Welcome to our dedicated page for Boundless Bio SEC filings (Ticker: BOLD), a comprehensive resource for investors and traders seeking official regulatory documents including 10-K annual reports, 10-Q quarterly earnings, 8-K material events, and insider trading forms.
Boundless Bio, Inc. filings document a clinical-stage oncology issuer focused on ecDNA-directed cancer therapeutics, with formal disclosures on operating results, research programs, and material events. Recent 8-K reports furnish quarterly and annual financial results and business updates for BBI-940, KOMODO-1, and the discontinued POTENTIATE program involving BBI-355 and BBI-825.
Its proxy and current reports also cover board composition, director elections, auditor ratification, stockholder voting results, and facility-related obligations, including lease-termination arrangements. These filings frame the company’s clinical-development disclosures, public-company governance, capital allocation, and operating obligations.
Boundless Bio, Inc. (BOLD) amended its Merger Agreement with Serapha Bio, Inc. and Boulder Merger Sub Corp. on August 28, 2026. The amendment clarifies definitions around the Company Pre-Closing Financing and confirms that required minimum aggregate cash proceeds must be received at or around closing.
The amendment specifies that all outstanding Serapha restricted stock units will convert at closing into Boundless Bio restricted stock units, with share counts adjusted by the Exchange Ratio while preserving vesting and acceleration terms. It also introduces mechanics to deliver a portion of the Merger Consideration as pre-funded warrants with a de minimis exercise price instead of common stock when needed to keep each holder below its elected Beneficial Ownership Limitation.
In addition, the voting standard to increase Boundless Bio’s authorized common shares is changed to a majority of shares properly cast, rather than a majority of all shares outstanding. The filing includes a detailed form of pre-funded warrant that is subject to ownership caps, anti-dilution adjustments and allows cashless exercise.
Boundless Bio, Inc. (BOLD) reports that on August 28, 2026 it entered into Amendment No. 1 to its Agreement and Plan of Merger and Reorganization with Boulder Merger Sub Corp. and Serapha Bio, Inc. The amendment refines mechanics around the planned merger under which Serapha will become a wholly owned subsidiary of Boundless Bio.
The amendment clarifies definitions and provisions related to the planned Company Pre-Closing Financing, specifies that all outstanding Serapha restricted stock units will convert into Boundless Bio restricted stock units adjusted by the Exchange Ratio, and introduces pre-funded warrants with a $0.00001 per-share exercise price as merger consideration when issuing common stock would breach a holder’s Beneficial Ownership Limitation. It also lowers the voting standard for increasing authorized Boundless Bio common shares to a majority of shares properly cast, rather than a majority of shares outstanding and entitled to vote. All other merger terms remain as previously disclosed. The company highlights multiple risks that could affect completion and outcomes of the merger and related financing, including regulatory approvals, satisfaction of closing conditions, exchange ratio adjustments, market price movements, and potential non-consummation of the pre-closing financing.
Boundless Bio, Inc. (BOLD) had a significant shareholder group associated with Kevin Tang report the sale of 18,300 shares of Common Stock on 2026-08-26 at a weighted-average price of $2.97 per share, in transactions ranging from $2.90 to $3.03. Following this sale, entities affiliated with Tang Capital Partners beneficially hold 2,840,635 shares of Boundless Bio indirectly through several Tang Capital entities. The reporting persons stated they delivered to Boundless Bio the full disgorgeable profit of $10,046.70 arising from this sale and indicated that the transactions were not effected under a Rule 10b5-1 trading plan.
Boundless Bio, Inc. (BOLD) discloses that Zachary Hornby has filed a Schedule 13G reporting beneficial ownership of its common stock. As of August 17, 2026, he beneficially owns 2,426,857 shares of common stock, including stock options exercisable within 60 days, representing 9.8% of the outstanding class based on 22,747,985 shares outstanding as of August 5, 2026. He reports sole voting and dispositive power over all of these shares and no shared voting or dispositive power.
