Published: May 13, 2026
Category: AI / Finance / Venture Capital
Artificial intelligence company Anthropic has issued a strong warning to investors regarding unauthorized platforms claiming to offer access to the company’s shares through secondary markets and investment vehicles.
The warning, published on Anthropic’s support page, specifically named several firms — including Open Doors Partners, Unicorns Exchange, Pachamama Capital, Lionheart Ventures, Hiive, Forge Global, Sydecar, and Upmarket — stating they are not authorized to facilitate transactions involving Anthropic stock.
According to the company, any sale or transfer of Anthropic shares conducted through these platforms “is void and will not be recognized” in the company’s official records. Anthropic emphasized that both its preferred and common stock are subject to strict transfer restrictions that require board approval before any transaction can be considered valid.
The move comes as investor demand for exposure to top AI companies continues to surge. With Anthropic reportedly seeking fresh funding at a staggering $900 billion valuation, secondary market brokers say the company has become one of the most difficult private AI stocks to acquire.
Several firms mentioned in Anthropic’s warning have pushed back against the claims. Forge Global stated that it does not facilitate private share transactions without direct approval from the issuing company and said it was working with Anthropic to remove its name from the alert.
Meanwhile, Sydecar clarified that it only acts in an administrative role and does not directly buy or sell securities. The company added that sponsors using its platform must confirm they have secured all required approvals before offering investment opportunities.
The controversy highlights growing activity in secondary AI investment markets, where investors seek indirect exposure to private companies through mechanisms such as SPVs (Special Purpose Vehicles), tokenized securities, and derivative-style investment contracts.
Anthropic specifically warned against SPVs acquiring or offering access to its shares, stating that transfers involving these structures violate the company’s transfer restrictions. The company noted that some investment opportunities marketed online may be entirely fraudulent.
The broader AI investment boom has fueled aggressive speculation across private markets as investors rush to gain exposure to companies leading the generative AI revolution. Firms such as OpenAI, Anthropic, and other major AI startups have become highly sought-after assets among venture capital firms and retail-focused secondary marketplaces alike.
Industry observers say Anthropic’s public warning signals increasing concern among private AI companies over unauthorized trading activity, investor confusion, and potential scams linked to rapidly rising valuations in the AI sector.
Author. Adigun Adedoye.