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Company profile

Merck & Co., Inc. Insider Trading

MRK

Every SEC Form 4 insider trading filing for Merck & Co., Inc. (MRK) since April 2023: open-market buys and sells by directors and officers, option exercises, and cluster activity, updated as each filing is reported to the SEC. Why 2023?

Exchange
NYSE
Sector
Pharmaceutical Preparations
CIK
0000310158
Filings
269
Insiders
32
Last filing
2026-08-13
SEC EDGAR ↗Yahoo Finance ↗Finviz ↗Stock Analysis ↗

Activity summary

No insider transactions in the last 30 days. The most recent was on August 13, 2026, when Chirfi Guindo sold 10,000 shares. 269 filings from 32 insiders are on record below.

Three year balance

Buy and sell value by quarter, Q4 23 to Q3 26. Merck & Co., Inc. insiders are net buyers across the period shown.

PurchasesSales
Q4 23$54.3MQ1 24Q2 24Q3 24Q4 24Q1 25Q2 25Q3 25Q4 25Q1 26Q2 26Q3 26

Bars below the rule are sales, above are purchases. Largest quarter on the chart is $54.3M.

90 day insight

Over the last 90 days, Merck & Co., Inc. insiders bought $11.6M (19 transactions) and sold $30.0M (17 transactions).

  • Most active insider: David Michael Williams with 9 transactions totaling $10.7M.
  • Largest single sale: $10.7M by Jennifer Zachary on Aug 12, 2026.

Activity is mixed: buys and sales are roughly balanced.

Insider Transactions

Sourced from SEC EDGAR Form 4 filings. Updated hourly.

DateInsiderCompanyTypeSharesPriceValueReturn
Aug 13, 2026Chirfi GuindoMRK
Sale
10,000$135.00$1.35M+7.1% 1m
Aug 12, 2026Richard R. DeLucaMRK
Sale
11,099$131.61$1.46M+7.8% 1m
Aug 12, 2026Richard R. DeLucaMRK
Sale
600$132.04$79K+7.8% 1m
Aug 12, 2026Jennifer ZacharyMRK
Option Exercise
41,494$117.89$4.89M+7.1% 1m
Aug 12, 2026Jennifer ZacharyMRK
Option Exercise
13,433$84.71$1.14M+7.1% 1m

45 more transactions hidden

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Top insiders

By total value filed.

Jennifer ZacharyEVP, General Counsel3 filings−$4.7M
David Michael WilliamsEVP,Chief Info&Digital Officer6 filings−$2.9M
Richard R. DeLucaEVP&Pres, Merck Animal Heallth8 filings−$6.7M
David R. MaraldoEVP & Pres. MMD6 filings−$869K
Chirfi GuindoEVP, Access, Policy & Comms2 filings−$3.3M

Institutional Ownership

Top 13F-HR holders of Merck & Co., Inc. as of 2026-06-30

↓ decreasing
Total reported AUM
$83.42B
QoQ change
-60.3%
Reporting period
2026-06-30
#1
State Street Corp
CIK 0000093751
$15.57B
120.4M shares
#2
BlackRock, Inc.
CIK 0002012383
$10.91B
84.9M shares
#3
BlackRock, Inc.
CIK 0002012383
$6.67B
51.9M shares

Data source: quarterly 13F-HR filings: institutional holders report positions within 45 days of quarter end. Joined with insider activity above: see who's loading up institutionally while insiders are trading. Full 13F-HR API →

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Form4API, StockholmNot affiliated with the SEC or EDGAR. Data sourced from public EDGAR filings. Not investment advice.

Congressional Trading

Disclosed MRK trades under the STOCK Act

Total trades
42
Purchases
20
Sales
22
Gilbert Ray Cisneros, Jr.
Democrat · House · CA
5 buys
3 sells
Julie Johnson
Democrat · House · TX
2 buys
3 sells
Marjorie Taylor Greene
Unknown · House · GA
3 buys
0 sells
Jared Moskowitz
Democrat · House · FL
0 buys
3 sells
Robert P. Bresnahan, Jr.
Republican · House · PA
1 buy
2 sells
See all 16 members who traded MRK →

Sourced from U.S. House Clerk periodic transaction reports (House coverage only). Trade counts reflect disclosed filings only. The STOCK Act allows up to 45 days between a trade and its disclosure, so this reflects recent disclosures, not real-time trading. Full congressional trading API →

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