0001493152-22-006755 | 10-Q | XBRL Viewer | Ocean Power Technologies INC

Revenue Benchmark [Member] | Customer Concentration Risk [Member] | Eni S.p.A [Member]

$ 484

$ 317

$ 1,003

$ 604

Revenue Benchmark [Member] | Customer Concentration Risk [Member] | Department of Energy [Member]

135

Revenue Benchmark [Member] | Customer Concentration Risk [Member] | EGP [Member]

102

182

Revenue Benchmark [Member] | Customer Concentration Risk [Member] | ACET [Member]

223

163

379

Revenue Benchmark [Member] | Customer Concentration Risk [Member] | Valaris FNI [Member]

Revenue Benchmark [Member] | Customer Concentration Risk [Member] | Brigham Young University [Member]

^[1]

142

Revenue Benchmark [Member] | Customer Concentration Risk [Member] | Nippon Kaiyo [Member]

Revenue Benchmark [Member] | Customer Concentration Risk [Member] | Naval Surface Warfare Center [Member]

^[2]

Revenue Benchmark [Member] | Customer Concentration Risk [Member] | Other [Member]

^[2]

Operating Segments and Geographic Information

$ 133

$ 27

$ 260

$ 53

[1]	3Dent related consulting
[2]	MAR related sales

Commitments and Contingencies (Details Narrative)	May 24, 2021 USD ($)	Aug. 28, 2018 USD ($)	Jan. 31, 2021 USD ($)	Jan. 31, 2021 EUR (€)	Jan. 25, 2021 EUR (€)
Selling, General and Administrative Expenses [Member] \| Tax Authority, Spain [Member]
Loss Contingencies [Line Items]
Income tax penalties			$ 331,000	€ 279,870	€ 279,870
Charles F. Dunleavy [Member]
Loss Contingencies [Line Items]
Loss contingency, damages sought, value	$ 1,223,963.14	$ 438,254.54

Operating Segments and Geographic Information

9 Months Ended

Jan. 31, 2022

Segment Reporting [Abstract]

(17) Operating Segments and Geographic Information

The Company’s business consists of one segment as this represents how our Chief Operating Decision Maker views the Company’s operations and financial position. The Company operates on a worldwide basis with two wholly-owned subsidiaries, 3Dent and MAR, and subsidiaries in the UK and in Australia. Revenues and expenses are generally attributed to the operating company that bills the customers. During each of the nine months ended January 31, 2022 and 2021, the Company’s primary business operations were in North America.

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.

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

Schedule of Cash and Cash Equivalents (Details) - USD ($) $ in Thousands	Jan. 31, 2022	Apr. 30, 2021
Cash and Cash Equivalents [Line Items]
Cash and cash equivalents	$ 63,454	$ 83,028
Checking and Savings Accounts [Member]
Cash and Cash Equivalents [Line Items]
Cash and cash equivalents	1,519	1,850
Money Market Funds [Member]
Cash and Cash Equivalents [Line Items]
Cash and cash equivalents	$ 61,935	$ 81,178

Fair Value Measurements (Tables)

9 Months Ended

Jan. 31, 2022

Fair Value Disclosures [Abstract]

	January 31, 2022		January 31, 2021

Dividend rate		N/A		0.0	%
Risk-free rate		N/A - N/A		0.07% - 0.08%
Expected life (years)		N/A		0.5 - 0.8
Expected volatility		N/A		146.1	%

Account Receivable and Contract Assets

9 Months Ended

Jan. 31, 2022

Account Receivable And Contract Assets

Account Receivable and Contract Assets

(3) Account Receivable and Contract Assets

The following provides further details on the balance sheet accounts of accounts receivable and contract assets from contracts with customers:

	January 31, 2022		April 30, 2021
	(in thousands)
Accounts receivable	$	113	$	350
Contract assets		407		190
Contract liabilities		15		—

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 goods have transferred to the customer. Accounts receivable represent an unconditional right to consideration arising from the Company’s performance under contracts with customers. The carrying value of such receivables represents their estimated realizable value.

Contract Assets

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. Significant changes in the contract assets balance during the period were as follows:

	Nine months ended January 31, 2022
	(in thousands)
Transferred to receivables from contract assets recognized at the beginning of the period	$	(190	)
Revenue recognized and not billed as of the end of the period		407
Net change in contract assets	$	217

Property and Equipment, net (Details Narrative) - USD ($) $ in Thousands	9 Months Ended
	Jan. 31, 2022	Jan. 31, 2021
Property, Plant and Equipment [Abstract]
Depreciation expense	$ 104,000	$ 106,000

Consolidated Statements of Comprehensive Loss (Unaudited) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Jan. 31, 2022	Jan. 31, 2021	Jan. 31, 2022	Jan. 31, 2021
Income Statement [Abstract]
Net loss	$ (5,471)	$ (3,151)	$ (13,721)	$ (9,560)
Foreign currency translation adjustment	(1)	(2)	(14)	6
Total comprehensive loss	$ (5,472)	$ (3,153)	$ (13,735)	$ (9,554)

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

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

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Share-based Compensation Arrangement by Share-based Payment Award [Line Items]

Share-Based Compensation (Tables)

9 Months Ended

Jan. 31, 2022

Schedule of Valuation Assumptions

	Nine months ended January 31,
	2022			2021
Risk-free interest rate		1.5	%		6.0	%
Expected dividend yield		—	%		—	%
Expected life (in years)		5.6			5.9
Expected volatility		121.9	%		136.5	%

Schedule of Stock Option Activity

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

Schedule of Stock Option Activity

	Shares Underlying Options			Weighted Average Exercise Price		Weighted Average Remaining Contractual Term (In Years)
Outstanding as of April 30, 2021		516,827		$	3.89		9.0
Granted		793,850		$	1.43
Exercised		(44,332	)	$	1.05
Expired		(1,806	)	$	32.62
Cancelled/forfeited		(121,383	)	$	3.03
Outstanding as of January 31, 2022		1,143,156		$	2.34		9.4
Exercisable as of January 31, 2022		308,481		$	4.59		8.1

Schedule of Business Acquisition and Fair Value of Net Assets, Compensation Expense Recognized

Fair Value of Purchase	$	1,161,267
Total Acquired Assets	$	(593,571	)
Total Acquired Liabilities	$	117,106
Compensation Expense	$	684,802
Quarterly Compensation Expense	$	171,201

Schedule of Non-vested Restricted Stock Activity

A summary of non-vested restricted stock under our stock incentive plans is as follows:

	Number of Shares			Weighted Average Price per Share
Issued and unvested at April 30, 2021		10,000		$	2.93
Granted		777,764		$	1.42
Vested		(10,000	)	$	2.93
Cancelled/forfeited		—		$	—
Issued and unvested at January 31, 2022		777,764		$	1.42

Performance Stock Options [Member]

Share-based Compensation Arrangement by Share-based Payment Award [Line Items]

Schedule of Stock Option Activity

	Shares Underlying Options			Weighted Average Exercise Price		Weighted Average Remaining Contractual Term (In Years)
Outstanding as of April 30, 2021		424,790		$	2.57		9.5
Granted		66,667		$	0.62
Exercised		(40,668	)	$	1.05
Cancelled/forfeited		(220,766	)	$	2.58
Outstanding as of January 31, 2022		230,023		$	2.26		9.1
Exercisable as of January 31, 2022		—					0.0

Preferred Stock (Details Narrative) - $ / shares	Jan. 31, 2022	Apr. 30, 2021
Equity [Abstract]
Preferred stock, shares authorized	5,000,000	5,000,000
Preferred stock, par value	$ 0.001	$ 0.001
Preferred stock, shares issued	0	0

Summary of Significant Accounting Policies (Policies)

9 Months Ended

Jan. 31, 2022

Accounting Policies [Abstract]

Consolidation

(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.

Use of Estimates

(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 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, among other items, valuations, purchase price allocations and contingent consideration related to business combinations, expected future cash flows including growth rates, discount rates, terminal values and other assumptions and estimates used to evaluate the recoverability of long-lived assets, goodwill and other intangible assets and the related amortization methods and periods, estimated costs to complete projects and percentage of completion of customer contracts for purposes of revenue recognition. Actual results could differ from those estimates.

Cash, Cash Equivalents, Restricted Cash and Security Agreements

(c) Cash, 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 as of January 31, 2022 and April 30, 2021:

Schedule of Cash and Cash Equivalents

	January 31, 2022		April 30, 2021
	(in thousands)

Checking and savings accounts	$	1,519	$	1,850
Money market account		61,935		81,178
	$	63,454	$	83,028

Restricted Cash and Security Agreements

The Company has a letter of credit agreement with Santander Bank, N.A. (“Santander”). Cash of $157,000 is on deposit at Santander and serves as security for a letter of credit issued by Santander for the lease of warehouse/office space in Monroe Township, New Jersey. This agreement cannot be extended beyond July 31, 2025 and is cancellable at the discretion of Santander.

Santander also issued two letters of credit to subsidiaries of Enel Green Power (“EGP”) pursuant to the Company’s contracts with EGP. The first letter of credit was issued in the amount of $126,000 that will be released 12 months after the PB3 PowerBuoy^®(“PB3”) is fully deployed. The second letter of credit was issued in the amount of $645,000 and was reduced to $323,000 in August 2020. The second letter of credit will be reduced by $259,000 once the PB3 is fully deployed and passes final acceptance testing. The remaining restricted amount of $64,000 will be released 12 months after the buoy is fully deployed.

