Anthropic will end Sonnet 5's promo on schedule and charge full price — resolves 2026-09-15

The debate: investor Bill Gurley argued that no AI lab dares to raise prices, because each is afraid of losing market share; our 2026-08-16 column said the opposite, that the big labs already have pricing power.

Why it matters: if labs can raise prices, companies building on these models should budget for rising unit costs rather than assume prices only fall.

Who is on each side: Gurley and the price-war camp expect promotions to be extended and prices to keep sliding; the pricing-power camp, our column included, expected Anthropic to let the Sonnet 5 promotion lapse on schedule.

The most direct test of Bill Gurley's claim that no one dares to raise prices — that Anthropic, afraid of losing market share, will not touch its price: Anthropic's official pricing page says the Claude Sonnet 5 promotional price ends on 2026-08-31. Does the price go back to the standard rate on September 1, a 50% increase?

BG2 Pod (Brad Gerstner + Bill Gurley)
“companies are not pricing the cost... no one's…”

After 2026-09-01, check Anthropic's official pricing page (platform.claude.com/docs/en/about-claude/pricing) directly. If Sonnet 5 shows the standard price, the terms were carried out and this issue's call that Gurley's claim does not hold gets its strongest piece of evidence. If the promotion is extended, or the standard price itself is cut, the terms were not carried out.

Miss (settled 2026-09-30)

The prediction: Anthropic would let the promotional price for its Claude Sonnet 5 model end on schedule on August 31 and charge the standard price from September 1, taking the price per million input and output tokens from $2 and $10 back to $3 and $15, a 50% increase. It was the most direct test of whether the big AI labs dare to raise prices. How it would be checked, decided when the prediction was made: after September 1, look at Anthropic's official pricing page. The standard price means the prediction was right; an extended promotion, or a cut to the standard price itself, means it was wrong. On 2026-09-30 the official pricing page said the promotional price had become the standard price and that the planned September 1 increase was cancelled. Anthropic did not raise the price, so the prediction was wrong. The check was due by September 15, a date set when the prediction was made, and came 15 days late. Related correction: an opinion column we published on August 16 had ruled that investor Bill Gurley's claim, that AI companies are too afraid of losing market share to raise prices, did not hold, and this expected increase was its strongest evidence. With the increase cancelled, on October 3 we changed that ruling from "does not hold" back to "undecided" (meaning it is too early to say whether Gurley is right), and added a note at the top of the column and of our August 16 daily newsletter in Chinese, English and Japanese. A second condition was also agreed in advance: if, in the same period, the price of the most advanced model fell by half or more and no pricier option appeared above it, that would mean AI model prices overall were quietly falling. That did not happen: a new, more expensive price level was added in the same period, so the idea that prices were quietly falling found no support.

Evidence used to settle it

platform.claude.com · checked 2026-09-30
“The $2/$10 per million input/output token pricing for Claude Sonnet 5, announced at launch as introductory pricing through August 31, 2026, is now the standard price. The previously scheduled increase to $3/$15 … on September 1, 2026 will not occur.”