Note 10. Commitments and Contingencies

Other Liabilities

The $43.6 million balance recorded in other liabilities is conditional, and will only be due and payable, upon the Company achieving a qualifying “Revenue” event, as defined below. The Company has agreed to pay 20% of its qualifying Revenue generated in each calendar year, if any, with such payments to be applied to reduce the balance until it is repaid in full. Interest will not accrue on the balance throughout the prospective repayment period. Revenue is defined as:

“…the gross revenue generated by Client and its Affiliates, less the following items (if not previously deducted from the amount invoiced): (a) reasonable and customary trade, quantity and cash discounts actually granted and legally permitted wholesaler chargebacks actually paid or credited by Client and its Affiliates to wholesalers of products; (b) reasonable, customary and legally permitted rebates and retroactive price reductions actually granted; (c) freight charges for the delivery of products; (d) the portion of the administrative fees paid during the relevant time period to group purchasing organizations, pharmaceutical benefit managers and/or government-mandated Medicare or Medicaid Prescription Drug Plans relating specifically to the product; and (e) sales, use or excise taxes imposed and actually paid in connection with the sale of products (but excluding any value added taxes or taxes based on income or gross receipts).”

PRO 140 Acquisition and Licensing Arrangements

We originally acquired leronlimab, as well as certain other related assets, including the existing inventory of PRO 140 bulk drug substance, intellectual property and FDA regulatory filings, pursuant to an Asset Purchase Agreement, dated as of July 25, 2012, and effective October 16, 2012 (the “Progenics Purchase Agreement”), between the Company and Progenics. Pursuant to the Progenics Purchase Agreement, we are required to pay Progenics a milestone payment and royalties as follows: (i) $5,000,000 at the time of the first U.S. new drug application approval by the FDA or other non-U.S. approval for the sale of leronlimab; and (ii) royalty payments of up to 5% on net sales during the period beginning on the date of the first commercial sale of leronlimab until the later of (a) the expiration of the last to expire patent included in the acquired assets, and (b) 10 years, in each case determined on a country-by-country basis. To the

extent that such remaining milestone payment and royalties are not timely made, under the terms of the Progenics Purchase Agreement, Progenics has certain repurchase rights relating to the assets sold to us thereunder.

Payments to Progenics are in addition to payments due under the PDL License, between Protein Design Labs (now AbbVie Inc.) and Progenics, which was assigned to us in the Progenics Purchase Agreement, pursuant to which we have an exclusive worldwide license to develop, make, have made, import, use, sell, offer to sell or have sold products that incorporate the humanized form of the leronlimab antibody developed under the agreement. Pursuant to the PDL License, we are required to pay AbbVie Inc. milestone payments and royalties as follows: (i) $500,000 upon filing a Biologic License Application with the FDA or non-U.S. equivalent regulatory body; (ii) $500,000 upon FDA approval or approval by another non-U.S. equivalent regulatory body; and (iii) royalties of up to 3.5% of net sales for the longer of 10 years and the date of expiration of the last to expire licensed patent. Additionally, the PDL License provides for an annual maintenance fee of $150,000 until royalties paid exceed that amount. To the extent that such remaining milestone payments and royalties are not timely made, under the terms of the PDL License, AbbVie Inc. has certain termination rights relating to our license of leronlimab thereunder.

Effective July 29, 2015, we entered into a License Agreement (the “Lonza Agreement”) with Lonza covering Lonza’s “system know-how” technology with respect to our use of proprietary cell lines to manufacture new leronlimab material. The Lonza Agreement provides for an annual license fee and future royalty payments, both of which vary based on whether Lonza or we or our strategic partner manufactures leronlimab. We currently use two independent parties as contract manufacturers for leronlimab, and continually review this arrangement. Should the arrangement continue as-is, an annual license fee of £0.3 million (approximately $0.35 million at current exchange rate) would continue to apply, as well as a royalty, of up to 2% of the net selling price upon commercialization of leronlimab, excluding value added taxes and similar amounts.

