Merck & Co., Inc.
MX ˙ BMV ˙ US58933Y1055
SecurityMX:MRK / Merck & Co., Inc.
InstitutionRiver Wealth Advisors LLC
Latest Disclosed Ownership93,102 shares
Latest Disclosed Value $ 11,199,267
River Wealth Advisors LLC reports 0.79% decrease in ownership of MRK / Merck & Co., Inc.

On May 13, 2026 - River Wealth Advisors LLC filed a 13F-HR form disclosing ownership of 93,102 shares of Merck & Co., Inc. (MX:MRK) valued at $11,199,267 USD as of March 31, 2026. The entity filed a previous 13F-HR on February 13, 2026 disclosing 93,839 shares of Merck & Co., Inc.. This represents a change in shares of -0.79% 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 93,102 -737 -0.79 11,199 13.38 1.2862
2026-02-13 2025-12-31 13F MERCK COM 58933Y105 93,839 11,915 14.54 9,877 43.67 1.1077
2025-11-12 2025-09-30 13F MERCK COM 58933Y105 81,924 15,906 24.09 6,876 31.55 0.8039
2025-08-13 2025-06-30 13F MERCK COM 58933Y105 66,018 11,853 21.88 5,226 7.51 0.6496
2025-05-14 2025-03-31 13F MERCK COM 58933Y105 54,165 7,648 16.44 4,862 5.06 0.6757
2025-02-13 2024-12-31 13F MERCK COM 58933Y105 46,517 2,199 4.96 4,627 -8.05 0.6134
2024-11-12 2024-09-30 13F MERCK COM 58933Y105 44,318 3,665 9.02 5,033 0.00 0.6708
2024-08-13 2024-06-30 13F MERCK COM 58933Y105 40,653 3,205 8.56 5,033 1.84 0.7218
2024-05-14 2024-03-31 13F MERCK COM 58933Y105 37,448 3,026 8.79 4,941 31.69 0.7183
2024-02-13 2023-12-31 13F MERCK COM 58933Y105 34,422 1,051 3.15 3,753 9.23 0.5992
2023-11-13 2023-09-30 13F MERCK COM 58933Y105 33,371 3,704 12.49 3,436 0.35 0.6146
2023-08-09 2023-06-30 13F MERCK COM 58933Y105 29,667 3,219 12.17 3,423 21.69 0.5809
2023-05-11 2023-03-31 13F MERCK COM 58933Y105 26,448 3,701 16.27 2,814 11.49 0.5120
2023-02-10 2022-12-31 13F MERCK COM 58933Y105 22,747 3,892 20.64 2,524 55.36 0.4862
2022-11-14 2022-09-30 13F MERCK COM 58933Y105 18,855 3,780 25.07 1,624 18.20 0.3500
2022-08-10 2022-06-30 13F MERCK COM 58933Y105 15,075 3,028 25.13 1,374 38.93 0.2532
2022-05-09 2022-03-31 13F MERCK COM 58933Y105 12,047 1,557 14.84 989 23.01 0.1579
2022-02-11 2021-12-31 13F MERCK COM 58933Y105 10,490 1,467 16.26 804 18.58 0.1247
2021-11-12 2021-09-30 13F MERCK COM 58933Y105 9,023 627 7.47 678 3.83 0.1161
2021-08-06 2021-06-30 13F MERCK COM 58933Y105 8,396 -240 -2.78 653 -1.95 0.1143
2021-05-11 2021-03-31 13F MERCK & CO. COM 58933Y105 8,636 706 8.90 666 2.62 0.1250
2021-02-16 2020-12-31 13F MERCK & CO. COM 58933Y105 7,930 1,034 14.99 649 13.46 0.1403
2020-11-10 2020-09-30 13F MERCK & CO. COM 58933Y105 6,896 1,552 29.04 572 38.50 0.1493
2020-08-11 2020-06-30 13F MERCK & CO. COM 58933Y105 5,344 120 2.30 413 2.74 0.1254
2020-05-05 2020-03-31 13F MERCK & CO. COM 58933Y105 5,224 155 3.06 402 -12.80 0.1606
2020-02-07 2019-12-31 13F MERCK COM 58933Y105 5,069 -743 -12.78 461 -5.73 0.1559
2019-10-29 2019-09-30 13F MERCK COM 58933Y105 5,812 -545 -8.57 489 -8.26 0.1848
2019-07-30 2019-06-30 13F MERCK COM 58933Y105 6,357 4 0.06 533 0.95 0.2080
2019-05-07 2019-03-31 13F MERCK COM 58933Y105 6,353 -137 -2.11 528 6.45 0.2211
2019-01-25 2018-12-31 13F MERCK COM 58933Y105 6,490 4 0.06 496 7.83 0.2205
2018-11-09 2018-09-30 13F MERCK COM 58933Y105 6,486 -342 -5.01 460 11.11 0.1696
2018-08-13 2018-06-30 13F MERCK COM 58933Y105 6,828 -944 -12.15 414 -2.13 0.1610
2018-05-02 2018-03-31 13F MERCK COM 58933Y105 7,772 -2,935 -27.41 423 -29.73 0.1783
2018-02-09 2017-12-31 13F MERCK COM 58933Y105 10,707 2,570 31.58 602 15.55 0.2503
2017-11-06 2017-09-30 13F MERCK COM 58933Y105 8,137 -745 -8.39 521 -8.44 0.2357
2017-07-28 2017-06-30 13F MERCK COM 58933Y105 8,882 -116 -1.29 569 -0.52 0.2649
2017-05-12 2017-03-31 13F MERCK COM 58933Y105 8,998 -1,248 -12.18 572 -5.14 0.2776
2017-02-17 2016-12-31 13F MERCK COM 58933Y105 10,246 -1,740 -14.52 603 -19.39 0.3051
2016-11-02 2016-09-30 13F MERCK COM 58933Y105 11,986 -4,362 -26.68 748 -20.59 0.4135
2016-08-05 2016-06-30 13F MERCK COM 58933Y105 16,348 -1,195 -6.81 942 1.51 0.5408
2016-04-27 2016-03-31 13F MERCK & CO INC COM 58933Y105 17,543 390 2.27 928 2.43 0.5545
2016-01-19 2015-12-31 13F MERCK & CO INC COM 58933Y105 17,153 9,252 117.10 906 132.31 0.5739
2015-10-26 2015-09-30 13F MERCK & CO INC COM 58933Y105 7,901 108 1.39 390 -12.16 0.2678
2015-07-13 2015-06-30 13F MERCK & CO INC COM 58933Y105 7,793 -562 -6.73 444 -7.50 0.2822
2015-05-15 2015-03-31 13F MERCK & CO INC COM 58933Y105 8,355 8,355 480 0.2971
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.