Note 4. Convertible Instruments and Accrued Interest

Convertible Preferred Stock

The following table presents the number of potentially issuable shares of common stock, should shares of preferred stock and amounts of undeclared and accrued preferred dividends be converted to common stock.

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Under the Company’s Amended and Restated Certificate of Incorporation, as amended (the “Certificate of Incorporation”), dividends on its outstanding shares of Series B Convertible Preferred Stock (the “Series B Preferred Stock”) may be paid in cash or shares of the Company’s common stock at the election of the Company. Dividends on outstanding shares of Series C Convertible Preferred Stock (the “Series C Preferred Stock”) and Series D Convertible Preferred Stock (the “Series D Preferred Stock”) are payable in cash or shares of common stock at the election of the holder. The preferred stockholders have the right to dividends only when and if declared by the Company’s Board of Directors. Shares of common stock presented in the table above represent the number of shares that would have been issued had the dividend been paid in shares of the Company’s common stock as of the end of each presented period; undeclared dividends of Series C Preferred Stock and Series D Preferred Stock are accrued as of May 31, 2025. Due to the Company’s accumulated deficit of approximately $887.8 million as of May 31, 2025, under Section 170 of the Delaware General Corporation Law, the Company is prohibited from paying any dividends, whether in cash, other property, or in shares of capital stock, until the deficiency in the amount of capital represented by the Company’s issued and outstanding preferred stock shall have been repaired. Refer to the discussion below for additional information.

Series B Convertible Preferred Stock

Each share of the Series B Preferred Stock is convertible into ten shares of the Company’s common stock. Dividends are payable to the Series B Preferred stockholders when and as declared by the Board at the rate of $0.25 per share per annum. Such dividends are cumulative and accrue whether or not declared and whether or not there are any profits, surplus, or other funds or assets of the Company legally available therefor. At the option of the Company, dividends on the Series B Preferred Stock may be paid in cash or restricted shares of the Company’s common stock, valued at $0.50 per share. The preferred shareholders can only convert their shares to shares of common stock if the Company has sufficient authorized shares of common stock at the time of conversion. The Series B Preferred Stock has liquidation preferences over the common shares at $5.00 per share, plus any accrued and unpaid dividends. Except as provided by law, the Series B holders have no voting rights. The Company does not accrue dividends on Series B preferred stock until such dividends are declared.

Series C Convertible Preferred Stock

The Series C Certificate of Designation provides, among other things, that holders of Series C Preferred Stock shall be entitled to receive, when and as declared by the Board and out of any assets at the time legally available therefor, cumulative dividends at the rate of ten percent (10%) per share per annum of the stated value of the Series C Preferred Stock, which is $1,000 per share (the “Series C Stated Value”). Any dividends paid by the Company will be paid to the holders of Series C Preferred Stock prior and in preference to any payment or distribution to holders of common stock. Dividends on the Series C Preferred Stock are cumulative, and will accrue and be compounded annually, whether or not declared and whether or not there are any profits, surplus, or other funds or assets of the Company legally available therefor. There are no sinking fund provisions applicable to the Series C Preferred Stock. The Series C Preferred Stock does not have redemption rights. Dividends, if declared by the Board, are payable to holders in arrears on December 31 of each year. Subject to the provisions of applicable Delaware law, the holder may elect to be paid in cash or in restricted shares of common stock, with the number of shares to be based on the conversion price then in effect. In the event of liquidation, dissolution, or winding up of the Company, the holders of Series C Preferred Stock will be entitled to receive, on a pari passu basis with the holders of the Series D Preferred Stock and in preference to any payment or distribution to any holders of the Series B Preferred Stock or common stock, an amount per share equal to the Series C Stated Value plus the amount of any accrued and unpaid dividends. If, at any time while the Series C Preferred Stock is outstanding, the Company effects a reorganization, merger or consolidation of the Company, sale of substantially all of its assets, or other specified transaction (each, as defined in the Series C Certificate of Designation, a “Fundamental Transaction”), a holder of the Series C Preferred Stock will have the right to receive any shares of the acquiring corporation or other consideration it would have been entitled to receive if it had been a holder of the number of shares of common stock then issuable upon conversion in full of the Series C Preferred Stock immediately prior to the Fundamental Transaction. Each share of Series C Preferred Stock is convertible at any time at the holder’s option into that number of fully paid and nonassessable shares of common stock determined by dividing the Series C Stated Value by the conversion price of $0.50 (subject to adjustment as set forth in the Series C Certificate of Designation). No fractional shares will be issued upon the conversion of the Series C Preferred Stock. Except as otherwise provided in the Series C Certificate of Designation or as otherwise required by law, the Series C Preferred Stock has no voting rights.

