Form 3 - Initial statement of beneficial ownership of securities:
SEC Accession No. 0000950170-24-114155
Filing Date
2024-10-10
Accepted
2024-10-10 20:14:30
Documents
2
Period of Report
2024-10-10

Document Format Files

Seq Description Document Type Size
1 3 ownership.html 3  
1 3 ownership.xml 3 5340
2 EX-24 ck0002022626-ex24.htm EX-24 13995
  Complete submission text file 0000950170-24-114155.txt   20772
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)

Mailing Address C/O TECTONIC THERAPEUTIC, INC. 490 ARSENAL WAY, SUITE 210 WATERTOWN MA 02472
Business Address
Ruddy Marcella K. (Reporting) CIK: 0002023849 (see all company filings)

Type: 3 | Act: 34 | File No.: 001-42366 | Film No.: 241366131