Question
Will Anthropic's first day of public trading occur before OpenAI's first day of public trading?
Summary Anthropic is currently positioned as the favorite to list publicly before OpenAI, despite OpenAI having confidentially filed its S-1 with the SEC slightly earlier. OpenAI filed around May 20-22, 2026, but its subsequent public messaging on June 8 explicitly signaled a delay, noting that an IPO "may be a while" as the company works on objectives that are easier to accomplish while private 2 sources. Furthermore, evidence suggests internal tension at OpenAI regarding readiness, with CFO Sarah Friar reportedly pushing for a 2027 timeline rather than an immediate debut 2 sources. In contrast, Anthropic, which filed its confidential S-1 on June 1, 2026, appears to be moving purposefully toward a fall 2026 listing, potentially in October or November 2 sources. While OpenAI's earlier filing grants it a slight procedural head start, Anthropic's unified approach and stronger recent financial metrics ($47 billion revenue run rate and $965 billion valuation) provide a tangible momentum advantage 2 sources. Market sentiment strongly favors Anthropic crossing the finish line first 2 sources. However, the unprecedented scale of both companies guarantees intense regulatory scrutiny, creating a realistic possibility of prolonged SEC reviews. The resolution criteria strictly require Anthropic to list on an earlier calendar date; if OpenAI lists first, if both list on the same day, or if neither lists by December 31, 2027, the outcome is negative. Accounting for these edge cases—particularly the non-trivial risk that a closing IPO window or regulatory hurdles push both listings past 2027—tempers the probability, keeping the final assessment in the low-to-mid 60s.
Strongest Arguments for Yes
- OpenAI's own public statements have tempered expectations for a rapid debut; their June 8 announcement explicitly stated "it may be a while" 2 sources.
- Internal dynamics at OpenAI reveal caution among financial leadership, with CFO Sarah Friar warning that a 2026 IPO timeline is too aggressive due to spending commitments and missed revenue targets, favoring a 2027 listing instead 2 sources.
- Anthropic demonstrates no reported internal friction regarding its IPO timing and is operating with apparent urgency, targeting a debut as soon as October or November 2026 3 sources.
- Anthropic boasts stronger immediate financial metrics, including a $47 billion revenue run rate and a recent $965 billion valuation, potentially smoothing its path to market compared to OpenAI's $25 billion run rate and $852 billion valuation 2 sources.
Strongest Arguments for No
- OpenAI confidentially filed its S-1 with the SEC around May 20-22, 2026, approximately 10 days before Anthropic's June 1 filing 2 sources. This procedural head start gives OpenAI an advantage on the standard 90-150 day SEC review clock dart.deloitte.com.
- OpenAI CEO Sam Altman has a documented track record of pushing through ambitious timelines and has targeted a September 2026 listing, which is earlier than Anthropic's October target 2 sources.
- Strict resolution criteria dictate that if neither company begins public trading by December 31, 2027—a realistic scenario if the IPO window closes or regulatory friction is severe—the outcome will be negative 2 sources.
- OpenAI's cautious public messaging could be strategic misdirection, allowing the company to quietly advance its SEC review process and flip its S-1 public before Anthropic axios.com.
Key Uncertainties
- Internal Leadership Dynamics at OpenAI: It remains uncertain whether CEO Sam Altman's aggressive push for a September 2026 listing will override CFO Sarah Friar's strong preference to delay the IPO until 2027 2 sources. If Altman prevails, OpenAI could leverage its SEC head start to list first, decreasing the probability; if Friar's caution wins out, Anthropic's path to listing first is virtually assured.
- SEC Scrutiny and Regulatory Timelines: Given the massive valuations and novel nature of these AI giants, the SEC review process could be highly unpredictable dart.deloitte.com. If Anthropic faces disproportionate regulatory pushback, OpenAI could close the gap; conversely, smooth sailing for Anthropic would cement its lead. Severe delays for both would increase the likelihood of neither listing by December 2027.
- Broader AI Market Conditions: A robust IPO market would encourage both companies to race toward their fall 2026 targets, maintaining Anthropic's slight edge axios.com. However, a downturn in AI sentiment or a closing of the broader IPO window could force both companies to delay going public until after December 31, 2027, resulting in a negative outcome 2 sources.