants (Details Narrative) - USD ($) $ / shares in Units, $ in Thousands				12 Months Ended
	Apr. 08, 2019	Jul. 22, 2016	Jun. 02, 2016	Apr. 30, 2020	Apr. 30, 2019
Warrant liabilities					$ 6
Unrealized gain on warrants				$ 6	$ 200
Pre-funded Warrants [Member]
Warrant to purchase shares common stock	3,385,680
Warrant exercise price per share	$ 0.01
Securities Purchase Agreement [Member]
Stock issued for new issue, shares	1,542,000		20,850
Warrant to purchase shares common stock	4,927,680		7,298
Class of warrant or right, number of securities called by each warrant or right			0.35
Combined purchase price per share			$ 92.00
Warrant exercise price per share	$ 3.85		$ 121.60
Class of warrant or right, expiration period	5 years		5 years
Number of exercised warrants
Second Amended Purchase Agreement [Member]
Stock issued for new issue, shares		29,750
Warrant to purchase shares common stock		8,925
Class of warrant or right, number of securities called by each warrant or right		0.30
Combined purchase price per share		$ 135.00
Warrant exercise price per share		$ 187.20
Class of warrant or right, expiration period		5 years

Warrants - Schedule of Fair Value Assumptions Used (Details)	Apr. 30, 2020	Apr. 30, 2019
Dividend Rate [Member]
Fair value measurement input, percentage	0.0	0.0
Risk Free Interest Rate [Member] \| Minimum [Member]
Fair value measurement input, percentage	0.17	2.2
Risk Free Interest Rate [Member] \| Maximum [Member]
Fair value measurement input, percentage	0.19	2.3
Expected Life (Years) [Member] \| Minimum [Member]
Fair value measurement expected life	1 year 2 months 12 days	2 years 2 months 12 days
Expected Life (Years) [Member] \| Maximum [Member]
Fair value measurement expected life	1 year 7 months 6 days	2 years 7 months 6 days
Expected Volatility [Member] \| Minimum [Member]
Fair value measurement input, percentage	81.8	110.0
Expected Volatility [Member] \| Maximum [Member]
Fair value measurement input, percentage	112.7	153.4

Preferred Stock (Details Narrative) - $ / shares	Apr. 30, 2020	Apr. 30, 2019
Equity [Abstract]
Preferred stock, shares authorized	5,000,000	5,000,000
Preferred stock, par value	$ 0.001	$ 0.001
Preferred stock, shares issued

Common Stock (Details Narrative) - USD ($)					3 Months Ended	12 Months Ended
Common Stock (Details Narrative) - USD ($)	Oct. 24, 2019	Apr. 08, 2019	Jan. 07, 2019	Aug. 13, 2018	Apr. 30, 2020	Apr. 30, 2020	Apr. 30, 2019
Common stock, shares authorized					100,000,000	100,000,000	100,000,000
Common stock, par value					$ 0.001	$ 0.001	$ 0.001
Common stock, shares issued					12,939,420	12,939,420	5,425,517
Number of common stock shares sold		1,542,000
Aggregate offering price		$ 15,700,000
Pre-funded Warrants [Member]
Warrant to purchase shares common stock		3,385,680
Over-Allotment Option [Member]
Number of common stock shares sold		642,000
Stock Purchase Agreement [Member] \| Aspire Capital Fund, LLC [Member]
Aggregate purchase of common stock	$ 10,000,000			$ 10,000,000
Percentage of outstanding common stock limit for shareholder approval				19.99%
Number of shares can be issued based upon outstanding percentage				183,591
Common stock issued for commitment fee				21,429
Number of common stock shares sold	162,162
Value of common stock shares sold, net of issuance costs	$ 949,259
Sale of stock, price per share	$ 5.85
Stock Purchase Agreement [Member] \| Aspire Capital Fund, LLC [Member] \| December 20, 2019 [Member]
Stock issued for new issue, shares	5,400,000
Stock Purchase Agreement [Member] \| Aspire Capital Fund, LLC [Member] \| Maximum [Member]
Percentage of outstanding common stock limit for shareholder approval	19.99%
Number of shares can be issued based upon outstanding percentage	1,219,010
Common stock issued for commitment fee	194,805
Sale of stock, price per share					$ 0.82	$ 0.82
Stock issued for new issue, shares					1,399,205	1,399,205
Stock issued for new issue, value					$ 1,100,000	$ 1,100,000
2019 ATM Facility [Member] \| A.G.P./ Alliance Global Partners [Member]
Number of common stock shares sold						5,101,405
Value of common stock shares sold, net of issuance costs						$ 3,800,000
Sale of stock, price per share					$ 0.74	$ 0.74
Aggregate offering price			$ 25,000,000
Payment of sales commission						$ 122,530
Securities Purchase Agreement [Member]
Warrant to purchase shares common stock		4,927,680

