Merck & Co., Inc. — 13F Holdings & Portfolio

CIK 310158 · latest 13F-HR filed 2026-08-07

Merck & Co., Inc. manages $526.4M in 13F-reported U.S. long-equity assets across 13 reported positions as of its 2026-06-30 13F-HR filing. Its largest disclosed positions are PSNL (35.75%), MRNA (30.71%), KYMR (16.82%). Quarter over quarter (versus its 2026-03-31 filing) the fund opened 3 new positions, exited 4, added to 8, and trimmed 2.

AUM is the long-equity portion reported on Form 13F-HR. Excludes short positions, cash, foreign holdings, and non-13F assets. For informational purposes only — not investment advice.

Filer Information
Address
126 EAST LINCOLN AVENUE
P.O. BOX 2000
RAHWAY, NJ 07065
Phone
(908) 740-4000
Filing Manager
Merck & Co., Inc.
RAHWAY, NJ
Signatory
Kelly Grez
Corporate Secretary
Loading holdings…
AUM

$526.4M

Long-equity book

Holdings

13

Distinct positions

Period

2026-06-30

Filed 2026-08-07

Q/Q Activity

+3 / −4 / ↑8 / ↓2

vs 2026-03-31

Firm Profile & Key People
Name Title / Status Ownership Type

Top Adds (vs prior quarter)

  • PERSONALIS INC$98.7M +110.4%
  • MODERNA INC$44.4M +37.9%
  • KYMERA THERAPEUTICS INC$24.2M +37.7%
  • AKTIS ONCOLOGY INC$13.7M +80.2%
  • EIKON THERAPEUTICS INC$4.1M +23.3%
Show all 8

Top Trims

  • ALECTOR INC-$496.4K -6.5%
  • VIRIDIAN THERAPEUTICS INC-$111.2K -6.1%
Show all 2

New Positions

  • ENTRADA THERAPEUTICS INC$12.8M
  • SUTRO BIOPHARMA INC$9.0M
  • EVAXION BIOTECH A/S$3.8M
Show all 3

Exited Positions

  • ENTRADA THERAPEUTICS INC$22.0M
  • SUTRO BIOPHARMA INC$6.8M
  • EVAXION BIOTECH A/S$4.5M
  • CARISMA THERAPEUTICS INC$47.9K
Show all 4
All Holdings

Rows tagged Call or Put are options positions, not stock. Per SEC Form 13F-HR, Value shows the notional value of the underlying (shares covered × underlying price), not the option premium. Shares is the number of underlying shares covered (divide by 100 for contract count).

# Issuer Symbol CUSIP Value Weight Shares Type
1 PERSONALIS INC PSNL 71535D106 $188.2M 35.75% 14,044,943 SH
2 MODERNA INC MRNA 60770K107 $161.6M 30.71% 2,308,190 SH
3 KYMERA THERAPEUTICS INC KYMR 501575104 $88.5M 16.82% 772,165 SH
4 AKTIS ONCOLOGY INC AKTS 01021M104 $30.7M 5.83% 952,844 SH
5 EIKON THERAPEUTICS INC EIKN 282564103 $21.7M 4.13% 1,666,666 SH
6 ENTRADA THERAPEUTICS INC TRDA 29384C108 $12.8M 2.43% 1,739,768 SH
7 SUTRO BIOPHARMA INC STRO 869367201 $9.0M 1.72% 272,351 SH
8 ALECTOR INC ALEC 014442107 $7.1M 1.35% 3,545,719 SH
9 EVAXION BIOTECH A/S EVAX 29970R303 $3.8M 0.71% 1,214,126 SH
10 VIRIDIAN THERAPEUTICS INC VRDN 92790C104 $1.7M 0.33% 93,414 SH
11 XILIO THERAPEUTICS INC XLO 98422T209 $1.0M 0.19% 105,982 SH
12 TUHURA BIOSCIENCES INC HURA 898920103 $45.5K 0.01% 19,445 SH
13 NEUPHORIA THERAPEUTICS INC NEUP 64136E102 $43.8K 0.01% 10,027 SH
Filing History
Period Filed AUM Holdings Accession
2026-06-30 2026-08-07 $526.4M 13 0000310158-26-000210
2026-03-31 2026-05-13 $349.4M 14 0000310158-26-000141
2025-12-31 2026-02-17 $276.3M 12 0000310158-26-000055
2025-09-30 2025-11-12 $228.0M 13 0000310158-25-000063