3 Charts on Anthropic’s Historic IPO Filing

For three years, the stock market has been shaped by the major growth of artificial intelligence (AI). Now, Anthropic, one of the main companies in this boom, is preparing to sell shares to the public. This could be the largest initial public offering (IPO) in history. But it comes at a time when investors are questioning whether AI company stocks are worth their high prices. In particular, they are unsure whether Anthropic and other major AI companies can earn enough money to cover their huge investments in computing equipment and their financial commitments.

Anthropic filed its Form S-1 with the Securities and Exchange Commission on Oct. 26. The filing did not say how many shares the company plans to sell or what they will cost. Those details are expected in the coming weeks. However, it did give investors important information to consider before deciding whether to buy shares in the IPO. Three key areas are revenue growth, profits and free cash flow, and the use of Anthropic's products by businesses.

Here are three important things investors should look at in the S-1 filing.

Anthropic's Revenue Growth and Client Base

Anthropic's S-1 filing says that, as of Sept. 30, the company had more than 11,900 business customers that each brought in at least USD 100,000 in revenue over the previous 12 months. A year earlier, it had more than 950 customers in this group.

Malik Ahmed Khan, a senior equity analyst at Morningstar, says the filing shows that businesses are really using Anthropic's AI assistant, Claude, and that its use is growing quickly. He says, "It's pretty clear, revenue growth has been sky-high. This is the fastest scaleup of any technology business that we've seen." He also explains that business customers who spend more on software are often more likely to keep using it. However, he says Anthropic has not yet shared data showing how many customers continue to use its products over time.

The S-1 also reports a net revenue retention rate of 900%. This figure compares how much customers spent in the third quarter with how much those same customers spent a year earlier, when Anthropic earned about USD 1.4 billion per quarter. However, Rolfes says this percentage is likely to fall sharply because the earlier revenue figure was so small compared with Anthropic's current size.

Rolfes points to another measure that may better show how much more Anthropic can earn from its existing customers over time. According to the S-1, publicly traded companies in the Fortune 500 that spent at least USD 100,000 a year with Anthropic spent, on average, less than 0.1% of their total expenses on Anthropic in the third quarter. Even Anthropic's 10 biggest Fortune 500 customers spent less than 1% of their total expenses on the company, he explains. Rolfes says Anthropic could earn much more from the customers it already has if typical large customers increased their spending even partway toward those higher levels.

Anthropic's Compute Efficiency

According to the S-1, Anthropic is also earning more revenue for each dollar it spends on computing power. Khan says AI companies such as Anthropic can often grow by adding computing power more easily than by hiring more employees. He explains that quarterly revenue rose from about USD 800 million to roughly USD 12 billion, while the number of employees did not grow nearly as quickly. As a result, revenue per employee has increased greatly. It has risen to more than USD 6.6 million, compared with USD 1.4 million in September 2025.

Khan says Anthropic will need to bring more computing power into use and become better at using it if it wants to keep growing revenue. He says, "It's been very interesting and positive for Anthropic so far."

Rolfes of PitchBook says some of Anthropic's improved computing efficiency is due to when its computing costs are recorded. Companies arrange computing capacity 12–18 months in advance, but record the costs as that capacity becomes available for use, he explains. He says Anthropic's management expects its growing use of short-term computing capacity to reduce profit margins in the near future. Anthropic's agreement with SpaceXAI alone will cost about USD 3.1 billion per month when all the agreed capacity is delivered. This is expected to happen in December 2026. Rolfes calculates that this would equal roughly USD 9.3 billion per quarter, compared with total computing expenses of USD 5.6 billion in the second quarter.

Rolfes says Anthropic's computing efficiency in the second quarter of 2026 should be seen as a possible high point for its profit margins, rather than a level it can expect to maintain. He says, "Third-quarter revenue is blank in this filing, and the amendment that fills it in is the first test of that call."

Operating Efficiency and Margin Expansion

Khan explains that the S-1 shows Anthropic made an operating profit under generally accepted accounting principles (GAAP) in the second quarter. However, the company recorded an operating loss when the first half of the year is considered as a whole. Using adjusted figures, Anthropic had an operating profit margin of 19% in the second quarter.

Khan says Anthropic is also bringing in more cash than it spends on its ongoing business activities, a measure known as positive free cash flow. He says, "Anthropic has raised about USD 140 billion to date, and they still have more than USD 130 billion left. They've burned only about USD 9 billion so far." Overall, Khan says the most encouraging information in Anthropic's S-1 is its fast revenue growth, its ability to use computing power efficiently, and the amount of revenue it earns per employee.

Khan is still concerned about the company's future computing costs. He says, "A lot of Anthropic's compute costs still haven't technically come online." The company has made agreements lasting several years with Google, Amazon, and Broadcom, he explains. There is a risk that once the agreed computing capacity becomes available and the related costs begin to count, Anthropic's revenue may fall short of expectations. Even then, the company would still have to pay the commitments worth hundreds of billions of dollars.

Khan says that if Anthropic's revenue is not enough to cover these commitments, the company could return to making operating losses. He explains, "The key risk is that revenue growth doesn't turn out to be durable." Morningstar believes that AI companies such as Anthropic and OpenAI are building lasting business advantages that should help them avoid this outcome. However, Khan says this remains the biggest uncertainty.