The following table provides a reconciliation of cash, cash equivalents and restricted cash reported within the Consolidated Balance Sheets that total to the same amounts shown in the Consolidated Statements of Cash Flows.

	January 31, 2022		April 30, 2021
	(in thousands)
Cash and cash equivalents	$	63,454	$	83,028
Restricted cash- short term		384		384
Restricted cash- long term		222		222
	$	64,060	$	83,634

Concentration of Credit Risk

(d) Concentration of Credit Risk

Financial instruments that potentially subject the Company to credit risk consist principally of accounts receivable and cash and cash equivalents. The Company believes that its current contracts do not represent a risk of collectability on its receivables. The Company invests its excess cash in a money market account and does not believe that it is exposed to any significant risks related to its cash and money market accounts. Cash and cash equivalents are also maintained at foreign financial institutions. Cash and cash equivalents in foreign financial institutions as of January 31, 2022 was $30,000.

The table below shows the amount 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:

	2022		2021		2022		2021
	Three months ended January 31,				Nine months ended January 31,
	2022		2021		2022		2021
	(in thousands)				(in thousands)
Eni S.p.A.	$	—	$	34	$	14	$	135
Department of Energy		102		—		182		—
EGP		—		223		163		379
ACET		—		33		—		37
Valaris (1)		7		—		142		—
Brigham Young University (2)		66		—		66		—
Nippon Kaiyo (2)		78		—		78		—
Naval Surface Warfare Center (2)		98		—		98		—
Other (no customer over 10%)		133		27		260		53
Revenues	$	484	$	317	$	1,003	$	604

(1)	3Dent related consulting
(2)	MAR related sales

Share-Based Compensation

(e) Share-Based Compensation

Costs resulting from all share-based payment transactions are recognized in the consolidated financial statements at their fair values. The following table summarizes share-based compensation related to the Company’s share-based plans by expense category for the three and nine months ended January 31, 2022 and 2021:

	2022		2021		2022		2021
	Three months ended January 31,				Nine months ended January 31,
	2022		2021		2022		2021
	(in thousands)				(in thousands)
Engineering and product development	$	209	$	32	$	551	$	91
Selling, general and administrative		108		83		313		247
Total share-based compensation expense	$	317	$	115	$	864	$	338

Revenue Recognition

(f) 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 consideration, 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. There was no variable consideration as of January 31, 2022 or 2021. The Company presents 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 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. 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. If estimated total costs on any contract project a loss, the Company charges the entire estimated loss to operations in the period the loss becomes known. The cumulative effect of revisions to revenue, estimated costs to complete contracts, including penalties, incentive awards, change orders, claims, anticipated losses, and others are recorded in the accounting period in which the events indicating a loss are known and the loss can be reasonably estimated. These loss projects are re-assessed for each subsequent reporting period until the project is complete. Such revisions could occur at any time and the effects may be material.

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, and 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 nine-month periods ended January 31, 2022 and 2021, all of the Company’s contracts were classified as firm fixed price.

As of January 31, 2022, the Company’s total remaining performance obligations, also referred to as backlog, totaled $0.8 million. The Company expects to recognize 100% of the remaining performance obligations as revenue over the next twelve months.

The Company also enters into lease arrangements for its PB3 and our Wave Adaptive Modular Vessels (“WAM-V”) with certain customers. 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.

Products and Solutions Leasing

The Company enters into lease arrangements with certain customers for their products and solutions. As of January 31, 2022, the Company had one lease arrangement with a remaining operating lease term of less than 7 months. 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 other leases are treated as operating leases.

The Company recognizes revenue from operating lease arrangements generally on a straight-line basis over the lease term which is presented in Revenues in the Consolidated Statements of Operations. The lease revenue for the nine months ended January 31, 2022 and 2021 was immaterial.

Net Loss per Common Share

(g) Net Loss per Common Share

Basic and diluted net loss per common 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 periods. 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 basic net loss per common share . 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 net loss per common share calculation due to their anti-dilutive effect.

In computing diluted net loss per common share on the Consolidated Statements of Operations, warrants exercisable for common stock, options to purchase shares of common stock and non-vested restricted stock issued to employees and non-employee directors, totaling 6,356,123 and 5,221,258 for the nine months ended January 31, 2022 and 2021, respectively, were excluded from each of the computations as the effect would be anti-dilutive due to the Company’s net losses.

Recently Issued Accounting Standards

(h) Recently Issued Accounting Standards

In June 2016, the Financial Accounting Standards Board (“FASB”) issued ASU No. 2016-13, “Financial Instruments - Credit Losses (Topic 326), Measurement of Credit Losses on Financial Instruments.” This amendment 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. In November 2019, the FASB issued No. 2019-10, Financial Instruments—Credit Losses (Topic 326), Derivatives and Hedging (Topic 815), and Leases (Topic 842), which deferred the effective date of ASU 2016-13 for Smaller Reporting Companies for fiscal years beginning after December 15, 2022, including interim periods within those fiscal years. The Company is currently evaluating the impact of the adoption of ASU 2016-13 on its consolidated financial statements.

Disclosure of accounting policy for revenue from contract with customer.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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Income Taxes

9 Months Ended

Jan. 31, 2022

Income Tax Disclosure [Abstract]

Income Taxes

(16) Income Taxes

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. At January 31, 2022, the Company had no 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.

Income Tax Benefit

The Company sold New Jersey State net operating losses and research development credits under the NJEDA Tax Transfer program in the amount of approximately $12.0 million for the year ended April 30, 2021, for net proceeds of approximately $1.0 million which was received in May 2021 and recorded in the Company’s Statement of Operations in fiscal year 2022. This results from a program where New Jersey-based technology or biotechnology companies with fewer than 225 US employees may be eligible to sell net operating losses and research and development tax credits to unaffiliated corporations, up to a maximum lifetime benefit of $20.0 million per business. As of January 31, 2022 we have approximately $5.0 million still available to sell should we chose to do so.

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.

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Summary of Significant Accounting Policies

Schedule of Significant Changes in Contract Assets and Contract Liabilities (Details) - USD ($) $ in Thousands	9 Months Ended
	Jan. 31, 2022	Jan. 31, 2021
Account Receivable And Contract Assets
Transferred to receivables from contract assets recognized at the beginning of the period	$ (190)
Revenue recognized and not billed as of the end of the period	407
Net change in contract assets	$ 217	$ (188)

Background, Basis of Presentation and Liquidity (Details Narrative) - USD ($) $ / shares in Units, $ in Thousands									3 Months Ended		9 Months Ended		12 Months Ended
	Jan. 31, 2022	Jul. 31, 2021	Dec. 23, 2020	Nov. 20, 2020	Sep. 18, 2020	Oct. 24, 2019	Apr. 08, 2019	Jan. 07, 2019	Jan. 31, 2022	Jan. 31, 2021	Jan. 31, 2022	Jan. 31, 2021	Apr. 30, 2021	Oct. 31, 2021	Jul. 01, 2019
Net loss									$ 5,471	$ 3,151	$ 13,721	$ 9,560	$ 14,800
Net cash in operating activities											15,787	8,525	$ 11,700
Cash	$ 63,500								$ 63,500		63,500
Proceeds from initial public offering												$ 66,166
Number of common stock shares sold							1,542,000	12,342,506
Proceeds from issuance or sale of equity, net of issuance costs								$ 18,700
Combined purchase price per share															$ 1.51
Deferred Offering Costs				$ 100,000
2019 ATM Facility [Member]
Proceeds from initial public offering								$ 25,000
Number of common stock shares sold								17,595,472
Proceeds from issuance or sale of equity, net of issuance costs								$ 23,400
Combined purchase price per share								$ 1.33
Payment of sales commission								$ 800
2020 ATM Facility [Member]
Number of common stock shares sold											17,179,883
Proceeds from issuance or sale of equity, net of issuance costs											$ 75,000
Combined purchase price per share	$ 2.91								$ 2.91		$ 2.91
Payment of sales commission											$ 25,000
Proceeds from initial public offering				$ 50,000
Stock Purchase Agreement [Member]
Number of common stock shares sold		3,722,251			6,424,205
Proceeds from issuance or sale of equity, net of issuance costs	$ 1,000	$ 11,800			$ 4,000
Combined purchase price per share					$ 0.63									$ 3.17
Aggregate purchase of common stock					$ 12,500
Percentage of outstanding common stock			19.99%		19.99%
Shares can be issued based upon outstanding percentage					3,722,251
Additional sales of common stock shares sold			9,864,706
Stock Purchase Agreement [Member] \| Maximum [Member]
Aggregate purchase of common stock						$ 10,000
Stock Purchase Agreement One [Member]
Number of common stock shares sold													5,025,000
Proceeds from issuance or sale of equity, net of issuance costs													$ 2,900
Combined purchase price per share													$ 0.57

Treasury Shares

9 Months Ended

Jan. 31, 2022

Equity [Abstract]

Treasury Shares

(12) Treasury Shares

During each of the nine months ended January 31, 2022 and 2021, no shares of common stock were purchased by the Company from employees to pay taxes related to the vesting of restricted stock.

