Alan Ding from Thrive Capital and OpenAI co-led a seed fundraising of $30 million in September 2024, valuing the company at around $150 million.

In June 2025, Chai unveiled Chai‑2, its second-generation AI model capable of designing brand-new antibody molecules from scratch with a near 20% success rate. That’s a massive improvement over traditional lab methods, which succeed less than 0.1% of the time. Chai then raised $70 million in Series A financing led by Menlo Ventures (via its Anthology Fund), with participation from investors including Yosemite, DST Global Partners, SV Angel, Avenir, DCVC, and existing backers like Thrive, OpenAI, Dimension, Neo, Lachy Groom, and Fred Ehrsam. This round raised the company’s valuation to about $550 million.