Series D Convertible Preferred Stock

The Series D Certificate of Designation provides, among other things, that holders of Series D Preferred Stock shall be entitled to receive, when and as declared by the Company’s Board of Directors and out of any assets at the time legally available therefor, cumulative dividends at the rate of ten percent (10%) per share per annum of the stated value of the Series D Preferred Stock, which is $1,000 per share (the “Series D Stated Value”). Any dividends paid by the Company will first be paid to the holders of Series D Preferred Stock prior and in preference to any payment or distribution to holders of common stock. Dividends on the Series D Preferred Stock are cumulative, and will accrue and be compounded annually, whether or not declared and whether or not there are any profits, surplus, or other funds or assets of the Company legally available therefor. There are no sinking fund provisions applicable to the Series D Preferred Stock. The Series D Preferred Stock does not have redemption rights. Dividends, if declared by the Board, are payable to holders in arrears on December 31 of each year. Subject to the provisions of applicable Delaware law, the holder may elect to be paid in cash or in restricted shares of common stock, with the number of shares to be based on the conversion price then in effect. In the event of liquidation, dissolution, or winding up of the Company, the holders of Series D Preferred Stock will be entitled to receive, on a pari passu basis with the holders of the Series C Preferred Stock and in preference to any payment or distribution to any holders of the Series B Preferred Stock, $0.001 par value per share, or common stock, an amount per share equal to the Series D Stated Value plus the amount of any accrued and unpaid dividends. If, at any time while the Series D Preferred Stock is outstanding, the Company effects any reorganization, merger or consolidation of the Company, sale of substantially all of its assets, or other specified transaction (each, as defined in the Series D Certificate of Designation, a “Fundamental Transaction”), a holder of the Series D Preferred Stock will have the right to receive any shares of the acquiring corporation or other consideration it would have been entitled to receive if it had been a holder of the number of shares of common stock then issuable upon conversion in full of the Series D Preferred Stock immediately prior to the Fundamental Transaction. Each share of Series D Preferred Stock is convertible at any time at the holder’s option into that number of fully paid and nonassessable shares of common stock determined by dividing the Series D Stated Value by the conversion price of $0.80 (subject to adjustment as set forth in the Series D Certificate of Designation). No fractional shares will be issued upon the conversion of the Series D Preferred Stock. Except as otherwise provided in the Series D Certificate of Designation or as otherwise required by law, the Series D Preferred Stock has no voting rights.

Convertible Notes and Accrued Interest

The outstanding balance of convertible notes, the terms of which are described in more detail below, including accrued interest, were as follows:

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Changes in the outstanding balance of convertible notes, including accrued interest, were as follows:

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Convertible Note – April 2, 2021 Note

On April 2, 2021, the Company entered into a securities purchase agreement pursuant to which the Company issued a secured convertible promissory note in the initial principal amount of $28.5 million (the “April 2, 2021 Note”). The current maturity date is April 5, 2026. See April 2, 2021 and April 23, 2021 Note Extensions below. The Company received consideration of $25.0 million, reflecting an original issue discount of $3.4 million and issuance costs of $0.1 million.

Beginning in April 2025, in connection with extension of the maturity date, interest accrues at an annual rate of 6% on the outstanding balance, a decrease from an annual rate of 10%; provided that the rate would increase to the lesser of 22% per annum or the maximum rate permitted by applicable law upon occurrence of an event of default. In addition, upon any event of default, the investor may accelerate the outstanding balance payable under the April 2, 2021 Note; upon such acceleration, the outstanding balance will increase automatically by 15%, 10%, or 5%, depending on the nature of the event of default. The events of default are listed in Section 4 of the April 2, 2021 Note filed as Exhibit 4.1 to the Company’s Current Report on Form 8-K filed on April 8, 2021, and listed as Exhibit 4.6 in Item 15 to this report. The April 2, 2021 Note is secured by all the assets of the Company, excluding the Company’s intellectual property.