Operating Leases

We lease our principal office location in Vancouver, Washington (the “Vancouver Lease”). The Vancouver Lease expires on May 31, 2029. Consistent with the guidance in ASC 842, Leases, we have recorded this lease in our consolidated balance sheet as an operating lease. For the purpose of determining the right of use asset and associated lease liability, we determined that the renewal of the Vancouver lease was not reasonably probable. The lease does not include any restrictions or covenants requiring special treatment under ASC 842, Leases. Operating lease costs for the fiscal years ended May 31, 2026 and 2025 were approximately $0.1 million and $0.1 million, respectively. Operating lease right-of-use assets are included in other non-current assets and the current portion of operating lease liabilities are included in accrued liabilities and compensation on the consolidated balance sheets. The following table summarizes the operating lease balances.

Supplemental information related to the operating lease was as follows:

Legal Proceedings

On November 23, 2025, the Company recorded an accrual of approximately $15.4 million, which was revalued to approximately $15.3 million as of May 31, 2026, related to the Securities Class Action Lawsuits described below. The Company did not record any other accruals related to the outcomes of the legal matters described below. It is not possible to determine the outcome of these proceedings, including the defense and other litigation-related costs and expenses that may be incurred by the Company, as the outcomes of legal proceedings are inherently uncertain. Therefore, it is possible that the ultimate outcome of any proceeding, if in excess of a recognized accrual, if any, could be material to the Company’s consolidated financial statements.

Conclusion of Investigations by Securities and Exchange Commission and Department of Justice

In September 2025, the SEC and DOJ informed the Company that their respective investigations were effectively closed, and that nothing further was required of the Company.

Securities Class Action Lawsuits

On March 17, 2021, a stockholder filed a putative class-action lawsuit (the “March 17, 2021 lawsuit”) in the U.S. District Court for the Western District of Washington against the Company and certain former officers. The complaint generally alleges the defendants made false and misleading statements regarding the viability of leronlimab as a potential treatment for COVID-19. On April 9, 2021, a second stockholder filed a similar putative class action lawsuit in the same court, which the plaintiff voluntarily dismissed without prejudice on July 23, 2021. On August 9, 2021, the court appointed lead plaintiffs for the March 17, 2021 lawsuit. On December 21, 2021, lead plaintiffs filed an amended complaint, which is brought on behalf of an alleged class of those who purchased the Company’s common stock between March 27, 2020 and May 17, 2021. The amended complaint generally alleges that the defendants violated Sections 10(b) and/or 20(a) of the Securities Exchange Act of 1934, as amended (the “Exchange Act”) and Rule 10b-5 promulgated thereunder by making purportedly false or misleading statements concerning, among other things, the safety and efficacy of leronlimab as a potential treatment for COVID-19, the Company’s CD10 and CD12 clinical trials and its human immunodeficiency virus (“HIV”) Biologic License Application (“BLA”). The amended complaint also alleges that the individual defendants violated Section 20A of the Exchange Act by selling shares of the Company’s common stock purportedly while in possession of material nonpublic information. The amended complaint seeks, among other relief, a ruling that the case may proceed as a class action and unspecified damages and attorneys’ fees and costs. On February 25, 2022, the defendants filed a motion to dismiss the amended complaint. On June 24, 2022, lead plaintiffs filed a second amended complaint. The second amended complaint was brought on behalf of an alleged class of those who purchased the Company’s common stock between March 27, 2020 and March 30, 2022, makes similar allegations, names the same defendants, and asserts the same claims as the prior complaint, adds a claim for alleged violation of Section 10(b) of the Exchange Act and Rule 10b-5(a) and (c) promulgated thereunder, and seeks the same relief as the prior complaint. All defendants filed motions to dismiss the second amended complaint in whole or in part. By order dated June 25, 2025, the court denied defendants’ motions to dismiss.

On November 23, 2025, the Company reached an agreement in principle to settle the putative class-action lawsuit. The agreement in principle provides for a payment by the Company to the class of $500,000 in cash and 49 million shares of common stock of the Company in exchange for the dismissal and release of all claims against all defendants in the class action. The agreement is subject to final documentation, court approval and other conditions. On March 18, 2026, the lead plaintiffs filed a motion for preliminary approval of the settlement. On June 18, 2026, the court granted the preliminary approval of the settlement and scheduled a hearing for November 2, 2026 to consider, among other matters, the final approval of the settlement.

