Top stories today:

1. Elon’s xAI co-founder Jimmy Ba exits as researcher departures mount
2. Isomorphic Labs unveils IsoDDE, claiming leap beyond AlphaFold 3
3. Moderna flu vaccine blocked as FDA declines review of mRNA shot
4. Sam Bankman-Fried seeks new trial, citing new witnesses in FTX fraud
5. Runway raises $315M Series E round at $5.3B valuation
6. Mistral ARR tops $400M, targets $1B by 2026
7. ChatGPT Deep Research upgraded with GPT-5.2, site-focused reports

0. Data and calendar

Listen to our AI-generated podcast summarizing today’s newsletter (beware of hallucinations):

1. Elon’s xAI co-founder Jimmy Ba exits as researcher departures mount

• Ba becomes the 6th founding member to leave xAI

• Likely connected to vesting of xAI stock given its sale to SpaceX.

• Mon.: Tony Wu became the 5th founder to exit the 12-person team that launched xAI in 2023.

• 6+ xAI researchers have left in recent weeks, per sources and social posts.

• Anthropic is the only major AI lab that has retained all its (7) co-founders.

• Tue.: Elon Musk held a staff call to discuss changes in technical leadership.

• Leadership overpromised progress to Musk as xAI raced to catch OpenAI and Anthropic, some employees reportedly said.

2. Isomorphic Labs unveils IsoDDE, claiming leap beyond AlphaFold 3 in drug design

On the Runs N’ Poses benchmark, IsoDDE more than doubles AlphaFold 3’s accuracy on the hardest cases:

IsoDDE outperformed AlphaFold 3 by 2.3× and Boltz-2 by ~20× on high-fidelity antibody–antigen predictions

4. Moderna flu vaccine blocked as FDA declines review of mRNA shot