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Merck & Co., Inc.

Health CareS&P 500

Merck & Co., Inc. insider trading

Merck & Co., Inc. files with the SEC as a Pharmaceutical Preparations company headquartered in Rahway, NJ. Every time one of its executives or directors buys or sells the stock, the filing appears here the moment it reaches the SEC — with grants and option exercises set apart from the trades that cost the insider their own money.

From SEC filings

Recent MRK insider transactions

5 insiders traded MRK on the open market between Aug 05, 2026 and Aug 13, 2026 — 17 sales worth $30M.

Bought
—
Sold
$30M

none on a 10b5-1 plan

Net
−$30M
Insiders
5

Open-market purchases (code P) and sales (code S) from Merck & Co., Inc.'s own SEC Form 4 filings. Grants and option exercises are excluded — they are compensation, not decisions. Share counts are derived from the reported value and price. Verify any figure against the original filing before acting on it; this is monitoring, not advice.

Filing history last read from EDGAR on Sep 21, 2026. The live dashboard shows new filings the moment they clear.

Every MRK Form 4 on SEC.gov

SEC Form 4 data, Q3 2024 to Q2 2026

MRK insider trading by quarter

Between Jul 01, 2024 and Jun 30, 2026, 12 insiders traded MRK on the open market: 2 purchases worth $1.6M and 22 sales worth $43.8M. In the last four quarters alone: 0 purchases and 18 sales ($42M), by 10 insiders.

QuarterBoughtSold
Q2 2026——
Q1 2026—−$40.7M16 sales
Q4 2025—−$1.3M2 sales
Q3 2025——
Q2 2025—−$352.7K1 sale
Q1 2025+$1.6M2 buys−$1.4M3 sales
Q4 2024——
Q3 2024——
Largest purchase
+$1.3M of MRK by Baker Douglas M Jr (Director) on Feb 05, 2025.
Largest sale
−$6.8M of MRK by Zachary Jennifer (EVP, General Counsel) on Feb 09, 2026.

Open-market transactions through Jun 30, 2026most recent first

  • Guindo Chirfi

    Chief Marketing Officer

    −$1.2M

    Feb 12, 2026

    10,000 sh · $121.46

  • Li Dean Y

    Executive VP & President, MRL

    −$1.2M

    Feb 10, 2026

    10,235 sh · $117.52

  • Zachary Jennifer

    EVP, General Counsel

    −$6.8M

    Feb 09, 2026

    56,792 sh · $119.15

  • Zachary Jennifer

    EVP, General Counsel

    −$4.6M

    Feb 09, 2026

    38,835 sh · $119.15

  • Zachary Jennifer

    EVP, General Counsel

    −$3.1M

    Feb 09, 2026

    25,946 sh · $119.15

  • Guindo Chirfi

    Chief Marketing Officer

    −$1.2M

    Feb 09, 2026

    10,000 sh · $118.41

  • DeLuca Richard R.

    EVP&Pres, Merck Animal Heallth

    −$4.6M

    Feb 06, 2026

    37,685 sh · $120.92

  • Oosthuizen Johannes Jacobus

    President, U.S. Market

    −$1.8M

    Feb 06, 2026

    15,000 sh · $121.87

  • Williams David Michael

    EVP,Chief Info&Digital Officer

    −$609.6K

    Feb 06, 2026

    5,000 sh · $121.91

  • Guindo Chirfi

    Chief Marketing Officer

    −$2.4M

    Feb 05, 2026

    20,000 sh · $121.88

  • Litchfield Caroline

    EVP & CFO

    −$5M

    Feb 04, 2026

    41,997 sh · $119.61

  • Davis Robert M

    Chairman, CEO & President · Director

    −$3.8M

    Feb 04, 2026

    32,462 sh · $118.35

  • Li Dean Y

    Executive VP & President, MRL

    −$1.8M

    Feb 04, 2026

    15,087 sh · $118.77

  • Davis Robert M

    Chairman, CEO & President · Director

    −$1.8M

    Feb 04, 2026

    14,972 sh · $117.38

  • Smart Dalton E. III

    SVP Fin. - Global Controller

    −$478.7K

    Feb 04, 2026

    4,000 sh · $119.68

From SEC's quarterly Form 3, 4 and 5 data sets: code P purchases and code S sales of common stock, by the date the trade happened. Where a fund and the people who control it each report the same block, it is counted once. Trades made in the last days of Q2 2026 but filed after it closed arrive with SEC's next quarterly release.

