ARCH Venture Funds Buy $50.0 Million of Lyell Immunopharma Stock

Two ARCH Venture entities bought a combined $50.00 million of Lyell Immunopharma, Inc. (Nasdaq: LYEL) stock, according to Form 4 filings with the Securities and Exchange Commission disclosed Thursday, Nov. 5, 2026.

ARCH Venture Fund XIII, L.P. bought 2,321,262 shares on Nov. 4 at $10.77 per share, a total of $25.00 million. After the purchase, it held 3,747,790 shares. The fund is a 10% owner of the company and is not an officer or director.

ARCH Venture Partners IX, LLC reported the same trade: 2,321,262 shares at $10.77, or $25.00 million, leaving it with 3,747,790 shares after the purchase. It is also a 10% owner. Neither purchase was made under a pre-arranged trading plan.

Stock move

Lyell's stock closed at $15.00 on Thursday, Nov. 5, after rising 70.6% over the prior 20 sessions. On Friday, Nov. 6, the stock fell 0.9% to close at $14.86, while the S&P 500 ETF gained 0.3%.

Company context

Lyell reported a third-quarter net loss of $45.5 million, compared with $38.8 million a year earlier, on revenue of $3 thousand. Separately, the company announced a private placement of shares at $10.77 per share, the same price paid in the ARCH purchases, according to an 8-K filing. At Sept. 30, Lyell held cash, equivalents and investments totaling $194.0 million.