0001782303 2026-06-15 2026-06-15 0001782303 dei:FormerAddressMember 2026-06-15 2026-06-15 0001782303 false 8-K 2026-06-15 Boundless Bio, Inc. DE 001-41989 83-0751369 11099 North Torrey Pines Road, Suite 150 La Jolla CA 92037 (858) 766-9912 10955 Alexandria Way, Suite 100 San CA 92121 false false false false Common Stock, par value $0.0001 per share BOLD NASDAQ true false