Treasury Shares (Details Narrative) - shares	12 Months Ended
Treasury Shares (Details Narrative) - shares	Apr. 30, 2020	Apr. 30, 2019
Equity [Abstract]
Treasury stock, shares, acquired	481	89

Share-Based Compensation (Details Narrative) - USD ($) $ / shares in Units, $ in Thousands	1 Months Ended	12 Months Ended
	Jan. 31, 2020	Apr. 30, 2020	Apr. 30, 2019	Dec. 20, 2019	Dec. 07, 2018	Jan. 18, 2018	Oct. 21, 2016	Dec. 31, 2015
Share-based compensation expense		$ 20
Unrecognized compensation cost related to non-vested stock options		$ 30
Share-based compensation cost expected to recognize weighted-average term		7 months 6 days
Restricted stock options, granted during period		51,547
Performance-based Stock Options [Member]
Share-based compensation weighted average per share fair value		$ 0.82
Employee Stock Option [Member]
Number of shares granted during the period		411,666	49,750
Share-based compensation weighted average per share fair value		$ 0.92	$ 7.15
Share-based compensation unvested shares of stock options		493,000
Share-based compensation intrinsic value of outstanding		$ 0
Share-based compensation options, exercisable intrinsic value		$ 0
Share-based compensation weighted average remaining contractual term		9 years 8 months 12 days
Share-based compensation expense		$ 300	$ 200
Unrecognized compensation cost related to non-vested stock options		$ 300
Share-based compensation cost expected to recognize weighted-average term		1 year
Employee Stock Option [Member] \| Performance-based Stock Options [Member] \| Two Executives [Member]
Number of shares granted during the period	81,334
Stock options vesting period, description	The awards vest over 2 years if there is positive total shareholder return (e.g. share price increase) as measured to the 5-day (January 11-15, 2021) and (January 10-14, 2022) share price volume weighted average price ("VWAP").
Share-based compensation unvested shares of stock options		81,334
Restricted Stock [Member]
Share-based compensation expense		$ 15	$ 100
Unrecognized compensation cost related to non-vested stock options		$ 10
Share-based compensation cost expected to recognize weighted-average term		7 months 6 days
Restricted stock options, granted during period		13,513
2015 Omnibus Incentive Plan [Member]
Share-based compensation arrangement by share-based payment award, number of shares authorized				732,036	132,036		32,036	12,036
Termination period		10 years
Termination date		Oct. 31, 2025
Stock based compensation shares, available for grant		168,808
2018 Inducement Plan [Member]
Stock based compensation shares, available for grant		11,487				25,000

Share-Based Compensation Plans - Schedule of Share-based Payment Award, Stock Options, Valuation Assumptions (Details)	12 Months Ended
	Apr. 30, 2020	Apr. 30, 2019
Employee Stock Option [Member]
Risk-free interest rate	1.70%	2.70%
Expected dividend yield	0.00%	0.00%
Expected life (in years)		5 years 6 months
Expected volatility		126.40%
Employee Stock Option [Member] \| Minimum [Member]
Expected life (in years)	5 years 6 months
Expected volatility	127.60%
Employee Stock Option [Member] \| Maximum [Member]
Expected life (in years)	5 years 8 months 12 days
Expected volatility	128.20%
Performance Stock Option [Member]
Risk-free interest rate	2.30%
Expected dividend yield	0.00%
Expected life (in years)	10 years
Expected volatility	115.00%

Share-Based Compensation Plans - Schedule of Stock Option Activity (Details) - Stock Incentive Plan [Member]	12 Months Ended
	Apr. 30, 2020 $ / shares shares
Shares Underlying Options Outstanding, Beginning \| shares	65,572
Shares Underlying Options Outstanding, Granted \| shares	493,000
Shares Underlying Options Outstanding, Exercised \| shares
Shares Underlying Options Outstanding, Cancelled/forfeited \| shares	(3,097)
Shares Underlying Options Outstanding, Ending \| shares	555,475
Shares Underlying Options Outstanding, Exercisable at Ending \| shares	62,475
Weighted Average Exercise Price, Beginning Balance \| $ / shares	$ 21.08
Weighted Average Exercise Price, Granted \| $ / shares	1.05
Weighted Average Exercise Price, Exercised \| $ / shares
Weighted Average Exercise Price, Cancelled/forfeited \| $ / shares	44.32
Weighted Average Exercise Price, Ending Balance \| $ / shares	3.19
Weighted Average Exercise Price, Exercisable at Ending \| $ / shares	$ 20.09
Weighted Average Remaining Contractual Term (In Years), Beginning	8 years 10 months 25 days
Weighted Average Remaining Contractual Term (In Years), Ending	9 years 6 months
Weighted Average Remaining Contractual Term (In Years), Exercisable at Ending	7 years 10 months 25 days

