Which completes IPO first before Dec 31, 2027 11:59 PM ET: Anthropic or OpenAI?

Earlier updates

1. Sep 21, 2026 UTC — Anthropic's IPO timeline faces conflicting signals, weakening its lead.; Conflicting reports emerged this period regarding Anthropic's IPO timeline. One source indicates a target window before the November US midterm elections, while another suggests a potential delay until after the elections. Meanwhile, OpenAI's IPO remains slated for 2027, with its CEO explicitly citing AI safety concerns for the postponement. The uncertainty in Anthropic's internal timeline weakens its previously clear first-mover advantage over OpenAI.
2. Sep 22, 2026 UTC — Anthropic's IPO timeline faces new uncertainty, further weakening its lead.; This period saw new conflicting signals regarding Anthropic's IPO timeline. While earlier reports suggested a target listing as early as October, new reports citing sources indicate its IPO may be delayed until after the US midterm elections. This potential delay conflicts with the earlier expectation, adding uncertainty to its timeline. Meanwhile, OpenAI's IPO plan remains set for 2027, with its CEO explicitly citing AI safety concerns for the postponement. The uncertainty in Anthropic's internal timeline has weakened its previously clear first-mover advantage over OpenAI.
3. Sep 23, 2026 UTC — Anthropic's IPO timeline has been pushed further to November, narrowing its first-mover advantage window over OpenAI.; During this period, multiple media reports have confirmed that Anthropic's IPO timeline has been pushed from October to November. Reasons cited include waiting to release third-quarter financial results to demonstrate competitiveness and responding to market momentum following OpenAI's GPT-6 Astra launch. Some sources even mentioned a potential delay until after the U.S. midterm elections. This wave of reports reinforces the uncertainty in Anthropic's listing timeline, and its clear lead over OpenAI is diminishing. Meanwhile, OpenAI's IPO plan remains locked in for 2027, with its CEO's stance on delaying due to AI safety concerns unchanged.
4. Sep 24, 2026 UTC — Anthropic's IPO timeline has been pushed further to November, narrowing its first-mover advantage window over OpenAI.; Multiple media outlets have confirmed this period that Anthropic's IPO timeline has been pushed from October to November. Reports cite reasons including waiting to release Q3 financials to demonstrate competitiveness and countering market momentum from OpenAI's GPT-6 Astra launch. Some sources even mention a possible delay until after the US midterm elections. This wave of reporting reinforces the uncertainty in Anthropic's listing timeline, and its clear lead over OpenAI is narrowing. Meanwhile, OpenAI's IPO plan remains locked in for 2027, with no change in its CEO's stance on delaying a public offering due to AI safety concerns.
5. Sep 25, 2026 UTC — Anthropic's IPO timeline has been pushed further to November, narrowing its first-mover advantage window over OpenAI.; Multiple media outlets have confirmed this period that Anthropic's IPO timeline has been pushed from October to November. Reports indicate the delay is to allow the company to release Q3 financials to demonstrate competitiveness and to counter market momentum following OpenAI's GPT-6 Astra launch. Some sources even mentioned a potential delay until after the U.S. midterm elections. This wave of reporting reinforces the uncertainty in Anthropic's listing timeline, and its clear lead over OpenAI is narrowing. Meanwhile, OpenAI's IPO plan remains locked in for 2027, with no change to its CEO's stance that the listing is delayed due to AI safety concerns.
6. Sep 26, 2026 UTC — Anthropic's IPO timeline remains in the November window, but the possibility of a delay until after the midterm elections is cited by more sources, increasing uncertainty.; During this period, new reports on Anthropic's IPO timeline were limited, largely continuing the previous narrative of a delay to November. Cailian Press and several AI news roundups mentioned that Anthropic may postpone its IPO until after the U.S. midterm elections in November, a claim repeated across multiple sources, reinforcing the uncertainty of its listing timeline. Meanwhile, although there were financial reports about OpenAI's massive cash burn, there was no update on its CEO's previous statement about delaying the IPO to 2027, leaving its timeline unchanged. Overall, Anthropic's first-mover advantage window over OpenAI still exists, but the timing has become more ambiguous.
