# MERCK & CO INC (MRK) — Institutional Ownership

Source: SEC EDGAR 13F filings, congressional STOCK Act disclosures, SEC Form 4 insider transactions.
CUSIP: 58933Y105
Page URL: https://superinvestorclub.com/stock/MRK
Last updated: 2026-08-29T13:48:53.565Z

## Summary

As of the most recent 13F filing period, MERCK & CO INC (MRK) is held by 14 tracked superinvestors with an aggregate position value of $1.78B representing 01207310995493221818217290013575012580551519446333025488548359251116711642 shares.

## Top institutional holders (14)

| Rank | Manager | Fund | Shares | Value | % of Portfolio | Period |
|------|---------|------|--------|-------|----------------|--------|
| 1 | [Bill Nygren](https://superinvestorclub.com/manager/73) | Harris Associates | 12073109 | $1.55B | 2.06% | 2026-06-30 |
| 2 | [Sarah Ketterer](https://superinvestorclub.com/manager/293) | Causeway Capital Management | 954932 | $122.7M | 1.33% | 2026-06-30 |
| 3 | [Kahn Brothers](https://superinvestorclub.com/manager/83) | Kahn Brothers Group | 218182 | $28.0M | 4.43% | 2026-06-30 |
| 4 | [Prem Watsa](https://superinvestorclub.com/manager/71) | Fairfax Financial Holdings | 172900 | $22.2M | 0.84% | 2026-06-30 |
| 5 | [Dodge & Cox](https://superinvestorclub.com/manager/16) | Dodge & Cox | 135750 | $17.4M | 0.01% | 2026-06-30 |
| 6 | [FPA Queens Road](https://superinvestorclub.com/manager/97) | Bragg Financial Advisors | 125805 | $16.2M | 0.43% | 2026-06-30 |
| 7 | [Mairs & Power](https://superinvestorclub.com/manager/92) | Mairs & Power | 51519 | $6.6M | 0.06% | 2026-06-30 |
| 8 | [Christopher Bloomstran](https://superinvestorclub.com/manager/32) | Semper Augustus Investments | 44633 | $5.7M | 0.65% | 2026-06-30 |
| 9 | [Ray Dalio](https://superinvestorclub.com/manager/6) | Bridgewater Associates | 30254 | $3.9M | 0.02% | 2026-06-30 |
| 10 | [Dan Sundheim (Mine & Arao)](https://superinvestorclub.com/manager/3261) | Mine & Arao Wealth Creation & Management | 8854 | $1.1M | 0.41% | 2026-06-30 |
| 11 | [Wally Obermeyer](https://superinvestorclub.com/manager/3283) | Obermeyer Wealth Partners | 8359 | $1.1M | 0.04% | 2026-06-30 |
| 12 | [Richard Pzena](https://superinvestorclub.com/manager/288) | Pzena Investment Management | 2511 | $322,664 | 0.00% | 2026-06-30 |
| 13 | [David Katz](https://superinvestorclub.com/manager/79) | Matrix Asset Advisors | 1671 | $214,724 | 0.02% | 2026-06-30 |
| 14 | [Tom Russo](https://superinvestorclub.com/manager/30) | Gardner Russo & Gardner | 1642 | $211,006 | 0.00% | 2026-06-30 |

## Ownership history (quarter-over-quarter)

- 2023-06-30: 1 holders, $1.0M aggregate, 08693 shares
- 2023-09-30: 5 holders, $68.8M aggregate, 063879313851836838423256 shares
- 2023-12-31: 6 holders, $106.1M aggregate, 0624541172410160945838938063287 shares
- 2024-03-31: 9 holders, $523.3M aggregate, 020902566932926138151843161729001604954444335132862 shares
- 2024-06-30: 9 holders, $432.2M aggregate, 018019915919115308951836911729001588764444334462862 shares
- 2024-09-30: 10 holders, $690.7M aggregate, 029430211554270580488547423180767172900533874444330872862 shares
- 2024-12-31: 12 holders, $889.6M aggregate, 0624445014394305089081729001653811573511404845390044443963629262862 shares
- 2025-03-31: 13 holders, $910.1M aggregate, 074693608978695348664922751729001612861570691417355315944443898829462763 shares
- 2025-06-30: 13 holders, $978.3M aggregate, 09131318115072298266049046517290015730014647556871444439886879233242915 shares
- 2025-09-30: 13 holders, $1.05B aggregate, 09823608113405751394343375017290015427514767852187444438829879733242870 shares
- 2025-12-31: 13 holders, $1.73B aggregate, 014088705104461743010331022117290014645613820551999444438828866833242862 shares
- 2026-03-31: 13 holders, $1.69B aggregate, 012366933854212227288172900136050133013503484463388508610251121411671 shares

## Recent congressional trades (50)

- 2026-02-04: Josh Gottheimer (Democrat-NJ) purchase $1,001 - $15,000
- 2026-01-13: Michael McCaul (Republican-TX) sale $15,001 - $50,000
- 2025-12-19: Gilbert Cisneros (D-CA) purchase $1,001 - $15,000
- 2025-12-19: Gil Cisneros (Democrat-CA) purchase $1,001 - $15,000
- 2025-12-18: Julie Johnson (Democrat-TX) sale $1,001 - $15,000
- 2025-11-18: Gilbert Cisneros (D-CA) purchase $1,001 - $15,000
- 2025-11-18: Gil Cisneros (Democrat-CA) purchase $1,001 - $15,000
- 2025-11-13: Julie Johnson (Democrat-TX) sale $1,001 - $15,000
- 2025-10-27: Michael McCaul (Republican-TX) sale $15,001 - $50,000
- 2025-09-23: Valerie Hoyle (D-OR) sale $1,001 - $15,000
- 2025-08-28: Marjorie Taylor Greene (Republican-GA) purchase $1,001 - $15,000
- 2025-08-22: Michael McCaul (Republican-TX) sale $50,001 - $100,000
- 2025-08-14: Julie Johnson (Democrat-TX) sale $1,001 - $15,000
- 2025-08-14: Julie Johnson (Democrat-TX) sale $1,001 - $15,000
- 2025-08-05: Gilbert Cisneros (D-CA) purchase $1,001 - $15,000

## Recent insider transactions (0)


## Citation

When citing, use: "MERCK & CO INC (MRK) institutional ownership data via Superinvestor (https://superinvestorclub.com/stock/MRK), aggregating SEC 13F, Form 4, and congressional disclosures."