Boundless Bio, Inc. has disclosed that private investment funds managed by ADAR1 Capital Management, LLC beneficially own 1,968,216 shares of its common stock. This represents 8.8% of Boundless Bio’s common stock, based on 22,475,000 shares outstanding as of June 30, 2026.
The shares are reported as being subject to shared voting and dispositive power by ADAR1 Capital Management and Daniel Schneeberger, who is the sole manager of ADAR1 Capital Management and may be deemed to indirectly beneficially own the same 1,968,216 shares.
Boundless Bio, Inc. received an amended Schedule 13G filing from a group of Citadel-related entities and Kenneth Griffin regarding their holdings of common stock. Based on 22,474,777 Shares outstanding as of June 15, 2026, Citadel Securities LLC may be deemed to beneficially own 65,617 Shares, while each of Citadel Securities Group LP, Citadel Securities GP LLC and Mr. Griffin may be deemed to beneficially own 145,118 Shares, or 0.6% of the outstanding Shares. The filing confirms that the Reporting Persons collectively report ownership of 5 percent or less of this class, with only shared, and no sole, voting or dispositive power over these Shares.
Boundless Bio, Inc. reported continued clinical‑stage losses with no product revenue. For the three and six months ended June 30, 2026, net loss was $23.7 million and $37.2 million, or $1.06 and $1.66 per share, respectively. Cash, cash equivalents and short‑term investments totaled $72.6 million, which management believes will fund operations for at least twelve months from issuance of these financial statements, without giving effect to the proposed merger or anticipated dividend.
On June 22, 2026, Boundless agreed to merge with Serapha Bio, Inc.. After closing, Serapha stockholders are expected to own 96.31% of the combined company and Boundless stockholders 3.69%, on a fully diluted basis. Closing is subject to stockholder approvals, continued Nasdaq listing, SEC effectiveness of a Form S‑4, and Serapha obtaining at least $200 million in related financings. Boundless expects to declare a pre‑closing cash dividend estimated at $44–48 million in aggregate for existing stockholders.
Boundless is pivoting away from its ecDNA‑directed oncology programs after trial data and pharmacokinetic exposure for lead candidate BBI‑940 were deemed insufficient to support further development. The company terminated its large San Diego headquarters lease, incurring $10.5 million in termination consideration and $1.6 million of asset impairments, and entered a smaller short‑term lease. It also announced a workforce reduction of approximately 75%, recording $2.8 million in severance charges and estimating total one‑time restructuring costs of $3–5 million. If the merger does not close, Boundless indicates it may seek alternative financings, other strategic transactions, or liquidation.
Boundless Bio, Inc. reported that investment entities managed by Tang Capital Management, associated with ten percent owner Kevin Tang, purchased a total of 4,863 shares of common stock in open market or private transactions at $2.44 per share between July 17 and July 21, 2026, through indirect ownership.
Tang Capital Management LLC and Kevin Tang, both reported as 10% owners of Boundless Bio, Inc., disclosed open‑market purchases of 63,969 shares of common stock on July 14–16, 2026 at weighted‑average prices between $2.41 and $2.44 per share.
After these transactions, Tang‑affiliated entities TCP, TCPI, TCP III and TCP IV beneficially own a combined 2,854,072 shares, including 654,055, 891,914, 654,048 and 654,055 shares respectively, in which Kevin Tang has a pecuniary interest through his roles with these entities.
Boundless Bio, Inc. ten percent owner entities associated with Kevin Tang reported open-market purchases of a total of 91,585 shares of Common Stock on July 9, 10 and 13, 2026, at weighted-average prices of $2.48, $2.43 and $2.42 per share, respectively. Following the latest transaction, investment vehicles managed by Tang Capital Management LLC, in which Kevin Tang has a pecuniary interest, beneficially own 2,790,103 shares of Boundless Bio common stock indirectly.