There can be no assurances as to the ultimate outcome of the class action, including that the court will grant final approval of the settlement on the terms the court has preliminary approved, or that any revised settlement terms, if applicable, will be finalized by the parties and approved by the court. The settlement agreement does not constitute an admission of, and the Company does not admit, any fault or liability. If the settlement cannot be finalized by the parties or is not approved by the court, the Company will defend the class action vigorously and believes there are meritorious defenses and legal standards that must be met for, among other things, success by the plaintiffs on the merits. If the parties are unable to finalize the settlement, the class action could have a material adverse effect on the Company’s

financial condition, results of operations and cash flows.

Shareholder Derivative Lawsuits

On June 4, 2021, a stockholder filed a purported derivative lawsuit against certain of the Company’s former officers and directors, and the Company as a nominal defendant, in the U.S. District Court for the Western District of Washington. Two additional shareholder derivative lawsuits were filed against the same defendants in the same court on June 25, 2021 and August 18, 2021, respectively. The court has consolidated these three lawsuits for all purposes (“Consolidated Derivative Suit”). On January 20, 2022, the plaintiffs filed a consolidated complaint. The consolidated complaint generally alleges that the director defendants breached their fiduciary duties by allowing the Company to make false and misleading statements regarding, among other things, the safety and efficacy of leronlimab as a potential treatment for COVID-19, the Company’s CD10 and CD12 clinical trials and its HIV BLA, and by failing to maintain an adequate system of oversight and controls. The consolidated complaint also asserts claims against one or more individual defendants for waste of corporate assets, unjust enrichment, contribution for alleged violations of the federal securities laws and for breach of fiduciary duty arising from alleged insider trading. The consolidated complaint seeks declaratory and equitable relief, an unspecified amount of damages and attorneys’ fees and costs.

On January 29, 2024, two purported stockholders filed a purported derivative lawsuit against certain of the Company’s former officers, certain current and former directors, and the Company as a nominal defendant, in the Delaware Court of Chancery. The complaint generally makes allegations similar to those set forth in the Consolidated Derivative Suit and asserts that the individual defendants breached their fiduciary duties by allowing the Company to make false and misleading statements and by failing to maintain an adequate system of oversight and controls. The complaint also asserts claims against certain individual defendants for breach of fiduciary duty arising from alleged insider trading.

On June 20, 2025, two other purported stockholders filed a purported derivative lawsuit against certain of the Company’s former officers, certain former and current directors, a third-party individual, and the Company as a nominal defendant, in the Delaware Court of Chancery. The complaint generally asserts that the individual defendants breached their fiduciary duties by allowing the Company to make false and misleading statements, by failing to maintain an adequate system of oversight and controls and/or by purportedly wrongfully refusing plaintiffs’ demands that the Company’s board investigate and initiate claims against certain of the Company’s former officers and directors based on allegations and claims similar to those set forth in the complaint. The complaint also asserts claims against certain individual defendants arising from alleged insider trading. The court has consolidated this lawsuit with the January 2024 lawsuit, and the plaintiffs have filed a consolidated complaint that makes allegations and asserts claims similar to those set forth in the January 2024 and June 2025 lawsuits.

The Company and the individual defendants deny all allegations of wrongdoing in the complaints and intend to vigorously defend the litigation. In light of the fact that the suit(s) is/are in an early stage and the claims do not specify an amount of damages, the Company cannot predict the ultimate outcome of the matter(s) and cannot reasonably estimate the potential loss or range of loss the Company may incur.

Investor Lawsuit Seeking Issuance of Additional Shares

In January 2025, two former investors, who are also current shareholders, filed an action against the Company in relation to a dispute over how many shares were issued to them following their direct investment(s) with the Company. The former investors claim that the final pricing utilized to calculate the issuance of shares to them in 2022 was incorrect, and that they are entitled to more shares than were issued. The complaint presents legal claims based on breach of fiduciary duty, misrepresentation, fraud, negligence, theft and breach of contract.

The Company's position is that the claims are without any factual support, or support under applicable law and/or the underlying investment documents. The Company views this action as an attempt to extract more shares without further/fair investment and intends to vigorously defend itself.