Schedule of Stock Option Activity (Details) - $ / shares	9 Months Ended
	Jan. 31, 2022
Stock Incentive Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares Underlying Options Outstanding, Beginning	516,827
Weighted Average Exercise Price, Beginning Balance	$ 3.89
Weighted Average Remaining Contractual Term (In Years), Beginning	9 years
Shares Underlying Options Outstanding, Granted	793,850
Weighted Average Exercise Price, Granted	$ 1.43
Shares Underlying Options Outstanding, Exercised	(44,332)
Weighted Average Exercise Price, Exercised	$ 1.05
Shares Underlying Options Outstanding, Expired	(1,806)
Weighted Average Exercise Price, Expired	$ 32.62
Shares Underlying Options Outstanding, Cancelled/forfeited	(121,383)
Weighted Average Exercise Price, Cancelled/forfeited	$ 3.03
Shares Underlying Options Outstanding, Ending	1,143,156
Weighted Average Exercise Price, Ending Balance	$ 2.34
Weighted Average Remaining Contractual Term (In Years), Ending	9 years 4 months 24 days
Shares Underlying Options Outstanding, Exercisable at Ending	308,481
Weighted Average Exercise Price, Exercisable at Ending	$ 4.59
Weighted Average Remaining Contractual Term (In Years), Exercisable at Ending	8 years 1 month 6 days
Performance Stock Options [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares Underlying Options Outstanding, Beginning	424,790
Weighted Average Exercise Price, Beginning Balance	$ 2.57
Weighted Average Remaining Contractual Term (In Years), Beginning	9 years 6 months
Shares Underlying Options Outstanding, Granted	66,667
Weighted Average Exercise Price, Granted	$ 0.62
Shares Underlying Options Outstanding, Exercised	(40,668)
Weighted Average Exercise Price, Exercised	$ 1.05
Shares Underlying Options Outstanding, Cancelled/forfeited	(220,766)
Weighted Average Exercise Price, Cancelled/forfeited	$ 2.58
Shares Underlying Options Outstanding, Ending	230,023
Weighted Average Exercise Price, Ending Balance	$ 2.26
Weighted Average Remaining Contractual Term (In Years), Ending	9 years 1 month 6 days
Shares Underlying Options Outstanding, Exercisable at Ending
Weighted Average Remaining Contractual Term (In Years), Exercisable at Ending	0 years

Summary of Significant Accounting Policies

9 Months Ended

Jan. 31, 2022

Accounting Policies [Abstract]

(2) Summary of Significant Accounting Policies

(a) Consolidation

(b) Use of Estimates

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

Cash and Cash Equivalents

Schedule of Cash and Cash Equivalents

	January 31, 2022		April 30, 2021
	(in thousands)

Checking and savings accounts	$	1,519	$	1,850
Money market account		61,935		81,178
	$	63,454	$	83,028

Restricted Cash and Security Agreements

	January 31, 2022		April 30, 2021
	(in thousands)
Cash and cash equivalents	$	63,454	$	83,028
Restricted cash- short term		384		384
Restricted cash- long term		222		222
	$	64,060	$	83,634

(d) Concentration of Credit Risk

	2022		2021		2022		2021
	Three months ended January 31,				Nine months ended January 31,
	2022		2021		2022		2021
	(in thousands)				(in thousands)
Eni S.p.A.	$	—	$	34	$	14	$	135
Department of Energy		102		—		182		—
EGP		—		223		163		379
ACET		—		33		—		37
Valaris (1)		7		—		142		—
Brigham Young University (2)		66		—		66		—
Nippon Kaiyo (2)		78		—		78		—
Naval Surface Warfare Center (2)		98		—		98		—
Other (no customer over 10%)		133		27		260		53
Revenues	$	484	$	317	$	1,003	$	604

(1)	3Dent related consulting
(2)	MAR related sales

(e) Share-Based Compensation

	2022		2021		2022		2021
	Three months ended January 31,				Nine months ended January 31,
	2022		2021		2022		2021
	(in thousands)				(in thousands)
Engineering and product development	$	209	$	32	$	551	$	91
Selling, general and administrative		108		83		313		247
Total share-based compensation expense	$	317	$	115	$	864	$	338

(f) Revenue Recognition

Products and Solutions Leasing

(g) Net Loss per Common Share

(h) Recently Issued Accounting Standards

Business Combination

9 Months Ended

Jan. 31, 2022

Business Combination and Asset Acquisition [Abstract]

Business Combination

(18) Business Combination

3dent Technologies, LLC

On February 1, 2021, the Company acquired all of the outstanding equity interest of 3dent Technologies, LLC (“3Dent”), a Houston, Texas based company that offers offshore energy engineering and design services that are complementary to the Company’s technology and products. As consideration for the purchase, the Company issued 361,991 shares of its common stock to the sellers, subject to a 12-month post acquisition employment condition, which has now been achieved. In addition, the former owners of 3Dent would have been eligible for awards of performance stock with a potential value of $360,000 if certain revenue targets are achieved over the 12 month-period post acquisition. As of January 31, 2022, it was determined that 3Dent did not meet these revenue targets.

Marine Advance Robotics, Inc.

On November 15, 2021, the Company acquired all of the outstanding equity interest of Marine Advanced Robotics, Inc. (“MAR”), a Richmond (San Francisco Bay Area), California-based developer and manufacturer of autonomous surface vehicles.

The Company accounted for the transaction as a business combination under ASC 805, “Business Combinations.” Accordingly, the assets and liabilities acquired were recorded at their estimated fair value on the date of acquisition. Under ASC 805, acquisition-related transaction costs of approximately $0.3 million (such as advisory, legal, valuation, other professional fees) were expensed in the Consolidated Statement of Operations in the period incurred.

The Company paid cash consideration of $4.0 million and issued 3,330,162 shares of our common stock valued at approximately $5.9 million based on the closing price of $2.10 and reduced by a lack of marketability discount since they were restricted. The Company assumed liability for advances payable to the former owners of MAR for approximately $456,000.

The contingent consideration is based on the achievement of certain milestones over a 30-month period. As of the acquisition date, the contingent consideration had a fair value of $1.6 million. Under the terms of the MAR purchase agreement, the contingent consideration consists of two earn-out periods, one running from the date of the acquisition through April 30, 2023 in which the maximum earn-out is $1.5 million and the other from May 1, 2023 through April 30, 2024 where the maximum earn-out is $2 million. The fair value as of the date of acquisition was determined using a simulation model based on an estimate of revenues during these periods and discount factors ranging from 5.8% to 14.5%. As discussed in Note 14 per ASC Topic 820 we consider this to be a Level 3 liability.

Total consideration including cash, restricted shares, liabilities assumed, and contingent consideration was valued at approximately $11.9 million.

Purchase consideration consisted of the following:

Schedule of Purchase Consideration

	(in thousands)
Cash	$	4,000
Liabilities assumed		456
Fair value of restricted shares		5,855
Fair value of contingent consideration		1,591
Total consideration	$	11,902

The preliminary allocation of the fair value of the MAR acquisition is shown in the table below. The allocation of the fair value will be finalized when the valuation is completed, and the differences will be trued up for the final allocated amounts, hence, actual results may differ from preliminary estimate.

Total Purchase Consideration	$	11,902

Cash	$	12
Inventory		150
Property and equipment, net		38
Trademarks		2,755
Patents		1,193
Goodwill		7,754
Net assets acquired	$	11,902

The net assets were recorded at their estimated fair value. In valuing acquired assets and liabilities, fair value estimates were based primarily on future expected cash flows, market rate assumptions, and appropriate discount rates. In connection with the acquisition of MAR, we acquired approximately $3.9 million of intangible assets including trademarks with an indefinite life and patents that will be amortized over a useful life of nine years.

Goodwill is considered an indefinite-lived asset that relates primarily to intangible assets that do not qualify for separate recognition. The Company is currently evaluating the tax implications on the business combination accounting and compiling the information needed for a pro forma disclosure related to the acquisition of MAR which is expected in our year end reporting.

Warrants (Details Narrative) - $ / shares	Apr. 08, 2019	Jan. 07, 2019	Jul. 22, 2016	Jun. 02, 2016
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Number of common stock shares sold	1,542,000	12,342,506
Pre-funded Warrants [Member]
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Purchase of warrants	3,385,680
Exercise price of warrants	$ 0.01
Common Warrants [Member]
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Purchase of warrants	4,927,680
Exercise price of warrants	$ 3.85
Warrants and rights outstanding, term	5 years
June Purchase Agreement [Member]
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Number of common stock shares sold				20,850
Purchase of warrants				7,298
Purchase of common stock warrants				0.35
Common stock combined purchase price per share				$ 92.00
Exercise price of warrants				$ 121.60
Warrants and rights outstanding, term				5 years
Number of exercised warrants				0
Second Amended Purchase Agreement [Member]
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Number of common stock shares sold			29,750
Purchase of warrants			8,925
Purchase of common stock warrants			0.30
Common stock combined purchase price per share			$ 135.00
Exercise price of warrants			$ 187.20
Warrants and rights outstanding, term			5 years
Number of exercised warrants			0
Warrants and Rights Outstanding, Maturity Date			Jan. 23, 2022

Property and Equipment, net (Tables)

9 Months Ended

Jan. 31, 2022

Property, Plant and Equipment [Abstract]

Schedule of Components of Property and Equipment

The components of property and equipment, net as of January 31, 2022 and April 30, 2021 consisted of the following:

	January 31, 2022			April 30, 2021
	(in thousands)
Equipment	$	320		$	291
Computer equipment & software		521			498
Office furniture & equipment		352			341
Leasehold improvements		474			474
Construction in process		15			15
Property and equipment, gross		1,682			1,619
Less: accumulated depreciation		(1,317	)		(1,213	)
Property and equipment, net	$	365		$	406

Schedule of Right-of Use Assets and Lease Liabilities (Details) - USD ($) $ in Thousands	Jan. 31, 2022	Apr. 30, 2021
Leases
Operating right-of-use asset, net	$ 825	$ 1,036
Right-of-use liability- current	323	347
Right-of-use liability- long term	615	$ 819
Total lease liability	$ 938
Weighted average remaining lease term- operating leases	2 years 7 months 9 days
Weighted average discount rate- operating leases	8.20%

Accrued Expenses

9 Months Ended

Jan. 31, 2022

Payables and Accruals [Abstract]

Accrued Expenses

(7) Accrued Expenses

Accrued expenses consisted of the following at January 31, 2022 and April 30, 2021:

Schedule of Accrued Expenses

	January 31, 2022		April 30, 2021
	(in thousands)		(in thousands)
Project costs	$	102	$	368
Contract loss reserve		328		328
Employee incentive payments		191		283
Accrued salary and benefits		409		631
Professional fees		96		200
Other		166		71
Accrued expenses total	$	1,292	$	1,881

Preferred Stock

9 Months Ended

Jan. 31, 2022

Equity [Abstract]

Preferred Stock

(10) 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 January 31, 2022, no shares of preferred stock had been issued.

