Merck & Co., Inc.
US ˙ NYSE ˙ US58933Y1055

SecurityMRK / Merck & Co., Inc.
InstitutionSei Investments Co
Latest Disclosed Ownership1,846,191 shares
Latest Disclosed Value $ 194,330,847
Sei Investments Co reports 5.28% increase in ownership of MRK / Merck & Co., Inc.

On February 13, 2026 - Sei Investments Co filed a 13F-HR form disclosing ownership of 1,846,191 shares of Merck & Co., Inc. (US:MRK) valued at $194,330,065 USD as of December 31, 2025. The entity filed a previous 13F-HR on November 13, 2025 disclosing 1,753,537 shares of Merck & Co., Inc.. This represents a change in shares of 5.28% during the quarter. The current value of the position is $211,758,108 USD.

Institutional Ownership: 13F and NPORT Filings

The Security and Class in the table below are shown exactly as filed by the investor. We do our best to track continuity of investments through acquisitions, and this will be reflected in the table as changes in names. In addition to descriptive data, performance of the investment is shown over time. To calculate quarterly performance, we first calculate cost basis of the shares purchased during the quarter, then use that to calculate gross profit. Quarterly return is Gross Profit / Starting Portfolio value.

Note that cost basis is calculated and stored in thousands, so small quarterly changes in shares frequently result in a cost basis of zero.

