Anthropic, the AI company behind Claude, is warning investors that tokenized products claiming to offer access to its private shares may be invalid, escalating a fight over whether restricted pre-IPO stock can be repackaged for retail traders.

In an updated investor-warning page first published in February, Anthropic said any unapproved sale or transfer of its stock, or any interest in its stock, is void and will not be recognized on its books.

"We do not permit special purpose vehicles (SPVs) to acquire Anthropic stock and any transfer of shares to an SPV are void under our transfer restrictions. Offers to invest in Anthropic’s past or future financing rounds through an SPV are prohibited," the company wrote on an updated warning page. "This means that if someone purports to sell Anthropic shares without proper board approval, that transaction is invalid."

It added that any third party claiming to sell Anthropic shares to the general public through direct sales, forward contracts, "tokenized securities," or other mechanisms is likely either engaged in fraud or offering an investment that may have no value due to our transfer restrictions.

Over the past year, several crypto exchanges have set up offerings for pre-IPO exposure to some of the hottest tech companies on the planet, such as Anthropic, SpaceX, and Polymarket. However, not all offerings are the same.

Some are synthetic pre-IPO perpetuals, where no underlying shares are necessarily held, and traders are simply betting on a reference price tied to a private company’s implied valuation. Those instruments may not directly violate a company’s stock-transfer restrictions because no shares move, but they leave users with a derivative claim rather than equity exposure.

By contrast, products offering private market exposure through special purpose vehicles (SPVs) or secondary-market holdings, such as PreStocks’ tokenized single-asset offerings or the Robinhood Ventures Fund I, are closer to tokenized private-share exposure.

PreStocks’ terms of service state that buyers receive no equity or shareholder rights in the underlying company, only economic exposure tied to reserve backing, However, it does not specify whether this exposure is delivered through a special purpose vehicle, leaving uncertainty around the exact structure behind its Anthropic-linked tokens, which the company says may be invalid.

That model may be more intuitive to investors, but it also runs more directly into the restrictions private companies place on who can buy, sell or hold interests in their stock.

John Montague, a Florida-based crypto lawyer, previously told CoinDesk that private companies may challenge these structures.

“I think private companies may also initiate lawsuits alleging that this violates their governance documents, shareholders' agreements, investor rights agreements, or bylaws,” he told CoinDesk last year. "I view it as the issuer’s right to control the terms of transfer."

Aside from unauthorized stock transfers, another headache these markets create for companies is valuation. Tokenized markets can generate eye-popping implied price tags that appear to be legitimate public price discovery, even when the underlying liquidity is relatively small.

PreStocks’ dashboard recently showed that Anthropic had an implied valuation above $1.5 trillion and a market valuation of around $1.37 trillion, despite the platform holding roughly $23 million in total assets.

For private companies that raise capital through negotiated funding rounds rather than public markets, this creates a real narrative risk. Speculative token prices can begin to shape investor expectations and headlines about valuations beyond the company's control.