Summary of Significant Accounting Policies (Tables)

9 Months Ended

Jan. 31, 2022

Accounting Policies [Abstract]

Schedule of Cash and Cash Equivalents

	January 31, 2022		April 30, 2021
	(in thousands)

Checking and savings accounts	$	1,519	$	1,850
Money market account		61,935		81,178
	$	63,454	$	83,028

Schedule of Cash and Cash Equivalents and Restricted Cash

	January 31, 2022		April 30, 2021
	(in thousands)
Cash and cash equivalents	$	63,454	$	83,028
Restricted cash- short term		384		384
Restricted cash- long term		222		222
	$	64,060	$	83,634

Schedule of Revenue by Major Customers by Reporting Segments

	2022		2021		2022		2021
	Three months ended January 31,				Nine months ended January 31,
	2022		2021		2022		2021
	(in thousands)				(in thousands)
Eni S.p.A.	$	—	$	34	$	14	$	135
Department of Energy		102		—		182		—
EGP		—		223		163		379
ACET		—		33		—		37
Valaris (1)		7		—		142		—
Brigham Young University (2)		66		—		66		—
Nippon Kaiyo (2)		78		—		78		—
Naval Surface Warfare Center (2)		98		—		98		—
Other (no customer over 10%)		133		27		260		53
Revenues	$	484	$	317	$	1,003	$	604

(1)	3Dent related consulting
(2)	MAR related sales

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

	2022		2021		2022		2021
	Three months ended January 31,				Nine months ended January 31,
	2022		2021		2022		2021
	(in thousands)				(in thousands)
Engineering and product development	$	209	$	32	$	551	$	91
Selling, general and administrative		108		83		313		247
Total share-based compensation expense	$	317	$	115	$	864	$	338

Property and Equipment, net

9 Months Ended

Jan. 31, 2022

Property, Plant and Equipment [Abstract]

Property and Equipment, net

(5) Property and Equipment, net

The components of property and equipment, net as of January 31, 2022 and April 30, 2021 consisted of the following:

	January 31, 2022			April 30, 2021
	(in thousands)
Equipment	$	320		$	291
Computer equipment & software		521			498
Office furniture & equipment		352			341
Leasehold improvements		474			474
Construction in process		15			15
Property and equipment, gross		1,682			1,619
Less: accumulated depreciation		(1,317	)		(1,213	)
Property and equipment, net	$	365		$	406

Depreciation expense was approximately $104,000 and $106,000 for the nine month periods ended January 31, 2022 and 2021, respectively.

Leases

9 Months Ended

Jan. 31, 2022

Leases

Leases

(6) Leases

Lessor Information

As of January 31, 2022, 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 term on this operating lease is less than 7 months. The maturity of lease payments remaining on this lease is immaterial.

Lessee Information

The Company has a 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 seven years which expires in November of 2024 with an option to extend the lease for another five 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 also has two leases for properties located in Houston, Texas. The first was acquired as part of the 3Dent acquisition (see Note 18) that is used as office space. The lease term is for 3 years and is set to expire in January of 2023. The lease is classified as an operating lease and included in the right-of-use assets, lease liabilities- current and lease liabilities- long-term on the Company’s Consolidated Balance Sheets.

The other Houston lease is for additional office space and was renewed for a 12-month term ending on June 30, 2022. In accordance with ASC 842-20-5-2, since the lease term at the time of renewal was 12 months, the asset was recognized directly to the profit and loss statement on a straight-line basis and was not recognized as a right-of-use asset.

The Company also has a lease with the University of California Berkeley in Berkeley, California that was acquired as part of the MAR acquisition (see Note 18). The lease expires on June 30, 2022. In accordance with ASC 842-20-5-2, since the remaining lease term at the time of the acquisition of MAR was less than 12 months, the asset was recognized directly to the profit and loss statement on a straight-line basis and was not recognized as a right-of-use asset.

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 commencement date. When the implicit rate of the lease is not provided or cannot be determined, the Company uses 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 cash flow payments for the three months ended January 31, 2022 and 2021 were $111,000 and $91,000, respectively. The operating lease cash flow payments for the nine months ended January 31, 2022 and 2021 were $315,000 and $259,000, respectively.

The components of lease expense in the Consolidated Statements of Operations for the three and nine months ended January 31, 2022 and 2021 were as follows:

Schedule of Operating Lease Costs

	2022		2021		2022		2021
	Three months ended January 31,				Nine months ended January 31,
	2022		2021		2022		2021
	(in thousands)				(in thousands)
Operating lease cost	$	92	$	79	$	276	$	238
Short-term lease cost		12		7		22		12
Total lease cost	$	104	$	86	$	298	$	250

Information related to the Company’s right-of use assets and lease liabilities as of January 31, 2022 was as follows:

	January 31, 2022
		(in thousands)

Operating lease:
Operating right-of-use asset, net	$	825

Right-of-use liability- current	$	323
Right-of-use liability- long term		615
Total lease liability	$	938

Weighted average remaining lease term- operating leases		2.61 years
Weighted average discount rate- operating leases		8.2	%

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

	January 31, 2022
	(in thousands)

Remainder of fiscal year 2022	$	99
2023		391
2024		362
2025		184
Total future minimum lease payments	$	1,036
Less imputed interest		(98	)
Total	$	938

Consolidated Balance Sheets - USD ($) $ in Thousands	Jan. 31, 2022	Apr. 30, 2021
Current assets:
Cash and cash equivalents	$ 63,454	$ 83,028
Restricted cash, short-term	384	384
Accounts receivable	113	350
Contract assets	407	190
Inventory	193
Other current assets	436	487
Total current assets	64,987	84,439
Property and equipment, net	365	406
Intangibles, net	4,203	274
Right-of-use asset, net	825	1,036
Restricted cash, long-term	222	222
Goodwill	7,754
Total assets	78,356	86,377
Current liabilities:
Accounts payable	522	687
Accrued expenses	1,292	1,881
Contract liabilities	15
Right-of-use liability, current portion	323	347
Advance payable	456
Litigation payable		1,224
Contingent liabilities	1,591	60
Paycheck protection program loan- current		495
Total current liabilities	4,199	4,694
Paycheck protection program loan, less current portion		396
Right-of-use liability, less current portion	615	819
Total liabilities	4,814	5,909
Commitments and contingencies (Note 15)
Shareholders’ 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 55,894,213 and 52,458,011 shares, respectively	56	52
Treasury stock, at cost; 21,040 shares	(338)	(338)
Additional paid-in capital	322,626	315,821
Accumulated deficit	(248,617)	(234,896)
Accumulated other comprehensive loss	(185)	(171)
Total shareholders’ equity	73,542	80,468
Total liabilities and shareholders’ equity	$ 78,356	$ 86,377

Schedule of Accrued Expenses (Details) - USD ($) $ in Thousands	Jan. 31, 2022	Apr. 30, 2021
Payables and Accruals [Abstract]
Project costs	$ 102	$ 368
Contract loss reserve	328	328
Employee incentive payments	191	283
Accrued salary and benefits	409	631
Professional fees	96	200
Other	166	71
Accrued expenses total	$ 1,292	$ 1,881

Paycheck Protection Program Loan (Details Narrative) - Paycheck Protection Program [Member] - USD ($)		9 Months Ended
	May 03, 2020	Oct. 31, 2021
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Proceeds from loan originations	$ 890,000
Debt forgiveness, description	The Company filed its loan forgiveness application at the end of February 2021 asking for 100% forgiveness of the loan. In June 2021, the Company was informed that its application was approved, and that the loan is now fully forgiven. The Company recognized a gain on extinguishment of PPP loan of approximately $890,000 during the nine months ended October 31, 2021 as reflected on the Consolidated Statement of Operations.
Debt interest rate	100.00%
Repayments of long-term debt		$ 890,000

Schedule of Business Acquisition and Fair Value of Net Assets, Compensation Expense Recognized (Details) - 3Dent Acquisition [Member]	Feb. 01, 2021 USD ($)
Restructuring Cost and Reserve [Line Items]
Fair Value of Purchase	$ 1,161,267
Total Acquired Assets	(593,571)
Total Acquired Liabilities	117,106
Compensation Expense	684,802
Quarterly Compensation Expense	$ 171,201

Fair Value Measurements (Details Narrative) - USD ($)	Jan. 31, 2022	Apr. 30, 2021
Fair Value Disclosures [Abstract]
Fair value on a recurring basis	$ 0	$ 0

Consolidated Balance Sheets (Parenthetical) - $ / shares	Jan. 31, 2022	Apr. 30, 2021
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	0	0
Preferred stock, shares outstanding	0	0
Common stock, par value	$ 0.001	$ 0.001
Common stock, shares authorized	100,000,000	100,000,000
Common stock, shares issued	55,894,213	52,458,011
Treasury stock, shares	21,040	21,040

Subsequent Events (Details Narrative) - USD ($) $ in Thousands	1 Months Ended	3 Months Ended		9 Months Ended
	Feb. 28, 2022	Jan. 31, 2022	Jan. 31, 2021	Jan. 31, 2022	Jan. 31, 2021
Subsequent Event [Line Items]
Income Tax Expense (Benefit)				$ (1,041)
Subsequent Event [Member] \| New Jersey Division of Taxation [Member]
Subsequent Event [Line Items]
Operating Loss Carryforwards	$ 4,000
Income Tax Expense (Benefit)	$ 400

Amount of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations.