7. Sep 27, 2026 UTC — Anthropic's IPO timeline remains in the November window, but the possibility of a delay until after the midterm elections is cited by more sources, increasing uncertainty.; New reporting on Anthropic's IPO timeline was limited this period, largely extending the prior narrative of a delay to November. Cailian Press and several AI news roundups all mentioned that Anthropic may further postpone its IPO until after the U.S. midterm elections in November, a claim repeated across multiple sources, reinforcing the uncertainty around its listing timeline. Meanwhile, although there were financial reports on OpenAI's massive cash burn, its CEO's previous statement delaying the IPO to 2027 remained unchanged, with no material shift in its listing schedule. Overall, Anthropic's first-mover advantage window over OpenAI persists, but the timing has become more ambiguous.
8. Oct 12, 2026 UTC — Anthropic's IPO timeline still points to late October or November, but the possibility of a delay until after the midterm elections continues to be cited, keeping uncertainty elevated.; Only one directly relevant report arrived this period, from an X user, explicitly stating Anthropic's IPO is set for late October or November, consistent with the prior November window narrative and representing no substantive change. The source is a personal account with limited authority, and it does not address the midterm election factor, so it does not resolve the delay possibility raised by multiple earlier sources. No new reports on OpenAI arrived, leaving its 2027 timeline unchanged. Overall, Anthropic's first-mover window relative to OpenAI remains, but the exact timing stays uncertain.
9. Oct 13, 2026 UTC — Anthropic's IPO timeline still points to late October or November, but the possibility of a delay until after the midterm elections continues to be cited, keeping uncertainty elevated.; The only directly relevant report this period came from Similarweb on X, showing Claude's website monthly visits surpassed 1 billion for the first time in September 2026, with a mention of Anthropic's anticipated IPO. The report confirms Anthropic's IPO plans remain on track but provides no specific timing and does not address midterm election factors, so it cannot further resolve the delay possibility raised by earlier sources. No new reports on OpenAI emerged, leaving its 2027 timeline unchanged. Overall, Anthropic's first-mover window relative to OpenAI remains intact, but the exact timing is still uncertain.
10. Oct 14, 2026 UTC — Anthropic's IPO timeline still points to late October or November with delay risk cited, while OpenAI faces a new legal challenge that has not altered its 2027 IPO plans.; The only directly relevant report this period comes from Bloomberg, covering Apple's request for a federal judge to bar OpenAI from using hardware secrets allegedly taken by a former employee. The report explicitly notes OpenAI is preparing an IPO at a $1.4 trillion target valuation, confirming its process is advancing, though the legal dispute introduces a new source of uncertainty. No new reports arrived on Anthropic; the earlier Similarweb data showing Claude's monthly visits surpassing 100 million still indicates its IPO plans are progressing, but no timeline update was provided. Overall, Anthropic's first-mover window relative to OpenAI remains, but OpenAI's legal risk has not yet altered its 2027 schedule.
11. Oct 15, 2026 UTC — Anthropic's IPO timeline still points to November, though slowing growth has sparked valuation downgrade talk; OpenAI has no new reports and its 2027 IPO plans remain unaffected.; Anthropic dominated this period as multiple outlets reported Q3 revenue of $16.8 billion, with quarter-over-quarter growth slowing from 147% to about 45%. Bloomberg reported bankers had floated a roughly $2 trillion IPO valuation with plans to raise over $100 billion, but The Decoder cited investor disappointment and projected the valuation could fall below $1.5 trillion. Bloomberg's Asia market report said these results should support an IPO before year-end, while also noting the market read the slowdown as negative for the AI chip sector. OpenAI had no new reports, and the earlier Apple lawsuit legal risk did not escalate further. Overall, Anthropic's November IPO window remains intact, but valuation expectations face downward pressure.
12. Oct 16, 2026 UTC — Anthropic's IPO timeline still points to November, but valuation expectations have been cut from ~$2 trillion to $1.5 trillion, and New York City's comptroller has publicly urged a delay, raising near-term uncertainty.; This period saw concentrated reporting on Anthropic's valuation downgrade. Reuters, citing sources, said investors are tempering IPO valuation expectations due to slowing revenue growth; Bloomberg and multiple outlets put the figure at ~$1.5 trillion, down from ~$2 trillion. Separately, New York City's comptroller asked Anthropic to delay its IPO over safety concerns, calling a White House 'morally binding' agreement insufficient. Tech stocks fell amid doubts over AI spending and Anthropic's valuation, souring sentiment. Still, Bloomberg's Asia desk said results should support an IPO before year-end, so the November window remains open.