Anthropic expanded a ban on secondary-market methods for buying its private shares this month, causing a sharp drop in tokenized-share prices [1].

The move disrupts the "shadow IPO" market where investors trade stakes in high-value private companies before they go public. By restricting these transfers, Anthropic is attempting to maintain control over its private-market valuation and prevent unauthorized ownership changes.

The company said around May 13 that certain structures used to facilitate these trades may be invalid [1]. Specifically, the ban targets Special Purpose Vehicle (SPV) structures, which are often used to bundle shares for smaller investors. This warning sent a jolt through global investor networks, including X, Reddit, and various Chinese-language platforms [2].

On the Solana blockchain, tokens that claim to track the private-market valuations of Anthropic and OpenAI dropped nearly 40% following the warning [1]. The volatility spilled over into private communication channels, including a WhatsApp family-office chat with several hundred members [2].

"Are we screwed?" one anonymous participant in that WhatsApp group asked [2].

Despite the panic in some circles, other market indicators suggest continued high demand. Some reports indicate the shadow market for Anthropic is still flashing trillion-dollar prices [3]. However, the company's decision to invalidate SPV transfers creates significant legal and financial uncertainty for those holding these synthetic assets.

Anthropic said the measures are necessary to ensure that transfers of its shares are authorized and valid [1].

“Tokens on Solana that claim to track the private-market valuations of Anthropic and OpenAI dropped sharply”

This crackdown highlights the growing tension between the massive public appetite for AI equity and the strict governance requirements of private companies. By invalidating SPV-backed tokens, Anthropic is signaling that it will not tolerate 'synthetic' liquidity that allows the public to speculate on its valuation without direct corporate oversight.