+ References + Details

Consolidated Statements of Operations (Unaudited) - USD ($) shares in Thousands, $ in Thousands	3 Months Ended		9 Months Ended
	Jan. 31, 2022	Jan. 31, 2021	Jan. 31, 2022	Jan. 31, 2021
Income Statement [Abstract]
Revenues	$ 484	$ 317	$ 1,003	$ 604
Cost of revenues	597	698	1,320	1,248
Gross loss	(113)	(381)	(317)	(644)
Operating expenses:
Engineering and product development costs	2,465	1,019	7,518	3,334
Selling, general and administrative costs	2,974	1,763	7,933	5,591
Total operating expenses	5,439	2,782	15,451	8,925
Operating loss	(5,552)	(3,163)	(15,768)	(9,569)
Interest income, net	16	25	56	45
Other income (expense), net	60	(16)	60	(49)
Gain on extinguishment of PPP loan			890
Foreign exchange gain	5	3		13
Loss before income taxes	(5,471)	(3,151)	(14,762)	(9,560)
Income tax benefit			1,041
Net loss	$ (5,471)	$ (3,151)	$ (13,721)	$ (9,560)
Basic and diluted net loss per common share	$ (0.10)	$ (0.09)	$ (0.26)	$ (0.41)
Weighted average common shares used to compute basic and diluted net loss per common share	55,308,799	33,715,334	53,408,998	23,160,885

Common Stock

9 Months Ended

Jan. 31, 2022

Equity [Abstract]

Common Stock

(11) Common Stock

The Company has authorized 100,000,000 shares of common stock with a par value of $0.001 per share. As of January 31, 2022, 55,894,213 shares had been issued and are outstanding.

The entire disclosure for shareholders' equity comprised of portions attributable to the parent entity and noncontrolling interest, including other comprehensive income. Includes, but is not limited to, balances of common stock, preferred stock, additional paid-in capital, other capital and retained earnings, accumulated balance for each classification of other comprehensive income and amount of comprehensive income.

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Share-based Payment Arrangement [Abstract]

Summary of Significant Accounting Policies (Details Narrative) - USD ($)	9 Months Ended
	Jan. 31, 2022	Jan. 31, 2021	Apr. 30, 2021	Aug. 31, 2020
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Cash and Cash Equivalents, at Carrying Value	$ 63,454,000		$ 83,028,000
Revenue remaining performance obligation	$ 800,000
Revenue remaining performance obligation, percentage	100.00%
Antidilutive securities excluded from computation of earnings per share, amount	6,356,123	5,221,258
Santander Bank [Member]
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Letters of credit issued amount	$ 64,000
Santander Bank [Member] \| Letter 2 [Member]
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Letters of credit issued amount	259,000
Santander Bank [Member] \| Letter 2 [Member] \| August 2020 [Member]
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Letters of Credit Outstanding, Amount				$ 323,000
Foreign Financial Institutions [Member]
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Cash and Cash Equivalents, at Carrying Value	30,000
Restricted Cash and Security Agreements [Member] \| Santander Bank [Member] \| Letter of Credit [Member]
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Deposits	157,000
Restricted Cash and Security Agreements [Member] \| Santander Bank [Member] \| Letter 1 [Member]
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Letters of Credit Outstanding, Amount	126,000
Restricted Cash and Security Agreements [Member] \| Santander Bank [Member] \| Letter 2 [Member]
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Letters of Credit Outstanding, Amount	$ 645,000

Share-Based Compensation

9 Months Ended

Jan. 31, 2022

Share-Based Compensation

(13) Share-Based Compensation

In 2015, upon approval by the Company’s shareholders, the Company’s 2015 Omnibus Incentive Plan (the “2015 Plan”) became effective. A total of 1,332,036 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. 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 January 31, 2022, the Company has 696,627 shares available for future issuance under the 2015 Plan which reflects adjustments made for the departure of our former CEO as well as other departures.

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 711(a) of the NYSE American Company Guide, awards under the Inducement Plan may only be made to individuals not previously employed by 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 January 31, 2022, there were 11,487 shares available for grant under the 2018 Inducement Plan. On February 9, 2022 the 2018 Inducement Plan was amended to increase the authorized shares by 250,000 to 275,000.

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 is estimated using the “simplified” method as permitted by the SEC’s Staff Accounting Bulletin No. 110, Share-Based Payment. Expected volatility is based on the Company’s historical volatility over the expected life of the stock option granted. The Company granted options to acquire 793,850 and 248,876 shares of stock options during the three and nine months ended January 31, 2022 and 2021, respectively. The following assumptions were used to value the awards:

Schedule of Valuation Assumptions

	Nine months ended January 31,
	2022			2021
Risk-free interest rate		1.5	%		6.0	%
Expected dividend yield		—	%		—	%
Expected life (in years)		5.6			5.9
Expected volatility		121.9	%		136.5	%

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

Schedule of Stock Option Activity

	Shares Underlying Options			Weighted Average Exercise Price		Weighted Average Remaining Contractual Term (In Years)
Outstanding as of April 30, 2021		516,827		$	3.89		9.0
Granted		793,850		$	1.43
Exercised		(44,332	)	$	1.05
Expired		(1,806	)	$	32.62
Cancelled/forfeited		(121,383	)	$	3.03
Outstanding as of January 31, 2022		1,143,156		$	2.34		9.4
Exercisable as of January 31, 2022		308,481		$	4.59		8.1

As of January 31, 2022, the total intrinsic value of outstanding and exercisable options was approximately $11,560. As of January 31, 2022, approximately 835,000 additional options were unvested, which had an intrinsic value of zero and a weighted average remaining contractual term of 9.9 years. There was approximately $183,000 and $296,000 of total recognized compensation cost related to stock options during each of the nine months ended January 31, 2022 and 2021, respectively. As of January 31, 2022, there was approximately $102,000 of total unrecognized compensation cost related to non-vested stock options granted under the plans. This cost is expected to be recognized over a weighted-average period of 1.0 year.

The Company’s acquisition of 3Dent (See Note 18) was valued at the fair value of the stock on the acquisition date of $1,451,584 (361,991 shares at $4.01). Since the share restrictions were set to expire on February 1, 2022, within one year of the closing of the acquisition, and lacked marketability, the Company applied a 20% discount to the purchase price making the adjusted fair value $1,161,267. Additionally, as the sellers must be employed for 12 months from the date of acquisition to retain all of their shares, the difference between the calculated fair value and the net assets acquired represents the value of the compensation expense to be recognized over the period of the agreed upon employment.

Fair Value of Purchase	$	1,161,267
Total Acquired Assets	$	(593,571	)
Total Acquired Liabilities	$	117,106
Compensation Expense	$	684,802
Quarterly Compensation Expense	$	171,201

The Company has recognized approximately $171,000 of compensation expense on a quarterly basis for the consideration paid for 12 months from the acquisition date of February 2, 2021. The last of this compensation expense was recognized during the quarter ended January 31, 2022.

Performance Stock Options

In January 2020, the Company issued 81,337 performance-based stock options to two of its executives. There were 40,668 shares that were vested and outstanding, which were set to expire on December 15, 2021, all of which were exercised prior to the expiration date.

In January 2021, the Company issued 344,723 performance-based stock options to employees and executives. The awards vest over 2 years provided there is positive total shareholder return (e.g. share price increase) as measured by the closing share price on January 14, 2022 and January 14, 2023. There were 230,000 shares unvested and outstanding at January 31, 2022. None of the shares granted to our former President and CEO under this issuance vested prior to June 18, 2021, his last day of employment. These unvested shares are included in the Cancelled/forfeited figure in the table below. A summary of performance stock options under our stock incentive plans is detailed in the following table.

Schedule of Stock Option Activity

	Shares Underlying Options			Weighted Average Exercise Price		Weighted Average Remaining Contractual Term (In Years)
Outstanding as of April 30, 2021		424,790		$	2.57		9.5
Granted		66,667		$	0.62
Exercised		(40,668	)	$	1.05
Cancelled/forfeited		(220,766	)	$	2.58
Outstanding as of January 31, 2022		230,023		$	2.26		9.1
Exercisable as of January 31, 2022		—					0.0

As of January 31, 2022, the total intrinsic value of both outstanding and exercisable options was approximately zero. As of January 31, 2022, approximately 230,000 options were unvested, which had an intrinsic value of zero and a weighted average remaining contractual term of 9.1 years. There was approximately $123,000 and $43,000 of total recognized compensation cost related to stock options during each of the nine months ended January 31, 2022 and 2021, respectively. As of January 31, 2022, there was approximately $242,000 of total unrecognized compensation cost related to non-vested stock options granted under the plans. This cost is expected to be recognized over a weighted-average period of 1.1 years.

