MERCK & CO. INC. · CUSIP 58933Y105 · CIK 1423053
As of 2026-06-30, CITADEL ADVISORS LLC reported 1.93M MRK (shares), valued at $248.48M, or 0.14% of its reported non-derivative portfolio. Filed 2026-09-02.
Verify history & sources →Shares decreased 49.40%; reported value decreased 45.94%, and weight changed -0.19 pp. Weight depends on both the security valuation and total portfolio value, not trade proceeds.
Left: % · Right: Shares · Independently scaled axes
Exact data and methodology
Axes scale independently; a crossing does not mean equal values. Weight uses each quarter's total reported non-derivative value. Same CUSIP; missing quarters are gaps, not zero. Revised history may include later disclosures.
| Quarter | Weight | Quantity | Source |
|---|---|---|---|
| Q2 2026 | 0.14% | 1,933,667 | SEC filing ↗Filed Sep 2, 2026Amended |
| Q1 2026 | 0.33% | 3,821,227 | SEC filing ↗Filed May 15, 2026 |
| Q4 2025 | 0.49% | 6,821,331 | SEC filing ↗Filed Feb 17, 2026 |
| Q3 2025 | 0.07% | 968,054 | SEC filing ↗Filed Nov 14, 2025 |
| Q2 2025 | Not reported | Not reported | — |
| Q1 2025 | 0.18% | 2,048,739 | SEC filing ↗Filed May 15, 2025 |
| Q4 2024 | 0.49% | 5,281,710 | SEC filing ↗Filed Feb 14, 2025 |
| Q3 2024 | 0.83% | 7,041,689 | SEC filing ↗Filed Nov 14, 2024 |
| Q2 2024 | 1.00% | 8,242,067 | SEC filing ↗Filed Aug 14, 2024 |
| Q1 2024 | 0.96% | 7,575,220 | SEC filing ↗Filed May 15, 2024 |
| Q4 2023 | 0.69% | 6,318,171 | SEC filing ↗Filed Feb 14, 2024 |
| Q3 2023 | 0.74% | 6,677,107 | SEC filing ↗Filed Nov 14, 2023 |
History & evidence by quarter
| Quarter | Weight | Quantity | Value | Change explained | Source |
|---|---|---|---|---|---|
| Q3 2023 | 0.74% | 6,677,107 | $687.41M | The prior quarter is outside the free window. Sign in for the comparison. | SEC filing ↗ Filed Nov 14, 2023 |
| Q4 2023 | 0.69% | 6,318,171 | $688.81M | Shares decreased 5.38%; reported value increased 0.20%, and weight changed -0.05 pp. Weight depends on both the security valuation and total portfolio value, not trade proceeds. | SEC filing ↗ Filed Feb 14, 2024 |
| Q1 2024 | 0.96% | 7,575,220 | $999.55M | Shares increased 19.90%; reported value increased 45.11%, and weight changed +0.27 pp. Weight depends on both the security valuation and total portfolio value, not trade proceeds. | SEC filing ↗ Filed May 15, 2024 |
| Q2 2024 | 1.00% | 8,242,067 | $1.02B | Shares increased 8.80%; reported value increased 2.08%, and weight changed +0.04 pp. Weight depends on both the security valuation and total portfolio value, not trade proceeds. | SEC filing ↗ Filed Aug 14, 2024 |
| Q3 2024 | 0.83% | 7,041,689 | $799.65M | Shares decreased 14.56%; reported value decreased 21.63%, and weight changed -0.17 pp. Weight depends on both the security valuation and total portfolio value, not trade proceeds. | SEC filing ↗ Filed Nov 14, 2024 |
| Q4 2024 | 0.49% | 5,281,710 | $525.42M | Shares decreased 24.99%; reported value decreased 34.29%, and weight changed -0.34 pp. Weight depends on both the security valuation and total portfolio value, not trade proceeds. | SEC filing ↗ Filed Feb 14, 2025 |
| Q1 2025 | 0.18% | 2,048,739 | $183.89M | Shares decreased 61.21%; reported value decreased 65.00%, and weight changed -0.31 pp. Weight depends on both the security valuation and total portfolio value, not trade proceeds. | SEC filing ↗ Filed May 15, 2025 |
| Q2 2025 | Not reported | — | — | This security is absent from this quarter's filing; a missing record is not treated as zero holdings. | — |
| Q3 2025 | 0.07% | 968,054 | $81.25M | A comparable prior-quarter record is unavailable; changes are not inferred. | SEC filing ↗ Filed Nov 14, 2025 |
| Q4 2025 | 0.49% | 6,821,331 | $718.01M | Shares increased 604.64%; reported value increased 783.72%, and weight changed +0.42 pp. Weight depends on both the security valuation and total portfolio value, not trade proceeds. | SEC filing ↗ Filed Feb 17, 2026 |
| Q1 2026 | 0.33% | 3,821,227 | $459.66M | Shares decreased 43.98%; reported value decreased 35.98%, and weight changed -0.16 pp. Weight depends on both the security valuation and total portfolio value, not trade proceeds. | SEC filing ↗ Filed May 15, 2026 |
| Q2 2026 | 0.14% | 1,933,667 | $248.48M | Shares decreased 49.40%; reported value decreased 45.94%, and weight changed -0.19 pp. Weight depends on both the security valuation and total portfolio value, not trade proceeds. | SEC filing ↗ Filed Sep 2, 2026 |
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Figures are as reported to the SEC and merged with later amendments where Akkru could match them. Preview limits apply to what is listed, not to the totals, which come from the complete reported data. Nothing is zero-filled: a missing quarter or month is shown as missing.