Historical shareholding details of Wellington Management Company LLP holdings in Upstream Bio Inc. (UPB)

Monthly changes of Wellington Management Company LLP shareholding in Upstream Bio Inc. over the previous months

Month	Name	Total no. shares held	Percent Holding
Month	Name	Total no. shares held	Percent Holding
Mar 31, 2025	Wellington Management Company Llp	308,310	0.57%

Feb 28, 2025	Wellington Management Company Llp	308,310	0.58%

Jan 31, 2025	Wellington Management Company Llp	302,700	0.56%

Dec 31, 2024	Wellington Management Company Llp	1,583,154	2.95%
Dec 31, 2024	Wellington Management Company Llp	302,700	0.56%

Nov 30, 2024	Wellington Management Company Llp	302,700	0.56%