Restricted Stock

Compensation expense for non-vested 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 nine months ended January 31, 2022 and 2021, the Company granted 777,764 and 10,000 shares, respectively, that were subject to service-based vesting requirements.

A summary of non-vested restricted stock under our stock incentive plans is as follows:

	Number of Shares			Weighted Average Price per Share
Issued and unvested at April 30, 2021		10,000		$	2.93
Granted		777,764		$	1.42
Vested		(10,000	)	$	2.93
Cancelled/forfeited		—		$	—
Issued and unvested at January 31, 2022		777,764		$	1.42

There was approximately $43,000 and $12,000 of total recognized compensation cost related to restricted stock for the nine months ended January 31, 2022 and 2021, respectively. As of January 31, 2022, there is approximately $54,000 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 approximately 1.4 years.

In December 2019, the Company granted 51,547 shares to an employee, subject to service-based vesting requirements, that were outside the Company stock incentive plans. There was approximately zero and $30,000 of total recognized compensation cost related to this award for the three months ended January 31, 2022 and 2021, respectively. As of January 31, 2022, there was no unrecognized compensation cost remaining related to this award.

Accrued Expenses (Tables)

9 Months Ended

Jan. 31, 2022

Payables and Accruals [Abstract]

Schedule of Accrued Expenses

Accrued expenses consisted of the following at January 31, 2022 and April 30, 2021:

Schedule of Accrued Expenses

	January 31, 2022		April 30, 2021
	(in thousands)		(in thousands)
Project costs	$	102	$	368
Contract loss reserve		328		328
Employee incentive payments		191		283
Accrued salary and benefits		409		631
Professional fees		96		200
Other		166		71
Accrued expenses total	$	1,292	$	1,881

Schedule of Cash and Cash Equivalents and Restricted Cash (Details) - USD ($) $ in Thousands	Jan. 31, 2022	Apr. 30, 2021
Accounting Policies [Abstract]
Cash and cash equivalents	$ 63,454	$ 83,028
Restricted cash- short term	384	384
Restricted cash- long term	222	222
Cash, cash equivalents and restricted cash	$ 64,060	$ 83,634

Business Combination (Details Narrative) - USD ($)			3 Months Ended	9 Months Ended
Business Combination (Details Narrative) - USD ($)	Nov. 15, 2021	Feb. 01, 2021	Jan. 31, 2022	Jan. 31, 2022
Business Acquisition [Line Items]
Stock Issued During Period, Value, Acquisitions			$ 5,855,000	$ 5,855,000
Acquisition related costs				$ 300,000
3Dent Acquisition [Member]
Business Acquisition [Line Items]
Stock Issued During Period, Shares, Acquisitions		361,991
Stock Issued During Period, Value, Acquisitions		$ 360,000
Business Acquisition, Share Price		$ 4.01
Marine Advanced Robotics, Inc. [Member]
Business Acquisition [Line Items]
Payments to Acquire Businesses, Gross	$ 4,000,000
Business Combination, Contingent Consideration, Asset	$ 1,591,000
Business combination, description	the contingent consideration consists of two earn-out periods, one running from the date of the acquisition through April 30, 2023 in which the maximum earn-out is $1.5 million and the other from May 1, 2023 through April 30, 2024 where the maximum earn-out is $2 million. The fair value as of the date of acquisition was determined using a simulation model based on an estimate of revenues during these periods and discount factors ranging from 5.8% to 14.5%.
Business Combination, Consideration Transferred	$ 11,902,000
Business acquistion intangible assets	$ 3,900,000
Marine Advanced Robotics, Inc. [Member] \| Restricted Stock [Member]
Business Acquisition [Line Items]
Business Acquisition, Equity Interest Issued or Issuable, Number of Shares	3,330,162
Business Acquisition, Equity Interest Issued or Issuable, Value Assigned	$ 5,900,000
Business Acquisition, Share Price	$ 2.10

Schedule of Accounts Receivable, Contract Assets and Contract Liabilities (Details) - USD ($) $ in Thousands	Jan. 31, 2022	Apr. 30, 2021
Account Receivable And Contract Assets
Accounts receivable	$ 113	$ 350
Contract assets	407	190
Contract liabilities	$ 15

Schedule of Operating Lease Costs (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Jan. 31, 2022	Jan. 31, 2021	Jan. 31, 2022	Jan. 31, 2021
Leases
Operating lease cost	$ 92	$ 79	$ 276	$ 238
Short-term lease cost	12	7	22	12
Total lease cost	$ 104	$ 86	$ 298	$ 250

Fair Value Measurements

9 Months Ended

Jan. 31, 2022

Fair Value Disclosures [Abstract]

Fair Value Measurements

(14) Fair Value Measurements

ASC Topic 820, “Fair Value Measurements” states that fair value is an exit price, representing the amount 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. Assets and liabilities that are measured at fair value are reported using a three-level fair value hierarchy that prioritizes the inputs used to measure fair value. This hierarchy maximizes the use of observable input and minimizes the use of unobservable inputs. The following is a description of the three hierarchy levels.

Level 1	Unadjusted quoted prices in active markets for identical assets or liabilities that the Company has the ability to access at the measurement date.

Level 2	Inputs other than quoted prices in active markets that are observable for the asset or liability, either directly or indirectly.

Level 3	Inputs that are unobservable for the asset or liability.

Disclosure of Fair Values

The Company’s financial instruments that are not re-measured at fair value include cash, cash equivalents, restricted cash, accounts receivable, contract assets and liabilities, deposits, accounts payable, and accrued expenses. The carrying values of these financial instruments approximate their fair values and are viewed as Level 1 items. The Company’s warrant liabilities represent the only asset or liability classified financial instrument that is measured at fair value on a recurring basis.

The fair value of the Company’s warrant liabilities (refer to Note 8) is based on the Black-Scholes pricing model which is based on Level 3 unobservable inputs for which there is little or no market data, requiring the Company to develop its own assumptions. The assumptions used by the Company are the quoted price of the Company’s common stock in an active market, risk-free interest rate, volatility and expected life, and assumes no dividends. 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 fair value on a recurring basis as of January 31, 2022 and April 30, 2021 was near zero.

There were no unrealized gains or losses for the three and nine months ended January 31, 2022 or 2021. When incurred, gains and losses are included within “Gain (loss) due to change in fair value of warrant liabilities” in the Consolidated Statements of Operations. The Company determined the fair value using the Black-Scholes pricing model with the following assumptions:

	January 31, 2022		January 31, 2021

Dividend rate		N/A		0.0	%
Risk-free rate		N/A - N/A		0.07% - 0.08%
Expected life (years)		N/A		0.5 - 0.8
Expected volatility		N/A		146.1	%

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 hierarchy levels during each of the three and nine months ended January 31, 2022 or 2021.

Commitments and Contingencies Disclosure [Abstract]

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

Common Stock (Details Narrative) - $ / shares	Jan. 31, 2022	Apr. 30, 2021
Equity [Abstract]
Common stock, shares authorized	100,000,000	100,000,000
Common stock, par value	$ 0.001	$ 0.001
Common stock, shares issued	55,894,213	52,458,011
Common stock, shares outstanding	55,894,213

Commitments and Contingencies

9 Months Ended

Jan. 31, 2022

Commitments and Contingencies

(15) Commitments and Contingencies

Employment Litigation

On August 28, 2018, counsel for Charles Dunleavy, the Company’s former President & Chief Executive Officer who was terminated for cause effective June 9, 2014, 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 alleged various claims relating to Mr. Dunleavy’s termination. After the hearings in the proceeding were conducted, on December 11, 2020, the arbitration panel issued an interim award finding, among other things, that the termination for cause of Mr. Dunleavy was in breach of his employment contract and awarded him compensatory damages in the amount of $438,254.54. On May 3, 2021, the panel issued a second interim award and therein awarded Mr. Dunleavy attorneys’ fees, costs and pre-judgment interest. The Company agreed, on May 24, 2021, to pay Mr. Dunleavy $1,223,963.14, representing the total compensatory damages, attorneys’ fees, costs and pre-judgment interest, which is the full amount awarded by the arbitration panel. The Company made the required payment on May 26, 2021, and the matter is now closed.

Spain Income Tax Audit

The Company underwent an income tax audit in Spain for the period from 2011 to 2014, when our Spanish branch was closed. On July 30, 2018, the Spanish tax inspector concluded that although there was no tax owed in light of losses reported, the Company’s Spanish branch owed penalties for failure to properly account for the income associated with the funding grant. During the nine months ended January 31, 2021, the Company received notice from the Spanish Central Economic and Administrative Tribunal that it agreed with the inspector and ruled that the Company owes the full amount of the penalty in the amount of €279,870 or approximately $331,000. On January 25, 2021, the Company paid the Spanish Tax Administration €279,870. Notwithstanding that payment, on April 30, 2021, the Company filed its appeal of the decision of the Central Court to the Spanish National Court. There is no schedule for a ruling from the Spanish National Court.

