Anthropic’s S-1, by the numbers: A thriving business - with a $441 billion asterisk

Around 9 AM on October 26, Anthropic unveiled one of the most eagerly awaited documents in Big Tech history, its prospectus for an initial public offering. Now that the Claude purveyor has filed its S-1 with the SEC , it’s free to begin a roadshow in 15 days, and pursue a timetable that would see its shares trading on the Nasdaq, under the symbol ANT, as early as mid-November. At an anticipated valuation in the $1.8 to $2.0 trillion range, Anthropic would rank second only to SpaceX as the largest market debut of all time.

Given its central importance both as a potential investment and bellwether for the future of AI, Wall Street research crews and everyday investors alike are carefully parsing the over 400 page document. And one big concern dwarfs all others: Can Anthropic generate revenues so gigantic that they far outpace the huge spending on compute its leaders already acknowledge is coming? Evidence that’s happening would provide much comfort before folks and funds wrestle with the next and more vexing head-spinner: Will any reasonable projections for its growth in sales and operating leverage prove great enough to make Anthropic worth anything like $2 trillion?

So far, the S-1 shows surprisingly excellent bedrock performance, and boasts great financial strength. On the potential downside, it’s committed to big spending on AI capacity that it can’t cancel, meaning that the expenses are locked in while the sales are far less certain.

Let’s start with the positive operating news. For the first six months of 2026, revenues exploded 13x from $1.3 to $17 billion over the same period last year. But a big surprise comes from disentangling the income statement. Under GAAP, Anthropic suffered a staggering loss of $80 billion in the first half of 2026. But the vast bulk of that paper deficit arose from changes in fair value of convertible notes. Back out that non-cash charge and several others including equity compensation, and Anthropic actually garnered adjusted operating income of $1.6 billion for the first six months of 2026, for a 9%+ margin.

So far, the cash flow scenario also looks favorable. For first half 2026, Anthropic collected $3.93 billion in cash from operations. Its capex, the item that’s mushrooming at SpaceX, was so tiny this writer did a double take: Less than $500 million. As a result, Anthropic registered positive free cash flow of around $3.5 billion.

Operating leverage, the ability to expand margins by growing revenues faster than costs, is also pointing the right way. Specifically, top-line growth is outpacing the expense of the data center capacity that runs Claude, Fable, and Mythos. In Q1, sales exceeded AI infrastructure costs by 40%. In Q2, it was more than double, $11.6 billion in revenues versus $5.6 billion for compute. Customer stats are also impressive. The S-1 disclosed that Anthropic now harbors a base of 11,000 enterprises featuring over $100,000 a year in revenue, up from 1,500 last year.