Merck & Co., Inc.
MX ˙ BMV ˙ US58933Y1055
SecurityMX:MRK / Merck & Co., Inc.
InstitutionAdviser Investments LLC
Latest Disclosed Ownership110,763 shares
Latest Disclosed Value $ 13,323,674
Adviser Investments LLC reports 7.68% increase in ownership of MRK / Merck & Co., Inc.

On May 13, 2026 - Adviser Investments LLC filed a 13F-HR form disclosing ownership of 110,763 shares of Merck & Co., Inc. (MX:MRK) valued at $13,323,674 USD as of March 31, 2026. The entity filed a previous 13F-HR on February 12, 2026 disclosing 102,862 shares of Merck & Co., Inc.. This represents a change in shares of 7.68% 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)
2026-05-13 2026-03-31 13F MERCK COM 58933Y105 110,763 7,901 7.68 13,324 23.05 0.1458
2026-02-12 2025-12-31 13F MERCK COM 58933Y105 102,862 -8,889 -7.95 10,827 15.44 0.1183
2025-11-10 2025-09-30 13F MERCK COM 58933Y105 111,751 -44,217 -28.35 9,379 -24.03 0.1065
2025-08-06 2025-06-30 13F MERCK COM 58933Y105 155,968 -392,016 -71.54 12,346 -74.90 0.1545
2025-05-13 2025-03-31 13F MERCK COM 58933Y105 547,984 1,394 0.26 49,187 -9.54 0.6202
2025-02-12 2024-12-31 13F MERCK COM 58933Y105 546,590 207,497 61.19 54,375 41.21 0.6700
2024-11-08 2024-09-30 13F MERCK COM 58933Y105 339,093 54,683 19.23 38,508 9.36 0.4805
2024-08-12 2024-06-30 13F MERCK COM 58933Y105 284,410 191 0.07 35,210 -6.11 0.4643
2024-04-29 2024-03-31 13F MERCK COM 58933Y105 284,219 -9,463 -3.22 37,503 17.13 0.5047
2024-02-01 2023-12-31 13F MERCK COM 58933Y105 293,682 159,612 119.05 32,017 131.97 0.4567
2023-10-11 2023-09-30 13F MERCK COM 58933Y105 134,070 6,787 5.33 13,802 -6.03 0.3007
2023-08-04 2023-06-30 13F MERCK COM 58933Y105 127,283 27,396 27.43 14,687 38.20 0.3214
2023-04-26 2023-03-31 13F MERCK COM 58933Y105 99,887 1,873 1.91 10,627 -2.38 0.2550
2023-01-19 2022-12-31 13F MERCK COM 58933Y105 98,014 3,833 4.07 10,886 34.21 0.2707
2022-10-14 2022-09-30 13F MERCK COM 58933Y105 94,181 1,410 1.52 8,111 -4.10 0.5713
2022-07-14 2022-06-30 13F MERCK COM 58933Y105 92,771 3,033 3.38 8,458 14.87 0.5709
2022-05-04 2022-03-31 13F MERCK COM 58933Y105 89,738 6,867 8.29 7,363 15.93 0.4765
2022-01-31 2021-12-31 13F MERCK COM 58933Y105 82,871 -18,120 -17.94 6,351 -16.27 0.4263
2021-11-05 2021-09-30 13F MERCK COM 58933Y105 100,991 534 0.53 7,585 -2.92 0.5660
2021-07-09 2021-06-30 13F MERCK COM 58933Y105 100,457 3,605 3.72 7,813 4.65 0.5830
2021-05-05 2021-03-31 13F MERCK & CO. COM 58933Y105 96,852 16,330 20.28 7,466 13.34 0.6024
2021-01-26 2020-12-31 13F MERCK & CO. COM 58933Y105 80,522 26,138 48.06 6,587 46.02 0.5843
2020-11-13 2020-09-30 13F MERCK & CO. COM 58933Y105 54,384 -8 -0.01 4,511 7.25 0.4745
2020-08-03 2020-06-30 13F MERCK & CO. COM 58933Y105 54,392 39,793 272.57 4,206 274.53 0.5142
2020-04-08 2020-03-31 13F MERCK & CO. COM 58933Y105 14,599 3,580 32.49 1,123 12.08 0.1591
2020-02-07 2019-12-31 13F MERCK COM 58933Y105 11,019 68 0.62 1,002 8.68 0.0994
2019-11-13 2019-09-30 13F MERCK COM 58933Y105 10,951 459 4.37 922 4.77 0.0974
2019-08-12 2019-06-30 13F MERCK COM 58933Y105 10,492 -992 -8.64 880 -7.85 0.0945
2019-05-07 2019-03-31 13F MERCK COM 58933Y105 11,484 0 0.00 955 8.77 0.1092
2019-01-25 2018-12-31 13F MERCK COM 58933Y105 11,484 1,759 18.09 878 27.25 0.1155
2018-11-13 2018-09-30 13F MERCK COM 58933Y105 9,725 -333 -3.31 690 12.93 0.0773
2018-08-02 2018-06-30 13F MERCK COM 58933Y105 10,058 6,873 215.79 611 253.18 0.0682
2018-05-14 2018-03-31 13F MERCK COM 58933Y105 3,185 -8,918 -73.68 173 -74.60 0.0223
2018-02-12 2017-12-31 13F MERCK COM 58933Y105 12,103 -870 -6.71 681 -18.05 0.0766
2017-10-23 2017-09-30 13F MERCK COM 58933Y105 12,973 791 6.49 831 6.40 0.0937
2017-08-11 2017-06-30 13F MERCK COM 58933Y105 12,182 216 1.81 781 2.76 0.0958
2017-04-25 2017-03-31 13F MERCK COM 58933Y105 11,966 11,966 760 0.0997
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.