Pursuant to the terms of the securities purchase agreement and the April 2, 2021 Note, the Company must obtain the investor’s consent before assuming additional debt with aggregate net proceeds to the Company of less than $50.0 million. In the event of any such approval, the outstanding principal balance of the April 2, 2021 Note will increase automatically by 5% upon the issuance of such additional debt.

The investor may convert all or any part of the outstanding balance of the April 2, 2021 Note into shares of common stock at an initial conversion price of $10.00 per share upon five trading days’ notice, subject to certain adjustments and volume and ownership limitations. In addition to standard anti-dilution adjustments, the conversion price of the April 2, 2021 Note is subject to full-ratchet anti-dilution protection, pursuant to which the conversion price will be automatically reduced to equal the effective price per share in any new offering by the Company of equity securities that have registration rights, are registered, or become registered under the Securities Act, as amended. The April 2, 2021 Note provides for liquidated damages upon failure to deliver common stock within specified timeframes and requires the Company to maintain a share reservation of 6.0 million shares of common stock. The investor may redeem any portion of the note, at any time beginning six months after the issue date upon three trading days’ notice, subject to a maximum monthly redemption amount of $3.5 million. The April 2, 2021 Note requires the Company to satisfy its redemption obligations in cash within three trading days of the Company’s receipt of such notice. The Company may prepay the outstanding balance of the note, in part or in full, plus a 15% premium, at any time upon 15 trading days’ notice.

The conversion feature of the April 2, 2021 Note was analyzed under ASC 815, Derivatives and Hedging, to determine if it achieved equity classification or required bifurcation as a derivative instrument. The embedded conversion feature was considered indexed to the Company’s own stock and met the conditions for equity classification. Accordingly, the embedded conversion feature did not require bifurcation from the host instrument. The Company determined there was no beneficial conversion feature since the effective conversion rate was greater than the market value of the Company’s common stock upon issuance. Certain default put provisions were considered not to be clearly and closely related to the host instrument, but the Company concluded that the value of these default put provisions was de minimis. The Company evaluates the value of the default put provisions each reporting period to determine if the value has become material to the financial statements.

During the fiscal year ended May 31, 2024, in satisfaction of redemptions, the Company and the April 2, 2021 Noteholder entered into six exchange agreements, pursuant to which the April 2, 2021 Note was partitioned into new notes (the “Partitioned Notes”) with an aggregate principal amount of approximately $3.3 million, which was exchanged concurrently with the issuance of an aggregate amount of approximately 20.4 million shares of common stock. The outstanding balance of the April 2, 2021 Note was reduced by the Partitioned Notes to a principal amount of $2.8 million. The Company accounted for the Partitioned Notes and exchange settlements as induced conversions, and, accordingly, in the fiscal year ended May 31, 2024, the Company recorded a non-cash loss on convertible debt induced conversion of $4.7 million.

Convertible Note – April 23, 2021 Note

On April 23, 2021, the Company entered into a securities purchase agreement pursuant to which the Company issued a secured convertible promissory note to an institutional accredited investor affiliated with the holder of the April 2, 2021 Note in the initial principal amount of $28.5 million (the “April 23, 2021 Note”). The current maturity date is April 23, 2026. See April 2, 2021 and April 23, 2021 Note Extensions below. The Company received consideration of $25.0 million, reflecting an original issue discount of $3.4 million and issuance costs of $0.1 million. The April 23, 2021 Note is secured by all the assets of the Company, excluding the Company’s intellectual property.

Interest accrues at an annual rate of 6% on the outstanding balance of the April 23, 2021 Note, amended from an annual rate of 10%, with the rate increasing to the lesser of 22% per annum or the maximum rate permitted by applicable law upon the occurrence of an event of default. In addition, upon any event of default, the investor may accelerate the outstanding balance payable under the April 23, 2021 Note; upon such acceleration, the outstanding balance will increase automatically by 15%, 10%, or 5%, depending on the nature of the event of default. The events of default are listed in Section 4 of the April 23, 2021 Note filed as Exhibit 4.1 to the Company’s Current Report on Form 8-K filed on April 29, 2021, and listed as Exhibit 4.7 in Item 15 to this report.