Share-Based Compensation Plans - Schedule of Non-vested Restricted Stock Activity (Details)	12 Months Ended
	Apr. 30, 2020 $ / shares shares
Number of Shares, Granted	51,547
Non-vested Restricted Stock [Member]
Number of Shares, Issued and unvested, Beginning	4,506
Number of Shares, Granted	13,513
Number of Shares, Vested	(4,380)
Number of Shares, Cancelled/forfeited	(126)
Number of Shares, Issued and Unvested, Ending	13,513
Weighted Average Price per Share, Issued and Unvested, Beginning \| $ / shares	$ 30.08
Weighted Average Price per Share, Granted \| $ / shares	1.48
Weighted Average Price per Share, Vested \| $ / shares	30.14
Weighted Average Price per Share, Cancelled/forfeited \| $ / shares	28.00
Weighted Average Price per Share, Issued and Unvested, Ending \| $ / shares	$ 1.48

Fair Value Measurements - Schedule of Fair Value, Assets and Liabilities Measured on Recurring Basis (Details) - USD ($) $ in Thousands	Apr. 30, 2020	Apr. 30, 2019
Warrant liabilities		$ 6
Fair Value, Measurements, Recurring [Member]
Warrant liabilities		6
Fair Value, Measurements, Recurring [Member] \| Fair Value, Inputs, Level 1 [Member]
Warrant liabilities
Fair Value, Measurements, Recurring [Member] \| Fair Value, Inputs, Level 2 [Member]
Warrant liabilities
Fair Value, Measurements, Recurring [Member] \| Fair Value, Inputs, Level 3 [Member]
Warrant liabilities		$ 6

Fair Value Measurements - Summary of Changes on Value of Warrant Liability Using Significant Unobservable Inputs (Details) - Warrant Liability [Member] - USD ($) $ in Thousands	12 Months Ended
	Apr. 30, 2020	Apr. 30, 2019
Fair value, beginning	$ 6	$ 201
Change in fair value	(6)	(195)
Fair value, ending		$ 6

Income Taxes (Details Narrative) - USD ($) $ in Thousands	12 Months Ended
Income Taxes (Details Narrative) - USD ($) $ in Thousands	Apr. 30, 2020	Apr. 30, 2019
Income tax benefits	$ (895)	$ (850)
Deferred tax assets, valuation allowance	42,431	41,708
Increase (decrease) in valuation allowance	700	(2,500)
Net operating loss carry forwards	$ 160,700	152,500
Operating loss carryforwards, expiration description	Begin to expire in fiscal 2021
Net operating loss subject to no expiration	$ 22,600
Operating loss carryforwards, deductibility limitation	The deductibility of such federal net operating losses may be limited to 80% of our taxable income in future years.
Deferred tax assets, tax credit carryforwards, research and development	$ 3,076	3,315
Operating loss carryforwards, limitation on use	The Company's annual Section 382 limitation is approximately $3.3 million. The Section 382 limitation is cumulative from year to year, and thus, to the extent net operating loss or other credit carry forwards are not utilized up to the amount of the available annual limitation, the limitation is carried forward and added to the following year's available limitation. Such limitation only applies to net operating losses incurred in periods prior to the ownership change. The Company has not performed additional analysis on ownership changes that may have occurred subsequently to further limit the ability to utilize net tax attributes.
Proceed from sale of loss carryforwards and tax credits	$ 10,000	9,100
Income tax description	Net operating loss and credit carry forwards since inception remain open to examination by taxing authorities and will continue to remain open for a period of time after utilization.
Uncertain tax positions
Spain [Member]
Income tax description	The Company is currently undergoing an income tax audit in Spain for the period from 2011 to 2014
Uncertain tax positions
Interest or penalties accrued on uncertain tax positions
State and Local Jurisdiction [Member]
Net operating loss carry forwards	$ 22,500	$ 23,300
Operating loss carryforwards, expiration description	Begin to expire in 2039, which also may be limited to utilization limitations.	Begin to expire in 2039, which also may be limited to utilization limitations.
Foreign [Member]
Net operating loss carry forwards	$ 16,300	$ 16,900

Income Taxes - Schedule of Components of Loss Before Income Taxes (Details) - USD ($) $ in Thousands	12 Months Ended
	Apr. 30, 2020	Apr. 30, 2019
Income Tax Disclosure [Abstract]
Domestic	$ (10,985)	$ (12,860)
Foreign	(262)	(236)
Total loss before income taxes	$ (11,247)	$ (13,096)

- Definition

Amount of income (loss) from continuing operations, including income (loss) from equity method investments, before deduction of income tax expense (benefit), and income (loss) attributable to noncontrolling interest.

