Anthropic IPO Filing Warns of Uninsurable Catastrophic AI Incident as
Anthropic IPO Filing Warns of Uninsurable Catastrophic AI Incident as Founders Keep Tight Grip on Claude Maker

Anthropic, the artificial intelligence company behind the Claude chatbot, moved ahead on Monday with plans for a blockbuster initial public offering. It made public a filing that details its rapid growth, enormous computing bills and a governance structure that will leave its founders and an independent trust firmly in control after it lists.

The registration statement on Form S-1, filed with the U.S. Securities and Exchange Commission, shows Anthropic plans to list its Class A shares on the Nasdaq Global Select Market under the ticker "ANT." The company could begin trading as early as the week before Thanksgiving, according to media reports.

Anthropic did not disclose a target valuation, the number of shares it plans to sell, or a price range. Those fields were left blank in the filing. Media reports have put a possible valuation between $1.5 trillion and $2 trillion, which would make it one of the largest market debuts on record.

Goldman Sachs and Morgan Stanley lead a group of 22 underwriters on the deal.

94 pages of risks

The filing's risk factors section runs about 94 pages, covering threats ranging from competition and computing costs to the behavior of the company's own AI systems.

Among the most striking is a warning about a "catastrophic AI-related incident." According to The Wall Street Journal, Anthropic said the damages from such an event could be so large that it could not obtain insurance to cover them.

In its summary of risk factors, the company wrote that "our AI models may behave in unintended, misaligned, or autonomous ways, including by taking harmful actions," and that "our contractual protections and insurance may be insufficient."

The filing also says some models have shown "self-preserving" behavior to avoid being shut down, according to reports on the document.

Anthropic also warned investors not to expect its recent pace of growth to last. "We do not expect our revenue will continue to grow at comparable rates," the company wrote. That caution appears in a filing that elsewhere describes Claude as having "the fastest enterprise adoption of any technology in history."

Other risks include political opposition to data center construction, which the company said has "become more organized and coordinated across jurisdictions," and dependence on a "limited number of customers for the foreseeable future," according to reports.

Founders and trust in control

Investors buying shares in the IPO will have limited say over how the company is run.

The filing describes several classes of stock:

  • Class A: The shares sold to the public, with one vote each.
  • Class F: A single share held by a limited liability company whose members are initially the seven co-founders. It carries "50.1% of the total voting power" on most matters put to stockholders.
  • Class T: Held by the Long-Term Benefit Trust, a body of five financially disinterested trustees. The trust "generally has the authority to elect and remove the Class T directors," who will make up a majority of the board.
  • Class N: Held largely by strategic partners, with no voting rights except where required by law. These shares generally convert to Class A when sold to an unaffiliated buyer.
  • Class E: Held by non-founder employees, with voting rights on a narrow set of issues.

The founders in the LLC are Chief Executive Dario Amodei, President Daniela Amodei, Tom Brown, Jack Clark, Jared Kaplan, Sam McCandlish and Christopher Olah, according to reports on the filing.

The structure includes a sunset provision. If fewer than three founders remain in the LLC for 90 consecutive days, a 450-day transition period begins, after which the Class F and Class E shares are redeemed for nothing.

Because the trust can elect a majority of the board, Anthropic will qualify as a "controlled company" under Nasdaq rules. It said it would use that exemption only for its nominating and governance committee. Anthropic is organized as a public benefit corporation, which requires it to weigh a stated public mission alongside shareholder returns. The company also said it plans to commit 5% of its shares to a public benefit fund.

Revenue soars, losses balloon

According to the filing:

  • Revenue for the first six months of 2026 rose to $16.3 billion, from about $1.2 billion a year earlier.
  • The net loss was $80.7 billion. About $72.4 billion of that came from accounting changes in the fair value of convertible notes and similar instruments, driven by the company's rising valuation.
  • The operating loss narrowed to $693 million, and adjusted operating income was $1.6 billion.
  • More than 1,900 customers had each paid at least $1 million over the 12 months to Sept. 30, and about 250 had paid $10 million or more.
  • Cloud marketplaces run by partners such as Amazon, Google and Microsoft accounted for about 48% of revenue, even though those companies also sell competing AI models.

Anthropic has raised a total of $141.1 billion and held about $112.4 billion in cash at the end of June.

The company has also made huge computing commitments. According to reports on the filing, its contracted obligations for computing capacity exceed $600 billion, including long-term, noncancelable cloud contracts payable "regardless of actual usage."

The company said it plans to use the offering's proceeds "for general corporate purposes."

Markets weigh AI and Brazil

The filing landed on a busy day for global markets. U.S. stocks rose modestly in early trading, though investors kept scrutinizing the AI trade after concerns about the cost and financing of AI spending weighed on technology shares last week.

Brazilian assets tumbled after President Luiz Inácio Lula da Silva unexpectedly won re-election on Sunday, defeating Flávio Bolsonaro in a runoff. The real slid sharply against the dollar, and U.S.-listed shares of Brazilian banks and oil company Petrobras plunged in premarket trading.

"Lula's victory should trigger disorderly moves in local markets," Barclays analysts wrote in a note.

William Jackson of Capital Economics said the result "will dash hopes for reforms."

Oil prices slipped on hopes of easing tensions between the U.S. and Iran. Brent crude fell to about $115 a barrel.

Investors are also preparing for the Federal Reserve's interest rate decision on Wednesday and earnings this week from Alphabet, Microsoft, Amazon and Meta Platforms. Their AI spending plans will be closely compared with the figures disclosed in Anthropic's filing.