L3VLUP
ProSign in

MRK in the 13F filings

Merck & Co Inc · CUSIP 58933Y105

Sector · Pharmaceuticals and biotechnologyTheme · Healthcare: biopharma and medtech· L3VLUP-definedTheme · Pharmaceutical preparations
Quarter
Q3 2026 · early filersQ2 2026Q1 2026Q4 2025Q3 2025Q2 2025Q1 2025Q4 2024Q3 2024Q2 2024Q1 2024Q4 2023
Quarter end
31 Dec 2025
the date the book describes
Filed
27 Oct 2026
latest of these filings; the earliest 22 Jan 2026
Managers listing it
39
at least, of 95 tracked, among listed positions
Comparable managers
92
filed both Q3 2025 and Q4 2025; 31 listed it in both
Shares listed
256,447,189
combined, among listed positions
Reported value
$27.0bn
combined, at the quarter end

Among the 92 comparable managers: 25 buyers (opened or added shares) and 19 sellers (trimmed or exited), at least, among listed positions. Their net change in shares was +25,773,076.

Managers listing MRK in Q4 2025

Share of 13F value is the position’s reported value over everything the manager reported that quarter. The share change is against Q3 2025, and only where both filings list the position. A rise in value with no rise in shares is the price, not buying.

39 of 39 holders

ActionFiling
Wellington Management Group LLP86,435,458$9.1bn1.59%Added+11,156,35417 Feb 2026 (the filing on sec.gov)
Fidelity (FMR LLC)40,836,566$4.3bn0.22%Added+7,409,81617 Feb 2026 (the filing on sec.gov)
Invesco Ltd20,546,185$2.2bn0.20%Added+701,24919 Feb 2026 (the filing on sec.gov)
T. Rowe Price Associates Inc18,753,390$2.0bn0.21%Added+5,152,06917 Feb 2026 (the filing on sec.gov)
Harris Associates LP14,088,705$1.5bn1.87%Added+4,265,09717 Feb 2026 (the filing on sec.gov)
AQR Capital Management LLC11,249,363$1.2bn0.62%Added+591,26417 Feb 2026 (the filing on sec.gov)
Arrowstreet Capital LP9,944,123$1.0bn0.61%Trimmed-8,764,58013 Feb 2026 (the filing on sec.gov)
AllianceBernstein LP8,632,385$909m0.29%Added+402,59217 Feb 2026 (the filing on sec.gov)
Citadel Advisors LLC6,821,331$718m0.11%Added+5,853,27717 Feb 2026 (the filing on sec.gov)
Millennium Management LLC6,800,351$716m0.30%Added+6,036,98317 Feb 2026 (the filing on sec.gov)
MFS Investment Management4,416,021$465m0.15%Trimmed-3,132,99922 Jan 2026 (the filing on sec.gov)
Marshall Wace LLP3,969,469$418m0.38%Added+3,085,56913 Feb 2026 (the filing on sec.gov)
D. E. Shaw & Co.3,518,464$370m0.20%Added+50,61217 Feb 2026 (the filing on sec.gov)
Neuberger Berman Group LLC3,039,898$320m0.24%Added+427,88527 Oct 2026 (the filing on sec.gov)
Balyasny Asset Management LLC2,187,260$230m0.29%Added+1,502,30317 Feb 2026 (the filing on sec.gov)
Capital Research Global Investors2,112,142$222munder 0.1%Trimmed-198,47311 Feb 2026 (the filing on sec.gov)
Janus Henderson Group Ltd1,885,140$198m0.09%Trimmed-230,40117 Feb 2026 (the filing on sec.gov)
Man Group PLC1,843,528$194m0.33%Trimmed-727,38317 Feb 2026 (the filing on sec.gov)
Acadian Asset Management LLC1,594,669$168m0.28%Trimmed-608,29610 Feb 2026 (the filing on sec.gov)
Susquehanna International Group LLP1,459,133$154munder 0.1%Added+160,33417 Feb 2026 (the filing on sec.gov)
Artisan Partners LP1,383,297$146m0.22%Added+48,70017 Feb 2026 (the filing on sec.gov)
Point72 Asset Management LP1,338,449$141m0.16%Added+75,69617 Feb 2026 (the filing on sec.gov)
Woodline Partners LP1,004,699$106m0.41%Added+96,15517 Feb 2026 (the filing on sec.gov)
Holocene Advisors LP885,760$93m0.20%Added+239,74917 Feb 2026 (the filing on sec.gov)
Bridgewater Associates LP310,221$33m0.12%Trimmed-203,72213 Feb 2026 (the filing on sec.gov)
Page 1 of 2

Largest increases and reductions, by shares

Q3 2025 to Q4 2025, among managers that listed it in both quarters or opened it.

