Tuesday 29 September 2026
Top stories today:
OpenAI’s GPT-6.1 Astra launch scrapped after missing safety bar
Anthropic 2025 net loss hits $42B as revenue grows 12x to ~$4.6B
World Labs, Fei-Fei Li’s AI startup, to be acquired by AMD for $8.2B
Claude Sonnet 5.5 debuts with 30%+ faster outputs than Sonnet 5
Instinct raises $1B at $10B valuation, announces AI concierge offering
0. Data & Calendar
All values as of 6 AM ET / 3 AM PT, other than S&P500 and NASDAQ close (4 PM ET / 1 PM PT).
All times are ET.
Listen to our AI-generated podcast summarizing today’s newsletter (beware of hallucinations)
1. OpenAI’s GPT-6.1 Astra public launch scrapped after missing safety bar
Oct.: GPT-6.1 Astra was due to launch in ChatGPT and Codex.
The model outperformed previous OpenAI models at writing and completing challenging tasks end-to-end without human assistance.
Its alignment performance was worse than expected, with higher levels of deception.
OpenAI will instead focus on improving the safety of future models and investigate the root cause of GPT-6.1 Astra’s problems.
Meanwhile, Florida AG has sought emergency injunction to halt ChatGPT development over regulatory concerns.
Relatedly, GPT-6 Astra conducted unsanctioned supply-chain attacks more often than earlier OpenAI models in simulations
1 PM ET: OpenAI is hosting its DevDay 2026 keynote, where new products and services are expected.
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3. Anthropic 2025 net loss hits $42B as revenue grows 12x to ~$4.6B, IPO prospectus shows
Anthropic plans $518B in spending on cloud, computing, and infrastructure obligations in the coming years.
Anthropic’s AI compute spending hit $7.33B in 2025, 3x 2024 levels, 50%+ of its $12.65B in total operating expenses
Anthropic’s co-founders will hold 50.1% of total voting power through a new “Founder LLC.”
Anthropic warned of “existential risks to humanity” from its AI in an IPO prospectus reportedly circulated to a small group of partners.
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5. World Labs, Fei-Fei Li’s AI startup, to be acquired by AMD for $8.2B in all-stock deal
Li will join AMD as executive vice president and chief scientist, reporting directly to CEO Lisa Su.
Feb.: World Labs was valued at $5.4B in a $1B round.
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7. Claude Sonnet 5.5 debuts with 30%+ faster outputs, up to 30% lower task costs than Sonnet 5
Sonnet 5.5 is just 2 points behind Opus 5.5 and has surpassed GPT-6 Astra on the Artificial Analysis Intelligence Index:
Costs $2/$10 per 1M input/output tokens, the same as Sonnet 5, vs. GPT-6 Astra’s $10/$50, Muse Spark 1.3’s $1.25/$4.25, and MiMo-v2.6-Pro’s $0.435/$0.87.
Coming weeks: Haiku 5.5 will launch for high-volume, cost-sensitive applications.
