Company · Ownership research

Upstream Bio, Inc. UPB

CIK 0002022626

Form 3 statements with an event date from Nov 1, 2023 to Nov 10, 2026.

Insider trading Initial holdings Institutional holders

Some filings are submitted jointly by several insiders. The SEC form does not apportion the reported figures between them, so results include every joint filer.

Where insider ownership starts.

Form 3 is an initial ownership statement filed when someone becomes a reporting insider. These holdings do not mean they bought shares that day.

202414 of 14 statements

Holdings date	Insider	Initial holdings
Dec 16, 2024	Ambrose Allison General Counsel	No securities reported	▾
Oct 10, 2024	Wellington Biomedical Innovation Master Investors (Cayman) II L.P. 10% owner	1 derivative holding	▾
Oct 10, 2024	Sutherland Everett Rand Chief Executive Officer · Director	2 derivative holdings	▾
Oct 10, 2024	Chimovits Erez Director · 10% owner	2 stock holdings · 4 derivative holdings	▾
Oct 10, 2024	Beckman Daniella Director	No securities reported	▾
Oct 10, 2024	Houghton Adam Chief Business Officer	5 derivative holdings	▾
Oct 10, 2024	Ruddy Marcella K. Director	3 derivative holdings	▾
Oct 10, 2024	Ratcliffe Liam Director	No securities reported	▾
Oct 10, 2024	Deykin Aaron Chief Medical Officer	5 derivative holdings	▾
Oct 10, 2024	Fleming Harold Edward Director	No securities reported	▾
Oct 10, 2024	ORBIMED ADVISORS LLC · OrbiMed Israel GP II, L.P. · OrbiMed Advisors Israel II Ltd · OrbiMed Capital GP VIII LLC Director · 10% owner / Director · 10% owner / Director · 10% owner / Director · 10% owner	2 stock holdings · 4 derivative holdings	▾
Oct 10, 2024	Renaud Ronald C JR Director	5 derivative holdings	▾
Oct 10, 2024	GRAY MICHAEL CFO and COO	2 derivative holdings	▾
Oct 10, 2024	Blavatnik Len · Access Industries Holdings LLC · ACCESS INDUSTRIES MANAGEMENT, LLC · AI Biotechnology LLC · AI Upstream LLC 10% owner / 10% owner / 10% owner / 10% owner / 10% owner	2 derivative holdings	▾

Showing 14 / 14 statements in 2024. The complete set is available through the API.

Upstream Bio, Inc. · UPB

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