Summit Therapeutics Inc. 4

Co-CEO Robert W. Duggan purchased 100,000 shares of Summit Therapeutics Inc. (SMMT) common stock on the open market at $14.60 per share on June 4, 2026.

On June 4, 2026, Summit Therapeutics Inc. Co-Chief Executive Officer Robert W. Duggan reported an open-market purchase of 100,000 shares of Summit Therapeutics common stock at a price of $14.60 per share, for an aggregate cost of approximately $1.46 million. Following this transaction, he reported indirect beneficial ownership of 25,824,474 shares through the Mahkam Zanganeh Revocable Trust (with his spouse as trustee), alongside additional indirect positions consisting of 10,199,776 shares held by the Shaun Zanganeh Irrevocable Trust, 76,680 shares held by an immediate family member of his spouse, and 31,000 shares held directly by his spouse, while also disclosing a very large separate direct holding of 570,073,879 shares of common stock. The filing notes that Mr. Duggan disclaims beneficial ownership of some of these indirect holdings except to the extent of his pecuniary interest, but the net effect is a sizable incremental insider share purchase layered on top of already very substantial existing ownership.

Filing Facts

CIK

1599298

Ticker

SMMT

Form

4

Source Type

sec

Accession

0001055919-26-000005

Alert Tier

8