Commitments and Contingencies	6 Months Ended
Oct. 31, 2020
Commitments and Contingencies Disclosure [Abstract]
Commitments and Contingencies	(16) Commitments and Contingencies Employment Litigation On June 10, 2014, the Company announced that it had terminated Charles Dunleavy as its Chief Executive Officer and as an employee of the Company for cause, effective June 9, 2014, and that Mr. Dunleavy had also been removed from his position as Chairman of the Board of Directors. On June 17, 2014, Mr. Dunleavy wrote to the Company stating that he had retained counsel to represent him in connection with an alleged wrongful termination of his employment. On July 28, 2014, Mr. Dunleavy resigned from the Board and the boards of directors of the Company’s subsidiaries. On August 28, 2018, counsel for Mr. Dunleavy filed a demand for arbitration, captioned Charles F. Dunleavy v. Ocean Power Technologies, Inc., Case No. 01-18-0003-2374, before the American Arbitration Association in New Jersey. The demand names Ocean Power Technologies, Inc. as the respondent and alleges various claims and seeks declaratory relief and permanent injunction. The demand seeks damages in the amount of $5 million for compensatory and punitive damages, plus interest and attorneys’ fees as well as certain equitable relief. On November 8, 2018, the Company through counsel responded to the demand for arbitration, denied all allegations, and asserted various affirmative defenses. The final day of hearing occurred in Princeton, New Jersey on July 15, 2020. Post-hearing briefs were filed on September 22, 2020. As of October 31, 2020, the Company has not accrued any provision related to this matter as we believe a loss is not probable and any possible loss cannot be reasonably estimated. Nasdaq Delisting Notification On March 3, 2020, the Company received a notification from the Nasdaq indicating that the minimum bid price of the Company’s common stock has been below $1.00 per share for 30 consecutive business days and as a result, the Company is not in compliance with the minimum bid price requirement for continued listing. The Nasdaq notice has no immediate effect on the listing or trading of the Company’s common stock. Under the Nasdaq Listing Rules, the Company has a grace period of 180 calendar days, or until August 31, 2020, in which to regain compliance with the minimum bid price rule. To regain compliance, the closing bid price of the Company’s common stock must meet or exceed $1.00 per share for a minimum of ten consecutive business days during this grace period. On August 21, 2020, the Company received notification from Nasdaq that, as a result of the closing bid price of the Company’s common stock being over $1.00 for 10 consecutive trading days, the Company has regained compliance with Listing Rule 5550(a)(2) to maintain the listing of its common stock on Nasdaq and Nasdaq considers the matter 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. In connection with the tax audit, the Spanish tax inspector challenged the Company’s recognition of grant funds received in 2011 to 2014 from the European Commission in connection with the Company’s Waveport project. On July 30, 2018, the 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. On August 30, 2018, the Company filed an administrative appeal of the penalty and its underlying conclusions. During the three months ended July 31, 2020, 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 €279,869.81 or approximately $331,000. The Company is appealing the decision of the Tribunal tax assessment to the Spanish National Court. Per the Company’s accounting policy, the Company recorded the additional penalty of €117,145.81 to Selling, general and administrative costs in the Statement of Operations. As of October 31, 2020 and April 30, 2020, the Company has reserved €279,869.81 (or approximately $326,000) and €162,724 (or approximately $177,000), respectively, for the penalty in Accrued expenses in the Consolidated Balance Sheets.

Commitments and Contingencies

6 Months Ended

Oct. 31, 2020

Commitments and Contingencies Disclosure [Abstract]

(16) Commitments and Contingencies

Employment Litigation

On June 10, 2014, the Company announced that it had terminated Charles Dunleavy as its Chief Executive Officer and as an employee of the Company for cause, effective June 9, 2014, and that Mr. Dunleavy had also been removed from his position as Chairman of the Board of Directors. On June 17, 2014, Mr. Dunleavy wrote to the Company stating that he had retained counsel to represent him in connection with an alleged wrongful termination of his employment. On July 28, 2014, Mr. Dunleavy resigned from the Board and the boards of directors of the Company’s subsidiaries.

On August 28, 2018, counsel for Mr. Dunleavy filed a demand for arbitration, captioned Charles F. Dunleavy v. Ocean Power Technologies, Inc., Case No. 01-18-0003-2374, before the American Arbitration Association in New Jersey. The demand names Ocean Power Technologies, Inc. as the respondent and alleges various claims and seeks declaratory relief and permanent injunction. The demand seeks damages in the amount of $5 million for compensatory and punitive damages, plus interest and attorneys’ fees as well as certain equitable relief. On November 8, 2018, the Company through counsel responded to the demand for arbitration, denied all allegations, and asserted various affirmative defenses. The final day of hearing occurred in Princeton, New Jersey on July 15, 2020. Post-hearing briefs were filed on September 22, 2020. As of October 31, 2020, the Company has not accrued any provision related to this matter as we believe a loss is not probable and any possible loss cannot be reasonably estimated.

Nasdaq Delisting Notification

On March 3, 2020, the Company received a notification from the Nasdaq indicating that the minimum bid price of the Company’s common stock has been below $1.00 per share for 30 consecutive business days and as a result, the Company is not in compliance with the minimum bid price requirement for continued listing. The Nasdaq notice has no immediate effect on the listing or trading of the Company’s common stock. Under the Nasdaq Listing Rules, the Company has a grace period of 180 calendar days, or until August 31, 2020, in which to regain compliance with the minimum bid price rule. To regain compliance, the closing bid price of the Company’s common stock must meet or exceed $1.00 per share for a minimum of ten consecutive business days during this grace period. On August 21, 2020, the Company received notification from Nasdaq that, as a result of the closing bid price of the Company’s common stock being over $1.00 for 10 consecutive trading days, the Company has regained compliance with Listing Rule 5550(a)(2) to maintain the listing of its common stock on Nasdaq and Nasdaq considers the matter 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. In connection with the tax audit, the Spanish tax inspector challenged the Company’s recognition of grant funds received in 2011 to 2014 from the European Commission in connection with the Company’s Waveport project. On July 30, 2018, the 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. On August 30, 2018, the Company filed an administrative appeal of the penalty and its underlying conclusions. During the three months ended July 31, 2020, 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 €279,869.81 or approximately $331,000. The Company is appealing the decision of the Tribunal tax assessment to the Spanish National Court. Per the Company’s accounting policy, the Company recorded the additional penalty of €117,145.81 to Selling, general and administrative costs in the Statement of Operations. As of October 31, 2020 and April 30, 2020, the Company has reserved €279,869.81 (or approximately $326,000) and €162,724 (or approximately $177,000), respectively, for the penalty in Accrued expenses in the Consolidated Balance Sheets.