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. 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.
Boundless Bio, Inc. reported that entities associated with Tang Capital Partners made open-market purchases of a total of 57,210 shares of common stock over three days. The buys on July 6–8, 2026 were executed at weighted-average prices between $2.46 and $2.49 per share.
Following these transactions, the indirect holdings reported as "By LP" increased to 2,698,518 shares of Boundless Bio common stock. Footnotes state that various Tang Capital funds collectively beneficially own these shares and that Kevin Tang has a pecuniary interest in the positions.
Boundless Bio, Inc. reported insider activity involving entities affiliated with ARCH Venture funds and investment committee member Kristina Burow. On July 1, 2026, a cashless stock option exercise for 16,000 shares of common stock at $1.03 per share was completed, followed by an open-market sale of 16,000 shares at $2.49 per share, with net proceeds remitted to ARCH funds. The filing also shows indirect holdings of 1,181,766, 828,570 and 683,759 shares of common stock as of that date.
Boundless Bio, Inc. received a Form 4 from ARCH-affiliated entities detailing a cashless stock option exercise and same-day sale tied to director Kristina Burow’s compensation. A stock option for 16,000 shares of common stock was exercised at $1.03 per share and the resulting 16,000 shares were sold in an open-market transaction at $2.49 per share. According to the footnotes, the net proceeds from this exercise and sale were remitted to ARCH Venture Fund IX, L.P., ARCH Venture Fund IX Overage, L.P., and ARCH Venture Fund X Overage, L.P., which continue to report substantial indirect holdings of Boundless Bio common stock.
Boundless Bio, Inc. insider entities affiliated with Kevin Tang reported open-market purchases of a total of 107,463 shares of Common Stock at prices around $2.49–$2.60 per share over three days. The transactions were made indirectly through limited partnerships managed by Tang Capital Management, LLC.
Following these purchases, the reporting entities collectively beneficially own 2,641,308 shares of Boundless Bio Common Stock, as described in the filing’s ownership breakdown for Tang Capital Partners, LP and related entities. All reported trades were classified as open-market purchases, with no sales or derivative transactions disclosed.