MRK
Merck & Co., Inc. · Healthcare · Drug Manufacturers - General
Momentum inputs (comparable managers):
holder breadth +4.5% ·
share flow +0.2% ·
net new positions +4.3%
— formula
Broad accumulation — rising shares across more holders
All ownership figures: tracked 13F managers only, common-stock positions, reporting period Q3 2024
| Quarter | Holders | Δ | Shares | Reported value | New | Exits |
|---|---|---|---|---|---|---|
| Q2 2026 | 183 | 0 | 1.60B | $205.64B | +4 | −3 |
| Q1 2026 | 185 | +1 | 1.56B | $186.85B | +3 | −3 |
| Q4 2025 | 183 | 0 | 1.68B | $176.48B | +1 | — |
| Q3 2025 | 27 | 0 | 972.48M | $81.66B | +1 | −2 |
| Q2 2025 | 25 | 0 | 887.01M | $70.29B | +1 | −1 |
| Q1 2025 | 22 | -1 | 386.62M | $34.78B | — | −1 |
| Q4 2024 | 23 | -1 | 374.82M | $37.37B | — | −1 |
| Q3 2024 | 23 | +1 | 256.79M | $29.14B | +1 | — |
| Q2 2024 | 22 | — | 256.16M | $31.70B | — | — |
| # | Manager | Shares | Δ shares | Value | Their weight | Held | ||
|---|---|---|---|---|---|---|---|---|
| 1 | Wellington Management ✦ | 75.81M | +4.6% | $8.61B | 1.5% | ▲ Add | 2 | SEC ↗ ×9 |
| 2 | Geode Capital Management ✦ (passive) | 59.16M | +3.7% | $6.70B | 0.5% | ▲ Add | 2 | SEC ↗ ×2 |
| 3 | Norges Bank ✦ (passive) | 33.78M | -0.1% | $3.84B | 0.5% | ▼ Trim | 2 | SEC ↗ |
| 4 | T. Rowe Price ✦ | 22.47M | -9.1% | $2.55B | 0.3% | ▼ Trim | 2 | SEC ↗ ×2 |
| 5 | Capital World Investors ✦ | 15.23M | -0.2% | $1.73B | 0.3% | ▼ Trim | 2 | SEC ↗ |
| 6 | Fisher Asset Management ✦ | 14.65M | +2.7% | $1.66B | 0.7% | ▲ Add | 2 | SEC ↗ |
| 7 | Citadel Advisors ✦ | 7.04M | -14.6% | $799.65M | 0.9% | ▼ Trim | 2 | SEC ↗ ×2 |
| 8 | Arrowstreet Capital ✦ | 6.96M | +12.1% | $790.28M | 0.7% | ▲ Add | 2 | SEC ↗ |
| 9 | D. E. Shaw & Co. ✦ | 6.76M | +184.2% | $767.79M | 1.1% | ▲ Add | 2 | SEC ↗ ×2 |
| 10 | AQR Capital Management ✦ | 3.02M | +36.7% | $343.27M | 0.5% | ▲ Add | 2 | SEC ↗ ×4 |
| 11 | Harris Associates (Oakmark) ✦ | 2.94M | New | $334.21M | 0.6% | New | 1 | SEC ↗ ×2 |
| 12 | Two Sigma Investments ✦ | 1.94M | +30.6% | $219.96M | 0.5% | ▲ Add | 2 | SEC ↗ |
| 13 | Millennium Management ✦ | 1.80M | -81.2% | $204.06M | 0.2% | ▼ Trim | 2 | SEC ↗ |
| 14 | Bridgewater Associates ✦ | 1.55M | -13.8% | $176.50M | 1.0% | ▼ Trim | 2 | SEC ↗ |
| 15 | Adage Capital Partners ✦ | 1.49M | -52.9% | $169.53M | 0.3% | ▼ Trim | 2 | SEC ↗ |
| 16 | Renaissance Technologies ✦ | 1.09M | +21993.1% | $123.31M | 0.2% | ▲ Add | 2 | SEC ↗ |
| 17 | Gotham Asset Management ✦ | 308.92K | +124.4% | $35.08M | 0.4% | ▲ Add | 2 | SEC ↗ |
| 18 | Soros Fund Management ✦ | 300.00K | 0.0% | $34.07M | 1.0% | Held | 2 | SEC ↗ |
| 19 | Fairfax Financial ✦ | 172.90K | 0.0% | $19.63M | 1.8% | Held | 2 | SEC ↗ |
| 20 | Dodge & Cox ✦ | 158.25K | -0.4% | $17.97M | 0.0% | ▼ Trim | 2 | SEC ↗ |
| 21 | GAMCO Investors ✦ | 80.94K | +5.4% | $9.19M | 0.1% | ▲ Add | 2 | SEC ↗ |
| 22 | PRIMECAP Management ✦ | 66.80K | -8.2% | $7.59M | 0.0% | ▼ Trim | 2 | SEC ↗ |
| 23 | Marshall Wace ✦ | 3.36K | -99.9% | $381,561 | 0.0% | ▼ Trim | 2 | SEC ↗ |
“Their weight” = the position's share of that manager's reported 13F equity value — the conviction measure. ✦ = curated manager.
New buyers
| Harris Associates (Oakmark) | $334.21M | 0.6% |
Exited
| No tracked exits this quarter. |
Full-market context: across ALL 13F filers (SEC structured data, Q1 2026): 3,742 holders, 1.88B shares, $215.80B reported. This is a different, older period than the tracked-universe figures above and the two are never mixed.
What else this security's tracked holders most often hold — shared-ownership counts, not fundamental relationships.
Open-market purchases (P)
No open-market insider purchases in our coverage window.
Open-market sales (S)
Officer · 10.00K sh · $1.35M
Officer · 80.31K sh · $10.72M
Officer · 11.10K sh · $1.46M
Officer · 600 sh · $79,222
Officer · 5.43K sh · $718,261
Officer · 7.41K sh · $973,165
Officer · 20.78K sh · $2.71M
Officer · 805 sh · $105,472
Officer · 4.95K sh · $643,993
Officer · 300 sh · $39,307
Awards, exercises and tax withholding are never counted as buys or sales here. Methodology