[DigitalToday reporter Jinju Hong] Generative AI startup Anthropic said it will invalidate all over-the-counter trades of its shares conducted without board approval, sending broader ripples through the private AI stock market. The move is also fuelling investor unease as the company’s valuation in the OTC market has recently surged to around $1 trillion.

Cryptopolitan, a blockchain media outlet, reported on Sunday that Anthropic said in a recent notice that any share sale or transfer without explicit board approval is void and will not be reflected in the company’s books or official records.

The measure covers not only share trades but also beneficial-interest agreements, forward contracts, special purpose vehicles (SPVs) and tokenised securities structures. Citing share-transfer restriction clauses in its articles of incorporation, the company drew a line by saying it will not recognise as official shareholder rights any stakes obtained through unapproved transaction channels.

The invalidations also include some new product trades conducted on unlisted share platforms Forge Global and Hiive. Anthropic also separately provided a list of unapproved intermediaries, including Open Door Partners, Unicorns Exchange, Pachamama, Lionheart Ventures, Sidecar and Upmarket.

The market shock is growing as it coincides with a recent surge in Anthropic’s OTC valuation. Reports said the implied valuation formed on Forge Global was about $1 trillion, exceeding OpenAI’s valuation of about $852 billion in the OTC market. Some existing shareholders were said to have sounded out an intention to sell at about $1.15 trillion through Saints Capital.

The official valuation recognised in the most recent primary investment round was about $380 billion. As the price gap between the primary market and the OTC market widened sharply, demand for indirect investment through SPVs or tokenised structures surged. Anthropic’s move effectively makes clear it will not recognise such transaction structures.

Legal circles are focusing on Anthropic’s use of the term “void”, rather than “voidable”. Cryptocurrency lawyer and MetaLeX founder Gabriel Shapiro called the policy a very strong legal measure.

He said that under Delaware corporate law, if a transaction is defined as void, it may be treated as if it never existed from the outset. In that case, subsequent buyers could find it harder to rely on legal protection arguments, and the original seller could even end up holding both cash and shares, the analysis said.

Market participants are split. Rainmaker Securities CEO Glenn Anderson said demand for Anthropic shares is very strong and some sell offers are absorbed within a day. Early investor Bradley Horowitz also said he continues to receive buy offers but has no plans to sell for now.

The industry is watching whether the move could go beyond a single company issue. Anthropic is cited as a leading unlisted AI company, along with OpenAI and SpaceX, with valuations of around $1 trillion discussed in the OTC market.

This is also raising the possibility that large unlisted AI companies could move to strengthen similar share-transfer restriction clauses or limit SPV and tokenised trades. The market is watching how far Delaware courts will recognise Anthropic’s invalidation policy and whether investor class actions will actually be filed.