The investor may convert all or any part of the outstanding balance into shares of common stock at an initial conversion price of $10.00 per share upon five trading days’ notice, subject to certain adjustments and volume and ownership limitations specified in the April 23, 2021 Note. In addition to standard anti-dilution adjustments, the conversion price of the April 23, 2021 Note is subject to full-ratchet anti-dilution protection, pursuant to which the conversion price will be automatically reduced to equal the effective price per share in any new offering by the Company of equity securities that have registration rights, are registered, or become registered under the Securities Act. The April 23, 2021 Note provides for liquidated damages upon failure to deliver common stock within specified timeframes and requires the Company to maintain a share reservation of 6.0 million shares of common stock.

The investor may redeem any portion of the April 23, 2021 Note, at any time beginning six months after the issue date, upon three trading days’ notice, subject to a maximum monthly redemption amount of $7.0 million. The April 23, 2021 Note requires the Company to satisfy its redemption obligations in cash within three trading days of the Company’s receipt of such notice. The Company may prepay the outstanding balance of the April 23, 2021 Note, in part or in full, plus a 15% premium, at any time upon 15 trading days’ notice.

Pursuant to the terms of the securities purchase agreement and the April 23, 2021 Note, the Company must obtain the investor’s consent before assuming additional debt with aggregate net proceeds to the Company of less than $75.0 million. In the event of any such approval, the outstanding principal balance of the April 23, 2021 Note will increase automatically by 5% upon the issuance of such additional debt.

The conversion feature in the April 23, 2021 Note was analyzed under ASC 815, Derivatives and Hedging, to determine if it achieved equity classification or required bifurcation as a derivative instrument. The embedded conversion feature was considered indexed to the Company’s own stock and met the conditions for equity classification. Accordingly, the embedded conversion feature does not require bifurcation from the host instrument. The Company determined there was no beneficial conversion feature since the effective conversion rate was greater than the market value of the Company’s common stock upon issuance. Certain default put provisions were not considered to be clearly and closely related to the host instrument, but the Company concluded that the value of these default put provisions was de minimis. The Company evaluates the value of the default put provisions each reporting period to determine if the value has become material to the financial statements.

During the fiscal year ended May 31, 2025, in satisfaction of redemptions, the Company and the April 23, 2021 Noteholder entered into seven exchange agreements, pursuant to which the April 23, 2021 Note was partitioned into the Partitioned Notes with an aggregate principal amount of $4.5 million, which was exchanged concurrently with the issuance of an aggregate amount of approximately 25.4 million shares of common stock. The outstanding balance of the April 23, 2021 Note was reduced by the Partitioned Notes to a principal amount of $24.4 million. The Company accounted for the Partitioned Notes and exchange settlements where the shares exchanged were worth more than principal extinguished as induced conversions, and, accordingly, in the fiscal years ended May 31, 2025 and May 31, 2024, the Company recorded a non-cash loss on convertible debt induced conversion of approximately $1.2 million and $1.9 million, respectively. The Company recognized an approximate $0.4 million gain on restructuring of payables

during the fiscal year ended May 31, 2025 for the Partitioned Notes and the exchange settlements where the shares exchanged were worth less than principal extinguished.

The holders of the April 2 and April 23 Notes have waived provisions in the notes that would have resulted in the imposition of a default interest rate, a downward adjustment in the conversion price, or any other default, breach, or imposition of a penalty. The related transactions consisted of the issuance of shares of common stock and warrants issued through a placement agent.

April 2, 2021 Note and April 23, 2021 Note Extensions

In April 2023 the Company and the April 2, 2021 and April 23, 2021 noteholders entered into an amendment to each note that extended the maturity date an additional two years. In exchange, the Company agreed to pay the noteholders an extension fee equal to two and one-half percent (2.5%) of the outstanding balance of each note as of April 10, 2023. As a result, the balances of the April 2, 2021 Note and April 23, 2021 Note increased by $0.3 million and $0.9 million, respectively.

The Company accounted for the note extensions as an increase to the discount on the convertible notes payable and amortized the note extension fee until the extended maturity date, April 2025.

In April 2025, the Company and the April 2, 2021 and April 23, 2021 noteholders agreed to extend the maturity date of each of the notes by one year to April 2026 (the “Extension Period”) and to reduce the annual interest rate to 6%. The Company also agreed to make total monthly payments of $750,000 covering both notes during the Extension Period by issuing shares of common stock equal in value to each $750,000 monthly payment calculated based on the lower of (i) the previous trading day’s closing price, or (ii) the average of the five previous trading day closing prices.

In the event of a conflict, the terms in the April 2025 extensions supersede the terms of the original Notes and all prior amendments thereto.