Anthropic Weighs Lockup Beyond 180 Days to Curb IPO Selling

Anthropic is weighing insider lockup periods that stretch beyond the conventional 180 days, an unusual safeguard for a debut that could rank among the largest ever attempted.

The company may choose not to lock up a portion of insider shares, people familiar with the matter said, in a departure from the standard six-month restriction that lets early investors and employees sell once it lapses. Lockup expirations can put downward pressure on a stock as fresh supply hits the market, and Anthropic's decision could reshape how tech companies handle insider restrictions as part of an IPO.

Anthropic is expected to begin marketing the offering in mid-October at the earliest and complete the listing days before the U.S. midterm elections in November, the people said. The prospectus, initially expected as early as next week, is now not expected until late September. Morgan Stanley, Goldman Sachs, JPMorgan and Citi are among the banks working on the deal, and the company is finalizing a $15 billion revolving credit facility.

The stakes are unusually high. Investors have floated a $2 trillion valuation for Anthropic, which would rank among the largest IPOs ever attempted and value the developer of the Claude chatbot at roughly 30 times revenue. That compares with SpaceX, which went public in June at a record $1.77 trillion valuation, or about 100 times sales.

The lockup math matters because history is unforgiving for mega-cap debuts. According to FactSet data, only nine of the 36 companies with market caps above $15 billion that listed on major U.S. exchanges have outperformed the S&P 500 since their IPO. Lockup expirations and slower-than-expected growth have contributed to the lackluster record. The pattern is familiar from the last wave of high-profile tech listings, where several stocks gave back their opening gains once insider restrictions lapsed and a wave of shares hit the market.

Anthropic's growth is the counterweight. Its annualized revenue run rate reached $65 billion at the end of July, up from about $9 billion at the end of 2025 — a ninefold increase in a year — and the company posted its first operating profit in the second quarter. It projects 2028 revenue of $190 billion to $200 billion, roughly triple July's annualized level, which would put a $2 trillion valuation at about 10 times 2028 revenue. SpaceX, by contrast, posted a $541 million net loss in the second quarter even as its revenue grew 92 percent year over year.

A longer lockup would shrink the supply of shares available for insider selling after the debut, supporting a steadier price trajectory and showing management's confidence in the stock. But it also ties up early investors' capital for longer, a trade-off that could shape how the deal is received. If Anthropic extends the restriction, it may set a template for other AI listings, including a potential offering from OpenAI, as the sector's biggest names test public-market appetite for a rapidly growing industry. The decision, expected to be finalized as the prospectus nears publication in late September, will be one of the first signals of how Anthropic plans to manage the transition from private to public ownership.

This article is for informational purposes only and does not constitute investment advice.