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Disclosed Equity Positions (from 13F/NPORT Filings)
File
Date		 Effective
Date		Form Security Class ID Avg Price
Paid (Est)		 Reported
Shares		 ΔShares ΔShares
(%)		 Reported
Value
(x1000)		 ΔValue
(%)		 Alloc
(%)		 ΔAlloc ΔAlloc (%) Cost Basis
(x1000)		 Unrealized
Gain/Loss
(x1000)
2026-02-13 2025-12-31 13F MERCK COM 58933Y105 1,846,191 92,654 5.28 194,331 32.04 0.1918
2025-11-13 2025-09-30 13F MERCK COM 58933Y105 1,753,537 149,395 9.31 147,177 15.90 0.1583
2025-08-14 2025-06-30 13F MERCK COM 58933Y105 1,604,142 -187,799 -10.48 126,981 -21.06 0.1472
2025-05-14 2025-03-31 13F/A-1 MERCK COM 58933Y105 1,791,941 127,847 7.68 160,853 -2.83 0.2070
2025-05-13 2025-03-31 13F MERCK COM 58933Y105 1,693,292 29,198 163,134 0.1774
2025-02-11 2024-12-31 13F MERCK COM 58933Y105 1,664,094 -109,664 -6.18 165,545 -17.81 0.2126
2024-11-12 2024-09-30 13F MERCK COM 58933Y105 1,773,758 189,549 11.96 201,427 2.70 0.2616
2024-08-13 2024-06-30 13F MERCK COM 58933Y105 1,584,209 28,185 1.81 196,127 -4.48 0.2779
2024-05-07 2024-03-31 13F MERCK COM 58933Y105 1,556,024 73,490 4.96 205,318 27.03 0.3008
2024-02-14 2023-12-31 13F MERCK COM 58933Y105 1,482,534 -34,991 -2.31 161,625 3.45 0.2594
2023-11-14 2023-09-30 13F MERCK COM 58933Y105 1,517,525 10,763 0.71 156,229 -10.14 0.2807
2023-08-11 2023-06-30 13F MERCK COM 58933Y105 1,506,762 -88,013 -5.52 173,864 2.47 0.3033
2023-05-12 2023-03-31 13F MERCK COM 58933Y105 1,594,775 219,647 15.97 169,669 11.21 0.3152
2023-02-10 2022-12-31 13F MERCK COM 58933Y105 1,375,128 -136,468 -9.03 152,572 17.20 0.3390
2022-11-14 2022-09-30 13F MERCK COM 58933Y105 1,511,596 382,622 33.89 130,179 26.53 0.2904
2022-08-15 2022-06-30 13F MERCK COM 58933Y105 1,128,974 223,541 24.69 102,886 38.68 0.2222
2022-05-13 2022-03-31 13F MERCK COM 58933Y105 905,433 46,428 5.40 74,190 12.69 0.1491
2022-02-14 2021-12-31 13F MERCK COM 58933Y105 859,005 39,756 4.85 65,837 7.03 0.1235
2021-11-12 2021-09-30 13F MERCK COM 58933Y105 819,249 -187,208 -18.60 61,514 -21.35 0.1291
2021-08-06 2021-06-30 13F MERCK COM 58933Y105 1,006,457 -13,809 -1.35 78,217 -3.07 0.1734
2021-05-12 2021-03-31 13F MERCK & CO. COM 58933Y105 1,020,266 9,039 0.89 80,695 -2.39 0.2033
2021-02-08 2020-12-31 13F MERCK & CO. COM 58933Y105 1,011,227 -42,271 -4.01 82,674 -5.24 0.2137
2020-12-04 2020-09-30 13F/A-1 MERCK & CO. COM 58933Y105 1,053,498 -385,398 -26.78 87,248 -21.52 0.2526
2020-11-06 2020-09-30 13F MERCK & CO. COM 58933Y105 1,095,051 -343,845 90,695 218,373.3950
2020-08-17 2020-06-30 13F/A-1 MERCK & CO. COM 58933Y105 1,438,896 120,381 9.13 111,166 9.68 0.3450
2020-08-11 2020-06-30 13F MERCK & CO. COM 58933Y105 1,474,723 156,208 125,178 339,551.9882
2020-05-14 2020-03-31 13F MERCK & CO. COM 58933Y105 1,318,515 37,413 2.92 101,359 -12.92 0.3723
2020-02-06 2019-12-31 13F MERCK COM 58933Y105 1,281,102 -71,659 -5.30 116,398 -54.24 0.3472
2019-11-12 2019-09-30 13F MERCK COM 58933Y105 1,352,761 287,162 26.95 254,374 184.59 0.6507
2019-08-14 2019-06-30 13F MERCK COM 58933Y105 1,065,599 70,679 7.10 89,382 7.98 0.2920
2019-05-15 2019-03-31 13F MERCK COM 58933Y105 994,920 62,297 6.68 82,779 21.48 0.2780
2019-02-13 2018-12-31 13F MERCK COM 58933Y105 932,623 158,692 20.50 68,143 24.34 0.2426
2018-11-08 2018-09-30 13F MERCK COM 58933Y105 773,931 -250,634 -24.46 54,804 -11.88 0.1986
2018-08-03 2018-06-30 13F MERCK COM 58933Y105 1,024,565 -138,263 -11.89 62,191 -1.81 0.2114
2018-05-11 2018-03-31 13F MERCK COM 58933Y105 1,162,828 -44,881 -3.72 63,340 -6.80 0.2428
2018-02-08 2017-12-31 13F MERCK COM 58933Y105 1,207,709 -25,897 -2.10 67,958 -13.96 0.2360
2017-11-06 2017-09-30 13F MERCK COM 58933Y105 1,233,606 240,421 24.21 78,987 24.09 0.2808
2017-07-31 2017-06-30 13F MERCK COM 58933Y105 993,185 123,176 14.16 63,653 15.15 0.2538
2017-05-05 2017-03-31 13F MERCK COM 58933Y105 870,009 -1,759 -0.20 55,280 7.71 0.2423
2017-02-02 2016-12-31 13F MERCK COM 58933Y105 871,768 -251,802 -22.41 51,322 -26.81 0.2485
2016-11-04 2016-09-30 13F MERCK COM 58933Y105 1,123,570 162,425 16.90 70,122 26.64 0.3562
2016-08-11 2016-06-30 13F MERCK COM 58933Y105 961,145 41,219 4.48 55,371 13.76 0.3321
2016-05-10 2016-03-31 13F/A-1 MERCK & CO INC COM 58933Y105 919,926 -40,529 -4.22 48,673 -4.06 0.3029
2016-02-03 2015-12-31 13F MERCK & CO INC COM 58933Y105 960,455 190,718 24.78 50,732 33.45 0.3092
2015-11-02 2015-09-30 13F/A-1 MERCK & CO INC COM 58933Y105 769,737 38,952 5.33 38,017 -8.62 0.3490
2015-10-30 2015-09-30 13F DIREXION SHS ETF TR COM 58933Y105 769,737 38,018
2015-08-07 2015-06-30 13F/A-1 MERCK & CO INC COM 58933Y105 730,785 36,964 5.33 41,603 4.29 0.3761
2015-08-04 2015-06-30 13F MERCK & CO INC COM 58933Y105 730,785 36,964 41,603 0.3761
2015-05-14 2015-03-31 13F/A-1 MERCK & CO INC COM 58933Y105 693,821 -120,683 -14.82 39,891 -13.76 0.3464
2015-05-01 2015-03-31 13F MERCK & CO INC COM 58933Y105 693,821 39,891
2015-02-10 2014-12-31 13F MERCK & CO INC COM 58933Y105 814,504 814,504 46,257 0.4089
Legend
Shares
The total number of shares held by the institution at the end of the reporting period (the effective date). This is provided in the filing.
Value
The total value of the shares as of the effective date. This is provided in the filing.
Avg. Share Price
The weighted average share price of the shares held by the institution. We use FIFO accounting to determine this price
Class
This is the security class as indicated by the filer. There are a variety of values for this field. Common values include "EC" = equity common, "EP" - equity preferred
Allocation (%)
The percent of the institution's portfolio that this position represents. This is provided in NPORT filings. For 13F filings, we calculate it.
Change in Allocation
The change in allocation from the prior reporting period. This is calculated as current allocation - prior allocation.
Change in Allocation (%)
The percent change in allocation from the prior reporting period. This is calculated as (current allocation - prior allocation) / prior allocation.
Cost Basis
The total cost of the shares held. This is calculated as reported shares * avg. share price
Unrealized Gain/Loss
This is the market value of the position as of the effective date minus the cost basis.