Anthropic on Monday filed highly anticipated paperwork (opens in new tab) to go public, in what could be the largest listing in history, generating a tidal wave of wealth in San Francisco, where the company was founded and is based.
The company will use the ticker symbol ANT on the Nasdaq stock exchange. Its CEO and founders together will hold 50.1% of the company’s voting power. The S-1 filing revealed that Anthropic lost $80 billion in the first half of 2026, much of that due to accounting adjustments tied to its growing valuation. Operating loss for that period was $693 million, and revenue was $16.3 billion, a major leap from $1.16 billion in the same period the year before.
The maker of Claude has quickly risen to prominence, with AI models that have revolutionized coding and changed how people around the world work. It has its hands in city culture, state laws, and national politics, and the IPO should only expand its influence. The public listing has ripple effects across San Francisco, creating a class of millionaires and billionaires made up of Anthropic employees.
The executive team — a group of safety-focused AI engineers who left rival OpenAI — have said their technology is so powerful it could end humanity. Those warnings give them a powerful voice in public policy and private industries, likely helping the company valuation. In May, the last time Anthropic raised money in the private market, investors valued (opens in new tab) the company at $965 billion.
A significant portion of the IPO paperwork discusses risk factors to success. Anthropic repeated many of its past warnings, saying its advanced AI models “have been, and may continue to be, misused or manipulated to produce harmful outputs or carry out harmful actions.” It specifically mentions concerns about malicious actors using Anthropic’s AI tools to create chemical, biological, and other weapons. Those are just some of the bigger concerns, and the document gets into many smaller ones.
“Advanced AI models, including our models, give rise to novel ethical and safety risks, including risks related to autonomy, manipulation, and the simulation of aspects of human psychology,” the document notes.
Other risk factors include falling behind competitors; insufficient electrical power; loss of talent, especially at the executive level; and demand for AI that doesn’t develop quickly enough.
Economists say the AI boom is already affecting San Francisco, mainly through more jobs and increased rents. Exactly how much wealth the city will see from the IPO will depend largely on the stock’s performance overall and less on details like how long employees must wait before they are allowed to sell their shares, known as a “lockup period,” according to the city’s chief economist, Ted Egan. Some money could end up in city coffers when the employees start spending, in the form of property taxes when they buy homes and as higher business taxes tied to stock compensation.
The waiting period for selling stock won’t be the same for everyone, according to Anthropic’s filing. While investors who buy shares in the IPO can usually sell immediately, directors and executives who aren’t founders, along with certain employees, face restrictions. Some shares will be eligible for sale starting 27 days after the prospectus date; others will be at set intervals over the following months. For Anthropic’s founders, the wait is longer. With limited exceptions, they must wait up to six months to sell up to 29% of their shares and up to a year to sell the rest.
Each of the seven founders has roughly 240 million shares, likely worth billions. At the company’s founding, the cofounders pledged 80% of their equity to charity. The latest filing, however, allows room to abandon those promises. “These commitments are voluntary, revocable expressions of each co-founder’s philanthropic intent and do not constitute legally binding obligations,” the document says.
The company continues to operate a donation matching program for employees. Anthropic donates three shares of non-voting stock to approved charities when eligible employees hired more than two and a half years ago donate one share. It gives one matching share per each donated by newer employees. In August, its employees donated shares through the program and as a result, the company added $2 billion in operating expenses in the third quarter and issued roughly 28 million new shares. It’s unclear how much went directly to charities.
The company is leasing its Financial District headquarters — 300 and 342 Howard Street — for 12 years, a deal valued at $200 million.
Anthropic did not say what date it will start trading, how many shares it plans to sell, or what the offering price will be. However, it could go public as soon as mid-November.