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+ Details

Income Taxes - Schedule of Effective Income Tax Rate Reconciliation (Details)	12 Months Ended
	Apr. 30, 2020	Apr. 30, 2019
Income Tax Disclosure [Abstract]
Computed expected tax (benefit)	(21.00%)	(21.00%)
State income taxes, net of federal (benefit)	2.90%	0.80%
Federal research and development tax credits	(0.50%)	(1.50%)
Foreign rate differential	5.20%	0.20%
Other non-deductible expenses	0.00%	0.10%
Proceeds of sale of New Jersey tax (benefits)	8.00%	(6.50%)
Other	5.20%	0.60%
Increase in valuation allowance	8.30%	20.80%
Income tax (benefit)	(7.90%)	(6.50%)

Income Taxes - Schedule of Deferred Tax Assets and Liabilities (Details) - USD ($) $ in Thousands	Apr. 30, 2020	Apr. 30, 2019
Income Tax Disclosure [Abstract]
Federal net operating loss carryforwards	$ 33,740	$ 32,025
Foreign net operating loss carryforwards	3,307	3,641
State operating loss carryforwards	1,598	1,653
Federal and New Jersey research and development tax credits	3,076	3,315
Stock compensation	311	486
Accrued expenses	131	145
Other	595	443
Net deferred tax assets before valuation allowance	42,758	41,708
Valuation allowance	(42,431)	(41,708)
Deferred tax assets	327
Lease liability	327
Net deferred tax assets

Commitments and Contingencies (Details Narrative) - USD ($)	Mar. 03, 2020	Aug. 28, 2018	Apr. 30, 2020	Apr. 30, 2019
Share price per share	$ 1.00
Nasdaq delisting notification description	The Company received a notification from the NASDAQ Stock Market (the "NASDAQ") indicating that the minimum bid price of the Company's common stock has been below $1.00 per share for 30 consecutive business days and as a result, the Company is not in compliance with the minimum bid price requirement for continued listing. The NASDAQ notice has no immediate effect on the listing or trading of the Company's common stock. Under the NASDAQ Listing Rules, the Company has a grace period of 180 calendar days, or until August 31, 2020, in which to regain compliance with the minimum bid price rule. To regain compliance, the closing bid price of the Company's common stock must meet or exceed $1.00 per share for a minimum of ten consecutive business days during this grace period. On April 20, 2020, the Company received a written notice from NASDAQ indicating that, as a result of the tolling of the bid price requirements due to COVID-19, the period within which the Company has to regain compliance was extended from August 31, 2020 to November 13, 2020.
Selling, General and Administrative [Member] \| Tax Authority, Spain [Member]
Income tax examination, penalties and interest accrued			$ 177,000	$ 177,000
Charles F. Dunleavy [Member]
Damages sought value		$ 5,000,000

Operating Segments and Geographic Information (Details Narrative)	12 Months Ended
	Apr. 30, 2020 segments
Segment Reporting [Abstract]
Number of reportable segments	1

Operating Segments and Geographic Information - Schedule of Revenue from External Customers and Long-Lived Assets, by Geographical Areas (Details) - USD ($) $ in Thousands	12 Months Ended
	Apr. 30, 2020	Apr. 30, 2019
Revenues from external customers	$ 1,682	$ 632
Operating loss	(11,365)	(13,271)
Long-lived assets	499	592
Total assets	13,538	18,366
North America [Member]
Revenues from external customers	1,682	632
Operating loss	(11,110)	(13,045)
Long-lived assets	499	592
Total assets	13,251	18,028
Europe [Member]
Revenues from external customers
Operating loss	(234)	(204)
Long-lived assets
Total assets	36	49
Asia and Australia [Member]
Revenues from external customers
Operating loss	(21)	(22)
Long-lived assets
Total assets	$ 251	$ 289

- Definition

Sum of the carrying amounts as of the balance sheet date of all assets that are recognized. Assets are probable future economic benefits obtained or controlled by an entity as a result of past transactions or events.

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- Definition

Amount, excluding tax collected from customer, of revenue from satisfaction of performance obligation by transferring promised good or service to customer. Tax collected from customer is tax assessed by governmental authority that is both imposed on and concurrent with specific revenue-producing transaction, including, but not limited to, sales, use, value added and excise.

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+ Details

Subsequent Event (Details Narrative) - Subsequent Event [Member] - Paycheck Protection Program [Member] - Loan Agreement [Member] - USD ($)	May 05, 2020	May 03, 2020
Debt amount		$ 890,347
Debt forgiveness, description	The SBA allows loan forgiveness for costs incurred and paid for a) payroll costs, b) interest on any real or personal property mortgage incurred prior to February 15, 2020, c) rent on any lease in force prior to February 15, 2020, and d) utility payments for which service began before February 15, 2020.