OS Therapies
OSTX on NYSEAmerican. Market value $74m.
Should I look at this?
Look carefully before going further
Why it could be worth it
Nothing stands out yet.
What to watch out for
Read the warning sign in its own filings
This is not advice.
Who owns it
None of the long-term investors we follow own it. 29 funds in all.
Largest holders overall
- Vanguard Capital Management$1mAdded
- CM Management$760,000
- Geode Capital Management$573,408Added
- Howard Financial Services$471,202
- BlackRock$460,710Added
- Vanguard Fiduciary Trust$330,851Added
- State Street$228,190Added
- Marshall Wace, LLP$191,216New
- HighTower Advisors$162,545Added
- Northern Trust$134,552Added
From 13F filings for the quarter ended 30 June 2026.
Big holders and activists
3 investors own more than 5%.
- AYALA PHARMACEUTICALS, INC.Passive investor10.0%Since 9 April 2025
- Thomas A. Satterfield, Jr.Passive investor9.4%+3.5 ptsSince 30 June 2025
- Shalom AuerbachPassive investorat least 8.5%−1.4 pts(filed with 1 related holder)Since 29 July 2025
| Holder | Stake | Since | |
|---|---|---|---|
AYALA PHARMACEUTICALS, INC. Passive investor | 10.0% | 9 April 2025 | |
Thomas A. Satterfield, Jr. Passive investor | 9.4%+3.5 pts | 30 June 2025 | |
Shalom Auerbach Passive investor | at least 8.5%−1.4 pts (filed with 1 related holder) | 29 July 2025 |
From Schedule 13D and 13G filings: anyone owning more than 5% must file one.
What insiders did
No insider bought or sold on the open market in the last 12 months.
From Form 4 filings: insiders must report trades in their own company's shares within two days.
Warning signs in its filings
Problems the company itself reported to the SEC, in its own words.
2 serious warning signs in OS Therapies’ filings.
We look for five warning signs: doubt it can keep going, weak checks on its own accounts, a notice that its past accounts can't be relied on, a change of auditor, and one customer bringing in a big share of sales. We don't check lawsuits, investigations or debt yet.
We checked the auditor's report, internal controls, restatement notices, auditor changes and big customers in the 10-K filed 31 Mar 2026, plus the 10-Q filed 14 Aug 2026 and 10 later 8-Ks.
Doubt it can keep going
SeriousThe company or its auditor warned it may not have enough money to last the next year.
“These factors raise substantial doubt about the Company’s ability to continue as a going concern within one year after the date that the unaudited consolidated financial statements are issued.”
Show the full paragraph
As of June 30, 2026, the Company had cash and cash equivalents of $ 205,035 . Management has evaluated whether there are conditions and events, considered in the aggregate, that raise substantial doubt about the Company’s ability to continue as a going concern within one year after the date that these consolidated financial statements are issued. The Company’s current cash balance is insufficient to fund operations. During the six months ended June 30, 2026, the Company incurred significant expenses, primarily related to activities in preparation for potential regulatory approvals by the U.S. Food and Drug Administration and other countries’ regulatory authorities. The Company expects vendor and related costs associated with these efforts to total approximately $ 24.0 million and continue into the remainder of 2026. These factors raise substantial doubt about the Company’s ability to continue as a going concern within one year after the date that the unaudited consolidated financial statements are issued.
From the 10-Q filed 14 August 2026, Part I, Item 1. Financial Statements. Read it in the filing
Weak checks on its own accounts
SeriousThe company said its checks on its own accounts did not work at year end. Mistakes could slip into the numbers.
“Based on such assessment, management has concluded that our internal control over financial reporting was not effective as of the year ended December 31, 2025 to provide reasonable assurance regarding the reliability of financial reporting and the preparation of consolidated financial statements for external reporting purposes in accordance with U.S. GAAP.”
Show the full paragraph
Based on such assessment, management has concluded that our internal control over financial reporting was not effective as of the year ended December 31, 2025 to provide reasonable assurance regarding the reliability of financial reporting and the preparation of consolidated financial statements for external reporting purposes in accordance with U.S. GAAP. We reviewed the results of management’s assessment with the audit committee of our board of directors. We determined that we have inadequate segregation of duties as a result of limited personnel and insufficient written policies and procedures for accounting, information technology and financial reporting (no control procedures in place) and insufficient number of personnel with appropriate levels of accounting knowledge and experience in U.S. GAAP.
From the 10-K filed 31 March 2026, Item 9A. Controls and Procedures. Read it in the filing
A 10-K is the yearly report every US company files with the SEC. An 8-K is a short notice of a big event.
The deep dive
Everything above is arithmetic on public filings. The deep dive reads the last ten years of annual reports, the proxy statements, and the earnings calls, then argues the case the way Buffett, Klarman, and Hohn would, and checks every claim against the source.
- What the business is worth, as a range, and the margin of safety at today’s price
- Prices to start buying, buy, and buy hard
- The three things that would make this a mistake
- Every number footnoted to the filing it came from
Your first deep dive is free.
Not advice. Numbers on this page come from SEC filings and are updated each night; prices are updated again after the US market closes. The five-year figures are rounded.