Frazier Life Sciences Public Fund, L.P. - 01 Nov 2025 SCHEDULE 13D/A Report for PHATHOM PHARMACEUTICALS, INC. Common Stock, $0.0001 par value per share (PHAT)

Filing manager
Frazier Life Sciences Public Fund, L.P.
Reporting owner
James N. Topper
Security
PHATHOM PHARMACEUTICALS, INC. Common Stock, $0.0001 par value per share
Beneficially owned shares
5,985,327 shares
Ownership signal CIK-linked ownership evidence from parsed SEC filings. 2 signals
Large-stake signal

Form

SCHEDULE 13D/A

Active or control-oriented beneficial ownership filing.

Ownership

8.6%

Beneficial ownership of this reported class.

Shares

5,985,327 shares

Shares beneficially owned as disclosed.

Event date

01 Nov 2025

Date tied to the ownership event or amendment.

Accepted by SEC

04 Nov 2025

EDGAR acceptance date.

How to read this large-stake filing
  • Schedule 13D/G filings focus on beneficial ownership stakes, not a full portfolio.
  • Compare this filing with the holder history and issuer page before treating the percentage as a current position.
  • Use amendments to understand whether the disclosed stake increased, decreased, or changed reporting status.
Class ownership
8.6%
Subject security Names, identifiers, and filing context for this profile. 2 source fields
Symbol
PHAT
Shares outstanding
69,596,826 shares
Source evidence Original filing metadata and source links for verification. 5 source fields
SEC form
SCHEDULE 13D/A
Accepted by SEC
04 Nov 2025, 17:24:56 UTC
Event date
01 Nov 2025
Prior SEC filing
20 Aug 2025
Source filing
View source filing

Key filing fact

Frazier Life Sciences Public Fund, L.P. disclosed 8.6% ownership in PHATHOM PHARMACEUTICALS, INC. Common Stock, $0.0001 par value per share (PHAT) on 01 Nov 2025.

Key facts

  • Frazier Life Sciences Public Fund, L.P. filed SCHEDULE 13D/A for PHATHOM PHARMACEUTICALS, INC. Common Stock, $0.0001 par value per share (PHAT).
  • Disclosed ownership: 8.6%.
  • Date of event: 01 Nov 2025.

Change

  • Previous schedule filing date: 20 Aug 2025.
  • Current filing was accepted on 04 Nov 2025, 17:24.

Research use

  • This page turns one Schedule 13D/G filing into a quick large-stake read before the raw reporting-person rows.
  • Use the linked SEC filing as the source of truth for ownership percentages, shares, and reporting-party details.

Evidence

Backed by Schedule 13D/13G

Beneficial ownership values are sourced from the original SEC Schedule 13D/13G filing.

View source filing

Reporting persons

Disclosed reporting parties (17)

Names, ownership percentages, voting power, signatures, titles, and CIKs as disclosed in this Schedule 13D/G filing.

Name Ownership Shares owned Sole voting power Shared voting power Signature Title CIK
Frazier Life Sciences Public Fund, L.P. 7.5% 5,323,356 0 5,323,356 /s/ Steve R. Bailey By Steve R. Bailey, CFO of FHMLSP, L.L.C., GP of FHMLSP, L.P., GP of Frazier Life Sciences Public Fund, L.P. 0001863769
FHMLSP, L.P. 7.5% 5,323,356 0 5,323,356 /s/ Steve R. Bailey By Steve R. Bailey, CFO of FHMLSP, L.L.C., GP of FHMLSP, L.P. 0001879466
FHMLSP, L.L.C. 7.5% 5,323,356 0 5,323,356 /s/ Steve R. Bailey By Steve R. Bailey, CFO of FHMLSP, L.L.C. 0001879465
Frazier Life Sciences X, L.P. 0.1% 59,403 0 59,403 /s/ Steve R. Bailey By Steve R. Bailey, CFO of FHMLS X, L.L.C., GP of FHMLS X, L.P., GP of Frazier Life Sciences X, L.P. 0001790879
FHMLS X, L.P. 0.1% 59,403 0 59,403 /s/ Steve R. Bailey By Steve R. Bailey, CFO of FHMLS X, L.L.C., GP of FHMLS X, L.P. 0001790880
FHMLS X, L.L.C. 0.1% 59,403 0 59,403 /s/ Steve R. Bailey By Steve R. Bailey, CFO of FHMLS X, L.L.C. 0001790811
Frazier Life Sciences XI, L.P. 1.4% 980,286 0 980,286 /s/ Steve R. Bailey By Steve R. Bailey, CFO of FHMLS XI, L.L.C., GP of FHMLS XI, L.P., GP of Frazier Life Sciences XI, L.P. 0001911592
FHMLS XI, L.P. 1.4% 980,286 0 980,286 /s/ Steve R. Bailey By Steve R. Bailey, CFO of FHMLS XI, L.L.C., GP of FHMLS XI, L.P. 0001911580
FHMLS XI, L.L.C. 1.4% 980,286 0 980,286 /s/ Steve R. Bailey By Steve R. Bailey, CFO of FHMLS XI, L.L.C. 0001911623
Frazier Life Sciences IX, L.P. 8.2% 5,827,415 0 5,827,415 /s/ Steve R. Bailey By Steve R. Bailey, CFO of FHMLS IX, L.L.C., GP of FHMLS IX, L.P., GP of Frazier Life Sciences IX, L.P. 0001720320
FHMLS IX, L.P. 8.2% 5,827,415 0 5,827,415 /s/ Steve R. Bailey By Steve R. Bailey, CFO of FHMLS IX, L.L.C., GP of FHMLS IX, L.P. 0001782789
FHMLS IX, L.L.C. 8.2% 5,827,416 0 5,827,416 /s/ Steve R. Bailey By Steve R. Bailey, CFO of FHMLS IX, L.L.C. 0001782791
Frazier Life Sciences XII, L.P. 0.4% 276,029 0 276,029 /s/ Gordon Empey By Gordon Empey, General Counsel of FHMLS XII, L.L.C., GP of FHMLS XII, L.P., GP of Frazier Life Sciences XII, L.P. 0002052255
FHMLS XII, L.P. 0.4% 276,029 0 276,029 /s/ Gordon Empey By Gordon Empey, General Counsel of FHMLS XII, L.L.C., GP of FHMLS XII, L.P. 0002052246
FHMLS XII, L.L.C. 0.4% 276,029 0 276,029 /s/ Gordon Empey By Gordon Empey, General Counsel of FHMLS XII, L.L.C. 0002052177
James N. Topper 8.6% 5,985,327 98,508 5,886,819 /s/ Steve R. Bailey By Steve R. Bailey, Attorney-in-Fact for James N. Topper, pursuant to a Power of Attorney, a copy of which was filed with the SEC on July 31, 2017 0001341382
Patrick J. Heron 8.4% 5,901,756 14,937 5,886,819 /s/ Steve R. Bailey By Steve R. Bailey, Attorney-in-Fact for Patrick J. Heron, pursuant to a Power of Attorney, a copy of which was filed with the SEC on July 31, 2017 0001365617
We use cookies and similar technologies to provide certain features, enhance the user experience and, if you allow them, measure engagement and deliver advertising. Analytics and marketing storage stay off until you grant consent. By clicking on "Agree and continue", you declare your consent to the use of the selected optional cookies. Manage preferences to update or revoke optional consent for future visits. For more information, see our Privacy Policy .