Schedule of Other Current Assets (Details) - USD ($) $ in Thousands	Jan. 31, 2022	Apr. 30, 2021
Deferred Costs, Capitalized, Prepaid, and Other Assets Disclosure [Abstract]
Prepaid insurance	$ 178	$ 194
Prepaid software & licenses	84	93
Prepaid sales and marketing	65	37
Prepaid recruiting	57	12
Other receivables	24	21
Deposits		68
Prepaid expenses- other	28	62
Other current assets	$ 436	$ 487

Warrants

9 Months Ended

Jan. 31, 2022

Warrants

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 expired on December 3, 2021, five years following the Initial Exercise Date. As of the expiration date, none of the warrants had 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 expired on January 23, 2022, the fifth (5th) anniversary of the initial exercise date of January 23, 2017. As of the expiration date, none of the warrants had 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 January 31, 2022, all of the pre-funded warrants had 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 January 31, 2022, all of the common warrants had been exercised.

The Company accounts for warrants issued in connection with its June 2016 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 2016 and July 2016 warrants contained 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 were all expired as of January 31, 2022 and had a value near zero as of April 30, 2021. 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 shareholders’ equity in the Consolidated Balance Sheets.

Schedule of Employee Service Share-based Compensation, Allocation of Recognized Period Costs (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Jan. 31, 2022	Jan. 31, 2021	Jan. 31, 2022	Jan. 31, 2021
Total share-based compensation expense	$ 317	$ 115	$ 864	$ 338
Engineering and Product Development [Member]
Total share-based compensation expense	209	32	551	91
Selling, General and Administrative Expenses [Member]
Total share-based compensation expense	$ 108	$ 83	$ 313	$ 247

Other Current Assets (Tables)

9 Months Ended

Jan. 31, 2022

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

Schedule of Other Current Assets

Other current assets consisted of the following at January 31, 2022 and April 30, 2021:

Schedule of Other Current Assets

	January 31, 2022		April 30, 2021
	(in thousands)
Prepaid insurance	$	178	$	194
Prepaid software & licenses		84		93
Prepaid sales and marketing		65		37
Prepaid recruiting		57		12
Other receivables		24		21
Deposits		—		68
Prepaid expenses- other		28		62
Other current assets	$	436	$	487

Schedule of Non-vested Restricted Stock Activity (Details) - Non-vested Restricted Stock [Member] - $ / shares	9 Months Ended
	Jan. 31, 2022	Jan. 31, 2021
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of Shares, Issued and unvested, Beginning	10,000
Weighted Average Price per Share, Issued and Unvested, Beginning	$ 2.93
Number of Shares, Granted	777,764	10,000
Weighted Average Price per Share, Granted	$ 1.42
Number of Shares, Vested	(10,000)
Weighted Average Price per Share, Vested	$ 2.93
Number of Shares, Cancelled/forfeited
Weighted Average Price per Share, Cancelled/forfeited
Number of Shares, Issued and Unvested, Ending	777,764
Weighted Average Price per Share, Issued and Unvested, Ending	$ 1.42

Business Combination (Tables)

9 Months Ended

Jan. 31, 2022

Business Combination and Asset Acquisition [Abstract]

Schedule of Purchase Consideration

Purchase consideration consisted of the following:

Schedule of Purchase Consideration

	(in thousands)
Cash	$	4,000
Liabilities assumed		456
Fair value of restricted shares		5,855
Fair value of contingent consideration		1,591
Total consideration	$	11,902

Schedule of Allocated Fair Value of Purchase Consideration

Total Purchase Consideration	$	11,902

Cash	$	12
Inventory		150
Property and equipment, net		38
Trademarks		2,755
Patents		1,193
Goodwill		7,754
Net assets acquired	$	11,902

Schedule of Share-based Payment Award, Stock Options, Valuation Assumptions (Details)	9 Months Ended
	Jan. 31, 2021
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Dividend rate	0.00%
Expected volatility	146.10%
Minimum [Member]
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Risk-free interest rate	0.07%
Expected life (in years)	6 months
Maximum [Member]
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Risk-free interest rate	0.08%
Expected life (in years)	9 months 18 days

Other Current Assets

9 Months Ended

Jan. 31, 2022

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

Other Current Assets

(4) Other Current Assets

Other current assets consisted of the following at January 31, 2022 and April 30, 2021:

Schedule of Other Current Assets

	January 31, 2022		April 30, 2021
	(in thousands)
Prepaid insurance	$	178	$	194
Prepaid software & licenses		84		93
Prepaid sales and marketing		65		37
Prepaid recruiting		57		12
Other receivables		24		21
Deposits		—		68
Prepaid expenses- other		28		62
Other current assets	$	436	$	487

Schedule of Allocated Fair Value of Purchase Consideration (Details) - USD ($) $ in Thousands	Nov. 15, 2021	Jan. 31, 2022
Business Acquisition [Line Items]
Goodwill		$ 7,754
Marine Advanced Robotics, Inc. [Member]
Business Acquisition [Line Items]
Total Purchase Consideration	$ 11,902
Intangible assets	3,900
Marine Advance Robotics Inc [Member]
Business Acquisition [Line Items]
Cash	12
Inventories	150
Property and equipment, net	38
Goodwill	7,754
Net assets acquired	11,902
Marine Advance Robotics Inc [Member] \| Patents [Member]
Business Acquisition [Line Items]
Intangible assets	1,193
Marine Advance Robotics Inc [Member] \| Trade Names [Member]
Business Acquisition [Line Items]
Intangible assets	$ 2,755

Leases (Tables)

9 Months Ended

Jan. 31, 2022

Leases

Schedule of Operating Lease Costs

The components of lease expense in the Consolidated Statements of Operations for the three and nine months ended January 31, 2022 and 2021 were as follows:

Schedule of Operating Lease Costs

	2022		2021		2022		2021
	Three months ended January 31,				Nine months ended January 31,
	2022		2021		2022		2021
	(in thousands)				(in thousands)
Operating lease cost	$	92	$	79	$	276	$	238
Short-term lease cost		12		7		22		12
Total lease cost	$	104	$	86	$	298	$	250

Schedule of Right-of Use Assets and Lease Liabilities

Information related to the Company’s right-of use assets and lease liabilities as of January 31, 2022 was as follows:

	January 31, 2022
		(in thousands)

Operating lease:
Operating right-of-use asset, net	$	825

Right-of-use liability- current	$	323
Right-of-use liability- long term		615
Total lease liability	$	938

Weighted average remaining lease term- operating leases		2.61 years
Weighted average discount rate- operating leases		8.2	%

Schedule of Future Minimum Lease Payments Under Operating Lease

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

	January 31, 2022
	(in thousands)

Remainder of fiscal year 2022	$	99
2023		391
2024		362
2025		184
Total future minimum lease payments	$	1,036
Less imputed interest		(98	)
Total	$	938

Schedule of Components of Property and Equipment (Details) - USD ($) $ in Thousands	Jan. 31, 2022	Apr. 30, 2021
Property, Plant and Equipment [Line Items]
Property and equipment, gross	$ 1,682	$ 1,619
Less: accumulated depreciation	(1,317)	(1,213)
Property and equipment, net	365	406
Equipment [Member]
Property, Plant and Equipment [Line Items]
Property and equipment, gross	320	291
Computer Equipment And Software [Member]
Property, Plant and Equipment [Line Items]
Property and equipment, gross	521	498
Office Furniture And Equipment [Member]
Property, Plant and Equipment [Line Items]
Property and equipment, gross	352	341
Leasehold Improvements [Member]
Property, Plant and Equipment [Line Items]
Property and equipment, gross	474	474
Construction in Progress [Member]
Property, Plant and Equipment [Line Items]
Property and equipment, gross	$ 15	$ 15

Leases (Details Narrative) - USD ($)	3 Months Ended		9 Months Ended
Leases (Details Narrative) - USD ($)	Jan. 31, 2022	Jan. 31, 2021	Jan. 31, 2022	Jan. 31, 2021
Operating lease payments	$ 111,000	$ 91,000	$ 315,000	$ 259,000
3Dent Acquisition [Member]
Lessee, operating lease, option to extend			expire in January of 2023
Lessee, operating lease, term of contract	3 years		3 years
Lease expiration date			Jun. 30, 2022
Monroe Township [Member]
Lessee, operating lease, option to extend			The initial lease term is for seven years which expires in November of 2024 with an option to extend the lease for another five years.
Lessee, operating lease, term of contract	7 years		7 years

Treasury Shares (Details Narrative) - shares	9 Months Ended
Treasury Shares (Details Narrative) - shares	Jan. 31, 2022	Jan. 31, 2021
Equity [Abstract]
Treasury stock, shares, acquired	0	0

