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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

Q3 2026: 5 of 95 managers have filed so far; the filing deadline is 16 November 2026. Its figures cover those filers only, so it is not yet a picture of the tracked managers.

Quarter end
30 Sep 2026
the date the book describes
Filed
9 Nov 2026
latest of these filings; the earliest 9 Nov 2026
Managers listing it
2
at least, of 95 tracked, among listed positions
Comparable managers
5
filed both Q2 2026 and Q3 2026; 2 listed it in both
Shares listed
3,944,937
combined, among listed positions
Reported value
$573m
combined, at the quarter end

Among the 5 comparable managers: 0 buyers (opened or added shares) and 2 sellers (trimmed or exited), at least, among listed positions. Their net change in shares was -660,068.

Managers listing MRK in Q3 2026

Share of 13F value is the position’s reported value over everything the manager reported that quarter. The share change is against Q2 2026, and only where both filings list the position. A rise in value with no rise in shares is the price, not buying.

2 of 2 holders

ActionFiling
Acadian Asset Management LLC3,062,568$445m0.52%Trimmed-632,7619 Nov 2026 (the filing on sec.gov)
Squarepoint Ops LLC882,369$128m0.14%Trimmed-27,3079 Nov 2026 (the filing on sec.gov)

Largest increases and reductions, by shares

Q2 2026 to Q3 2026, among managers that listed it in both quarters or opened it.

Increases

No increase among listed positions.

Reductions

New positions and exits

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

New (0)

No new position among listed positions.

Exited (0)

No exit shown by a manager’s own filing.

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.
35 in Q4 2024 to 2 in Q3 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
Q3 20262$573m02

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 →