Form 3 - Initial statement of beneficial ownership of securities:
SEC Accession No. 0000950170-24-114166
Filing Date
2024-10-10
Accepted
2024-10-10 20:48:22
Documents
1
Period of Report
2024-10-10

Document Format Files

Seq Description Document Type Size
1 3 ownership.html 3  
1 3 ownership.xml 3 3179
  Complete submission text file 0000950170-24-114166.txt   4774
Mailing Address 280 CONGRESS STREET BOSTON MA 02210
Business Address 280 CONGRESS STREET BOSTON MA 02210 617-951-5000
Wellington Biomedical Innovation Master Investors (Cayman) II L.P. (Reporting) CIK: 0001903360 (see all company filings)

State of Incorp.: E9
Type: 3 | Act: 34 | File No.: 001-42366 | Film No.: 241366160

Mailing Address 890 WINTER STREET, SUITE 200 WALTHAM MA 02451
Business Address 890 WINTER STREET, SUITE 200 WALTHAM MA 02451 781-208-2466
Upstream Bio, Inc. (Issuer) CIK: 0002022626 (see all company filings)

EIN.: 000000000 | State of Incorp.: DE | Fiscal Year End: 1231
SIC: 2834 Pharmaceutical Preparations
(CF Office: 03 Life Sciences)