Share-Based Compensation (Details Narrative) - USD ($)		1 Months Ended		3 Months Ended	9 Months Ended
Share-Based Compensation (Details Narrative) - USD ($)	Feb. 01, 2021	Jan. 31, 2021	Jan. 31, 2020	Jan. 31, 2022	Jan. 31, 2022	Jan. 31, 2021	Feb. 09, 2022	Feb. 08, 2022	Jan. 18, 2018	Dec. 31, 2015
3Dent Acquisition [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Fair value of base purchase price	$ 1,451,584
Stock Issued During Period, Shares, New Issues	361,991
Business Acquisition, Share Price	$ 4.01
Fair Value of Purchase	$ 1,161,267
Business comibination quarterly compensation expenses recognized consideration paid	$ 171,000
Share-based Payment Arrangement, Option [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based compensation options, grants in period, gross				793,850		248,876
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Intrinsic Value				$ 11,560	$ 11,560
Options unvested				835,000	835,000
Share-based Compensation Arrangement by Share-based Payment Award, Options, Vested and Expected to Vest, Exercisable, Weighted Average Remaining Contractual Term					9 years 10 months 24 days
Share-based payment arrangement, expense					$ 183,000	$ 296,000
Share-based Payment Arrangement, Option [Member] \| Employee [Member] \| Subject to Service- Based Vesting Requirements [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized compensation cost related to non-vested stock				$ 0	$ 0
Restricted stock option granted					51,547
Non-vested Stock [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized compensation cost related to non-vested stock				102,000	$ 102,000
Share-based compensation of weighted-average period					1 year
Performance Stock Options [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based compensation options, grants in period, gross					66,667
Shares vested and outstanding			40,668
Debt expire date			Dec. 15, 2021
Performance Stock Options [Member] \| Two Executives [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based compensation options, grants in period, gross			81,337
Performance Stock Options [Member] \| Employees and Executives [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based compensation options, grants in period, gross		344,723			230,000
Stock options vesting period description		The awards vest over 2 years provided there is positive total shareholder return (e.g. share price increase) as measured by the closing share price on January 14, 2022 and January 14, 2023.
Performance Shares [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Intrinsic Value				$ 0	$ 0
Options unvested				230,000	230,000
Share-based Compensation Arrangement by Share-based Payment Award, Options, Vested and Expected to Vest, Exercisable, Weighted Average Remaining Contractual Term					9 years 1 month 6 days
Share-based payment arrangement, expense					$ 123,000	$ 43,000
Unrecognized compensation cost related to non-vested stock				$ 242,000,000,000	$ 242,000,000,000
Share-based compensation of weighted-average period					1 year 1 month 6 days
Non-vested Restricted Stock [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Restricted stock option granted					777,764	10,000
Restricted Stock [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based payment arrangement, expense					$ 43,000	$ 12,000
Share-based compensation of weighted-average period					1 year 4 months 24 days
Unrecognized compensation cost				$ 54,000	$ 54,000
Equity Option [Member] \| Employee [Member] \| Subject to Service- Based Vesting Requirements [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based payment arrangement, expense					$ 0	$ 30,000
2015 Omnibus Incentive Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based compensation arrangement shares authorized										1,332,036
Capital shares reserved for future issuance				696,627	696,627
2018 Inducement Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based compensation arrangement shares authorized							275,000	250,000
Capital shares reserved for future issuance				11,487	11,487				25,000

Schedule of Valuation Assumptions (Details)	9 Months Ended
Schedule of Valuation Assumptions (Details)	Jan. 31, 2022	Jan. 31, 2021
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expected dividend yield		0.00%
Expected volatility		146.10%
Share-based Payment Arrangement, Option [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Risk-free interest rate	1.50%	6.00%
Expected dividend yield
Expected life (in years)	5 years 7 months 6 days	5 years 10 months 24 days
Expected volatility	121.90%	136.50%

Background, Basis of Presentation and Liquidity

9 Months Ended

Jan. 31, 2022

Organization, Consolidation and Presentation of Financial Statements [Abstract]

Background, Basis of Presentation and Liquidity

(1) Background, Basis of Presentation 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 and services. Our solutions provide distributed offshore power which is persistent, reliable, and economical along with power and communications for remote surface and subsea applications. Historically, funding from government agencies, such as research and development grants, accounted for a significant portion of the Company’s revenues. Today our goal is to generate the majority of our revenue from the sale or lease of our 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 products, solutions and services.

(b) Basis of Presentation

The accompanying unaudited consolidated financial statements have been prepared in accordance with accounting principles generally accepted in the United States of America (“GAAP”) and for interim financial information in accordance with the Securities and Exchange Commission (“SEC”), instructions to Form 10-Q and Article 10 of Regulation S-X. Accordingly, they do not include all the information and footnotes required by GAAP for complete financial statements. In the opinion of management, all adjustments (consisting of normal recurring adjustments) considered necessary for a fair presentation have been included. The interim operating results are not necessarily indicative of the results for a full year or for any other interim period. Further information on potential factors that could affect the Company’s financial results can be found in the Company’s Annual Report on Form 10-K for the year ended April 30, 2021, as filed with the SEC and elsewhere in this Form 10-Q. Certain items have been reclassified from prior periods to be consistent with current GAAP presentations.

(c) Liquidity

For the nine months ended January 31, 2022, and the fiscal year ended April 30, 2021, the Company incurred net losses of approximately $13.7 million and $14.8 million, respectively, and used cash in operating activities of approximately $15.8 million and $11.7 million, respectively. The Company has continued to make investments in ongoing product development efforts in anticipation of future growth, including its recent acquisition of Marine Advanced Robotics, Inc., as described in Note 18. The Company’s future results of operations involve significant risks and uncertainties. Factors that could affect the Company’s future operating results and could cause actual results to vary materially from expectations include, but are not limited to, performance of its products, its ability to market and commercialize its products and new products that it may develop, technology development, scalability of technology and production, ability to attract and retain key personnel, concentration of customers and suppliers, deployment risks and integration of acquisitions, pending or threatened litigation, and the impact of COVID-19, and any variants on its business. The Company previously obtained equity financing through its At the Market Offering Agreement (“ATM”) with A.G.P/Alliance Global Partners (“AGP”) and through its equity line financing with Aspire Capital Fund, LLC (“Aspire Capital”), 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. For fiscal year 2022 to date, management has not obtained any additional capital financing. Management believes the Company’s current cash balance of $63.5 million is sufficient to fund its planned expenditures through at least March 2023.

On January 7, 2019, the Company entered into an At the Market Offering Agreement with AGP (the “2019 ATM Facility”), under which the Company could 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 $25.0 million. From inception of the program through its termination on December 8, 2020, under the 2019 ATM Facility, the Company sold and issued an aggregate of 17,595,472 shares of its common stock with an aggregate market value of $23.4 million at an average price of $1.33 per share, including 12,342,506 shares in fiscal year 2021 with an aggregate market value of $18.7 million at an average price of $1.51 per share and paid AGP a sales commission of approximately $0.8 million related to those shares. The agreement was fully utilized and terminated on December 8, 2020.

On November 20, 2020, the Company entered into another At the Market Offering Agreement with AGP (the “2020 ATM Facility”), having capacity up to $100.0 million. On December 4, 2020, the Company filed a prospectus with the Securities and Exchange Commission whereby, the Company could 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 $50.0 million. From inception of the 2020 ATM Facility through January 31, 2022, the Company had sold and issued an aggregate of 17,179,883 shares of its common stock with an aggregate market value of $50.0 million at an average price of $2.91 per share and paid AGP a sales commission of approximately $1.6 million related to those shares. A prospectus supplement was filed on January 10, 2022 to allow the Company to sell an additional $25.0 million (or an aggregate of $75.0 million) under the 2020 ATM Facility, none of which has been sold to date.

Equity Line Common Stock Purchase Agreements

On October 24, 2019, 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 shares of the Company’s common stock over a 30-month period. Through September 18, 2020, the Company had sold an aggregate of 6,424,205 shares of common stock with an aggregate market value of $4.0 million at an average price of $0.63 per share pursuant to this common stock purchase agreement, including 5,025,000 shares in fiscal year 2021 with an aggregate market value of $2.9 million at an average price of $0.57 per share. The agreement was fully utilized and terminated on September 18, 2020.

On September 18, 2020, the Company entered into a new 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 $12.5 million shares of the Company’s common stock over a 30-month period subject to a limit of 19.99% of the outstanding common stock on the date of the agreement if the price did not exceed a specified price in the agreement. The number of shares the Company could issue within the 19.99% limit was 3,722,251 shares without shareholder approval. Shareholder approval was received at the Company’s annual meeting of shareholders on December 23, 2020 for the sale of 9,864,706 additional shares of common stock to Aspire Capital, which exceeded the 19.99% limit of the outstanding common stock on the date of the agreement. Through January 31, 2022, the Company had sold an aggregate of 3,722,251 shares of common stock with an aggregate market value of $11.8 million at an average price of $3.17 per share pursuant to this common stock purchase agreement with approximately $1.0 million remaining on the facility as of January 31, 2022.

Operating Segments and Geographic Information (Details Narrative)	9 Months Ended
	Jan. 31, 2022 Segment
Segment Reporting [Abstract]
Number of Operating Segments	1

Paycheck Protection Program Loan

9 Months Ended

Jan. 31, 2022

Debt Disclosure [Abstract]

Paycheck Protection Program Loan

(9) Paycheck Protection Program Loan

On March 27, 2020, the U.S. Government passed into law the Coronavirus Aid, Relief and Economic Security Act, or the (“CARES Act”). On May 3, 2020, the Company signed a Paycheck Protection Program (“PPP”) loan with Santander as the lender for approximately $890,000 in support through the Small Business Association (“SBA”) under the PPP Loan. The PPP Loan was unsecured and evidenced by a note in favor of Santander as the lender and governed by a Loan Agreement with Santander. The Company received the proceeds on May 5, 2020.

The Company filed its loan forgiveness application at the end of February 2021 asking for 100% forgiveness of the loan. In June 2021, the Company was informed that its application was approved, and that the loan is now fully forgiven. The Company recognized a gain on extinguishment of PPP loan of approximately $890,000 during the nine months ended October 31, 2021 as reflected on the Consolidated Statement of Operations.

The entire disclosure for information about short-term and long-term debt arrangements, which includes amounts of borrowings under each line of credit, note payable, commercial paper issue, bonds indenture, debenture issue, own-share lending arrangements and any other contractual agreement to repay funds, and about the underlying arrangements, rationale for a classification as long-term, including repayment terms, interest rates, collateral provided, restrictions on use of assets and activities, whether or not in compliance with debt covenants, and other matters important to users of the financial statements, such as the effects of refinancing and noncompliance with debt covenants.

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