Merck & Co., Inc.
MX ˙ BMV ˙ US58933Y1055
SecurityMX:MRK / Merck & Co., Inc.
InstitutionAdvisors Asset Management, Inc.
Latest Disclosed Ownership349,476 shares
Latest Disclosed Value $ 42,038,468
Advisors Asset Management, Inc. reports 1.98% increase in ownership of MRK / Merck & Co., Inc.

On May 15, 2026 - Advisors Asset Management, Inc. filed a 13F-HR form disclosing ownership of 349,476 shares of Merck & Co., Inc. (MX:MRK) valued at $42,038,468 USD as of March 31, 2026. The entity filed a previous 13F-HR on February 12, 2026 disclosing 342,689 shares of Merck & Co., Inc.. This represents a change in shares of 1.98% during the quarter.

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)
2026-05-15 2026-03-31 13F MERCK COM 58933Y105 349,476 6,787 1.98 42,038 16.54 0.6980
2026-02-12 2025-12-31 13F MERCK COM 58933Y105 342,689 2,380 0.70 36,071 26.29 0.6056
2025-11-06 2025-09-30 13F MERCK COM 58933Y105 340,309 43,520 14.66 28,562 21.58 0.4848
2025-08-12 2025-06-30 13F MERCK COM 58933Y105 296,789 9,009 3.13 23,494 -9.05 0.4206
2025-05-15 2025-03-31 13F MERCK COM 58933Y105 287,780 31,065 12.10 25,831 1.15 0.4853
2025-02-10 2024-12-31 13F MERCK COM 58933Y105 256,715 -11,861 -4.42 25,538 -16.27 0.4704
2024-11-08 2024-09-30 13F MERCK COM 58933Y105 268,576 -2,147 -0.79 30,499 -9.00 0.5602
2024-08-14 2024-06-30 13F MERCK COM 58933Y105 270,723 -37,594 -12.19 33,516 -17.62 0.6537
2024-05-14 2024-03-31 13F MERCK COM 58933Y105 308,317 -28,562 -8.48 40,682 10.77 0.7819
2024-02-14 2023-12-31 13F MERCK COM 58933Y105 336,879 -80,867 -19.36 36,727 -14.60 0.7498
2023-11-14 2023-09-30 13F MERCK COM 58933Y105 417,746 -29,978 -6.70 43,007 -16.76 0.9278
2023-08-14 2023-06-30 13F MERCK COM 58933Y105 447,724 -84,956 -15.95 51,663 -8.84 1.0555
2023-05-12 2023-03-31 13F MERCK COM 58933Y105 532,680 -73,126 -12.07 56,672 -15.69 1.1529
2023-02-13 2022-12-31 13F MERCK COM 58933Y105 605,806 -68,669 -10.18 67,214 15.71 1.3847
2022-11-08 2022-09-30 13F MERCK & CO. COM 58933Y105 674,475 -54,663 -7.50 58,086 -12.62 1.2212
2022-08-08 2022-06-30 13F MERCK COM 58933Y105 729,138 -32,585 -4.28 66,476 6.36 1.2610
2022-05-17 2022-03-31 13F MERCK COM 58933Y105 761,723 34,602 4.76 62,499 12.15 0.9624
2022-02-15 2021-12-31 13F MERCK & CO. COM 58933Y105 727,121 61,521 9.24 55,727 11.47 0.7956
2021-11-12 2021-09-30 13F MERCK COM 58933Y105 665,600 89,803 15.60 49,993 11.64 0.7602
2021-07-30 2021-06-30 13F MERCK COM 58933Y105 575,797 182,204 46.29 44,780 47.58 0.6605
2021-05-07 2021-03-31 13F MERCK & CO. COM 58933Y105 393,593 100,428 34.26 30,342 26.53 0.4717
2021-02-12 2020-12-31 13F MERCK & CO. COM 58933Y105 293,165 107,727 58.09 23,981 55.90 0.3966
2020-11-16 2020-09-30 13F MERCK & CO. COM 58933Y105 185,438 37,383 25.25 15,382 34.35 0.2844
2020-08-12 2020-06-30 13F MERCK & CO. COM 58933Y105 148,055 -9,534 -6.05 11,449 -5.58 0.2229
