Anthropic Series F: $13B Raise, Investors & $183B Valuation

The $13 billion round

Anthropic announced on September 2, 2025 that it had raised $13 billion in a Series F round, putting its post-money valuation at $183 billion. ICONIQ led the round; Fidelity Management & Research Company and Lightspeed Venture Partners co-led alongside it. More than a dozen other firms participated, including Altimeter, BlackRock affiliates, Coatue, General Catalyst, Goldman Sachs Growth Equity, GIC, Qatar Investment Authority and T. Rowe Price entities. [1]

Anthropic said the capital would expand its enterprise capacity, deepen its safety research and support international expansion. The same announcement disclosed that run-rate revenue had grown from roughly $1 billion at the start of 2025 to more than $5 billion by August, and that Claude Code alone had reached over $500 million in run-rate revenue after usage grew more than tenfold in three months. [1]

What it tripled from

Anthropic's prior priced round was a $3.5 billion Series E that closed on March 3, 2025, led by Lightspeed Venture Partners, at a $61.5 billion post-money valuation. Reports of that round surfaced earlier, on January 7, 2025, when Bloomberg and CNBC described Anthropic in talks to raise roughly $2 billion at a $60 billion valuation. [2][3]

Atlas interpretation: $183 billion is 2.97 times the $61.5 billion Series E close, so roughly tripling is a fair description. The eight-month span in the summary above fits better against the January 7 report of talks than against the March 3 close: close to close, Series E to Series F was six months, not eight. Either way the conclusion holds. Anthropic's valuation nearly tripled inside a single fundraising cycle, and the pace of that increase, not just its size, is the notable part. [1][2][3]

Twice more, inside a year

On November 18, 2025, Microsoft agreed to invest up to $5 billion and Nvidia up to $10 billion in Anthropic, alongside a commitment from Anthropic to spend $30 billion on Microsoft Azure compute and buy up to a gigawatt of Nvidia hardware. The deal was reported to value Anthropic in the range of $350 billion, roughly double the September figure eleven weeks earlier. [4]

That $350 billion figure was formalized as a term sheet on January 7, 2026, and the round closed on February 12, 2026 as a $30 billion Series G at a $380 billion post-money valuation, led by GIC and Coatue with D. E. Shaw Ventures, Dragoneer, Founders Fund, ICONIQ and MGX co-leading. On May 28, 2026, Anthropic closed a $65 billion Series H, led by Altimeter Capital, Dragoneer, Greenoaks and Sequoia Capital, at a $965 billion post-money valuation, citing run-rate revenue of about $47 billion. [5][6]

Atlas interpretation: Series G and Series H are the two later markups the summary above points to when it says Anthropic would do this twice more inside the following year: both closed within nine months of the Series F round, the first at roughly double the Series F valuation and the second at more than five times it. Anthropic's valuation moved from $61.5 billion to $965 billion in fourteen months. The capital driving that was tied heavily to infrastructure commitments rather than pure equity checks: Amazon, Microsoft and Nvidia each attached their investments to cloud spend or hardware allocations alongside the cash. [1][2][5][6]

Not an isolated data point

Anthropic's round did not happen in a vacuum. Seventeen days later, on September 19, 2025, xAI was reported to be raising over $10 billion at a $200 billion valuation. Four weeks after that, on October 2, 2025, OpenAI completed a $6.6 billion secondary share sale, letting employees and early investors sell existing stock, at a $500 billion valuation. [7][8]

Atlas interpretation: These figures are not fully comparable: Anthropic's and xAI's rounds were primary equity raises that put new cash on the balance sheet, while OpenAI's was a secondary sale that priced existing shares and sent no new money into the company. What the timing shows is that all three frontier labs were re-pricing within weeks of one another in fall 2025, each landing at several multiples of what it had carried a year before. Anthropic's $183 billion looked large in isolation and comparatively modest against OpenAI's contemporaneous $500 billion. That gap closed by the following spring: OpenAI reached an $852 billion valuation in a round that closed March 31, 2026, and Anthropic's $965 billion Series H, two months later, put it ahead of that figure. [6][7][8][9]