Increases

Reductions

New positions and exits

At least these many: a manager is shown exiting only where its own filing shows the position gone.

New (2)

Exited (5)

Ownership over time

Every quarter on file. A quarter-end value moves with the price as well as with the shares held; buyers and sellers count comparable managers, by shares.
38 in Q3 2024 to 25 in Q2 2026

Tracked managers listing it, at least.

02040602014201620182020202220242026
the quarter shown share split complete books; unmarked quarters rest on listed positionsClick a quarter to open it.
MRK by quarter
QuarterHoldersReported valueBuyersSellers
Q2 201323$25.9bnn.a.n.a.
Q3 201324$25.4bnn.a.n.a.
Q4 201323$27.1bnn.a.n.a.
Q1 201424$31.2bnn.a.n.a.
Q2 201428$30.6bnn.a.n.a.
Q3 201432$30.5bnn.a.n.a.
Q4 201430$28.6bnn.a.n.a.
Q1 201529$28.8bnn.a.n.a.
Q2 201529$27.1bnn.a.n.a.
Q3 201525$23.0bnn.a.n.a.
Q4 201528$23.9bnn.a.n.a.
Q1 201628$23.8bnn.a.n.a.
Q2 201627$25.9bnn.a.n.a.
Q3 201627$27.5bnn.a.n.a.
Q4 201626$24.4bnn.a.n.a.
Q1 201731$24.7bnn.a.n.a.
Q2 201734$24.0bnn.a.n.a.
Q3 201731$23.7bnn.a.n.a.
Q4 201732$20.0bnn.a.n.a.
Q1 201830$17.5bnn.a.n.a.
Q2 201827$19.3bnn.a.n.a.
Q3 201827$22.9bnn.a.n.a.
Q4 201826$24.4bnn.a.n.a.
Q1 201926$24.4bnn.a.n.a.
Q2 201928$23.3bnn.a.n.a.
Q3 201931$23.2bnn.a.n.a.
Q4 201934$24.0bnn.a.n.a.
Q1 202033$18.5bnn.a.n.a.
Q2 202034$18.6bnn.a.n.a.
Q3 202035$20.2bnn.a.n.a.
Q4 202034$19.1bnn.a.n.a.
Q1 202133$16.6bnn.a.n.a.
Q2 202131$15.1bnn.a.n.a.
Q3 202131$15.2bnn.a.n.a.
Q4 202126$15.0bnn.a.n.a.
Q1 202234$17.4bnn.a.n.a.
Q2 202234$19.0bnn.a.n.a.
Q3 202235$17.2bnn.a.n.a.
Q4 202235$25.2bnn.a.n.a.
Q1 202333$26.6bnn.a.n.a.
Q2 202334$30.1bnn.a.n.a.
Q3 202339$26.7bnn.a.n.a.
Q4 202341$29.3bn2220
Q1 202437$37.1bn2119
Q2 202438$33.0bn2118
Q3 202438$29.1bn2317
Q4 202435$23.7bn1819
Q1 202536$20.8bn2018
Q2 202531$18.5bn1813
Q3 202536$19.0bn1818
Q4 202532$26.8bn2519
Q1 202630$28.9bn1327
Q2 202625$29.2bn1424

Compare with…

Holders over time, buyers and sellers, and the managers holding both, side by side for up to four stocks.

MRK and LLY →MRK and JNJ →MRK and VRTX →Choose a stock to compare with MRK →

How much of the picture this is

A 13F is a manager’s long US-listed equity book at a quarter end, filed up to 45 days later. It shows no shorts, cash, bonds or performance, and it is never today’s portfolio. Large books are listed to their largest positions, so a manager missing from this table may still hold a small position below that line. These are 95 tracked managers, not the institutional market.

Which funds own MRK, latest filings →Back to the 13F Explorer →