Merck & Co., Inc. company record

SEC industry classification
Pharmaceutical Preparations
Headquarters
Rahway, NJ
Incorporated in
NJ
Listed on
NYSE
SEC Central Index Key
0000310158
Previously filed as
SCHERING PLOUGH CORP

Sourced from this company's own SEC submissions record. The industry label is SEC's Standard Industrial Classification, which is more specific than the Health Care sector shown above.

After insiders bought MRK

What the stock actually did in the 90 days following each open-market purchase

Don't check MRK — let it ping you

Get told the moment an insider moves on MRK

Pro watches Merck & Co., Inc. for you and sends a Telegram ping within moments of a Form 4 clearing EDGAR — a C-suite open-market buy, a cluster, a 10b5-1 regime break — long before it reaches the press. Add MRK to a watchlist, see each mover's benchmark-measured track record and which legendary funds hold it, and read the full filing history instead of the last 72 hours.

Track MRK on the live dashboardFilings on SEC.gov

The live dashboard is free to open. Alerts, watchlists, full filing history and each mover's benchmark-measured track record are Pro. Monitoring, not advice.

How to read MRK insider activity

Open-market purchase (code P)
An insider spending their own money at market price. This is the only buy code that reliably carries signal — it is a decision, not compensation.
Grants and option exercises (codes A, M)
Scheduled compensation. Most "insider buying" headlines are really this, which is why InsiderPulse weights it at a fraction of a real purchase.
Cluster buy
Two or more different insiders buying on the open market in the same window. One executive buying can mean anything; three is much harder to explain away.

Other Health Care tickers

TMOABTDHRPFEAMGNBMYGILDVRTXREGNISRGSYKBSX
This week on the tape: who actually chose to sellThe weekly split of scheduled 10b5-1 selling vs deliberate sales, with the deciders named.

Questions

Are MRK insiders buying or selling?
Between Aug 05, 2026 and Aug 13, 2026, 5 Merck & Co., Inc. insiders made no open-market purchases and 17 sales worth $30M, a net sale of $30M.
How much MRK stock have insiders bought and sold in the last two years?
Between Jul 01, 2024 and Jun 30, 2026, 12 Merck & Co., Inc. insiders made 2 open-market purchases worth $1.6M and 22 sales worth $43.8M. In the four quarters to Jun 30, 2026: no purchases and 18 sales ($42M). The largest purchase was Baker Douglas M Jr buying $1.3M on Feb 05, 2025. The largest sale was Zachary Jennifer selling $6.8M on Feb 09, 2026.
What was the largest recent MRK insider trade?
Zachary Jennifer (EVP, General Counsel) sold $10.7M of MRK stock on Aug 12, 2026 at about $133.46 a share.
When did an insider last buy MRK shares?
No open-market purchase by a Merck & Co., Inc. insider appears in the filings from Aug 05, 2026 to Aug 13, 2026 — every recorded open-market transaction in that period was a sale. Before that, the most recent purchase in SEC's data was Thulin Inge G buying $250K on Feb 06, 2025.
Where does MRK insider trading data come from?
From the Form 4 filings Merck & Co., Inc.'s officers, directors and 10% owners must send the SEC within two business days of a trade. Each row on this page links to its original filing on SEC EDGAR. Share grants and option exercises are kept apart from open-market purchases and sales, because only the latter cost the insider their own money.

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