2020-05-15 2020-03-31 13F MERCK COM 58933Y105 157,589 -75,990 -32.53 12,125 -42.93 0.2884
2020-05-20 2019-12-31 13F/A-1 MERCK COM 58933Y105 233,579 -46,288 -16.54 21,244 -9.83 0.3725
2020-02-14 2019-12-31 13F MERCK COM 58933Y105 233,579 -46,288 23,749 210,201.1041
2019-11-14 2019-09-30 13F MERCK COM 58933Y105 279,867 -131,294 -31.93 23,559 -31.67 0.4339
2019-11-14 2019-06-30 13F/A-1 MERCK & CO. COM 58933Y105 411,161 -127,623 -23.69 34,476 -23.06 0.6219
2019-08-14 2019-06-30 13F MERCK COM 58933Y105 411,161 -127,623 34,476
2019-05-15 2019-03-31 13F MERCK & CO. COM 58933Y105 538,784 -107,416 -16.62 44,811 -9.25 0.7975
2019-02-06 2018-12-31 13F/A-1 MERCK COM 58933Y105 646,200 -4,708 -0.72 49,376 6.93 0.9941
2019-01-31 2018-12-31 13F MERCK COM 58933Y105 646,200 -4,708 49,376
2018-11-15 2018-09-30 13F MERCK COM 58933Y105 650,908 -525 -0.08 46,175 16.77 0.7548
2018-08-22 2018-06-30 13F/A-1 MERCK COM 58933Y105 651,433 45,964 7.59 39,542 20.44 0.6716
2018-08-15 2018-06-30 13F MERCK COM 58933Y105 651,433 45,964 39,542
2018-05-15 2018-03-31 13F MERCK COM 58933Y105 605,469 30,050 5.22 32,831 1.40 0.5501
2018-02-13 2017-12-31 13F MERCK COM 58933Y105 575,419 14,336 2.56 32,379 -9.87 0.5323
2017-11-07 2017-09-30 13F MERCK COM 58933Y105 561,083 -113,297 -16.80 35,926 -16.88 0.6018
2017-08-02 2017-06-30 13F MERCK COM 58933Y105 674,380 -67,409 -9.09 43,221 -8.30 0.7224
2017-05-02 2017-03-31 13F MERCK COM 58933Y105 741,789 -86,113 -10.40 47,133 -8.78 0.7899
2016-10-31 2016-09-30 13F MERCK COM 58933Y105 827,902 967 0.12 51,669 8.46 0.8474
2016-08-08 2016-06-30 13F MERCK COM 58933Y105 826,935 -34,444 -4.00 47,640 4.53 0.7723
2016-05-16 2016-03-31 13F MERCK & CO INC COM 58933Y105 861,379 -40,099 -4.45 45,576 -4.28 0.7583
2016-02-10 2015-12-31 13F MERCK & CO INC COM 58933Y105 901,478 56,780 6.72 47,616 14.13 0.7555
2015-11-16 2015-09-30 13F MERCK & CO INC COM 58933Y105 844,698 -136,840 -13.94 41,720 -25.34 0.6653
2015-08-11 2015-06-30 13F MERCK & CO INC COM 58933Y105 981,538 -103,669 -9.55 55,879 -10.42 0.7669
2015-05-13 2015-03-31 13F MERCK & CO INC COM 58933Y105 1,085,207 -61,561 -5.37 62,378 -4.22 0.8308
2015-02-05 2014-12-31 13F MERCK & CO INC COM 58933Y105 1,146,768 -116,151 -9.20 65,125 -13.01 0.8731
2014-11-13 2014-09-30 13F MERCK & CO INC COM 58933Y105 1,262,919 -100,941 -7.40 74,866 -5.11 1.0325
2014-08-14 2014-06-30 13F MERCK & CO INC COM 58933Y105 1,363,860 -27,372 -1.97 78,899 -0.10 1.0938
2014-05-15 2014-03-31 13F MERCK & CO INC COM 58933Y105 1,391,232 28,177 2.07 78,980 15.77 1.1975
2014-02-03 2013-12-31 13F MERCK & CO INC COM 58933Y105 1,363,055 17,719 1.32 68,221 6.51 1.0996
2013-11-15 2013-09-30 13F MERCK & CO INC COM 58933Y105 1,345,336 61,213 4.77 64,051 7.38 1.1371
2013-08-14 2013-06-30 13F MERCK & CO INC COM 58933Y105 1,284,123 1,284,123 59,648 1.1269
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.