Merck & Co., Inc.
MX ˙ BMV ˙ US58933Y1055
SecurityMX:MRK / Merck & Co., Inc.
InstitutionWashington Trust Bank
Latest Disclosed Ownership132,592 shares
Latest Disclosed Value $ 15,949,492
Washington Trust Bank reports 10.55% decrease in ownership of MRK / Merck & Co., Inc.

On May 7, 2026 - Washington Trust Bank filed a 13F-HR form disclosing ownership of 132,592 shares of Merck & Co., Inc. (MX:MRK) valued at $15,949,492 USD as of March 31, 2026. The entity filed a previous 13F-HR on February 4, 2026 disclosing 148,235 shares of Merck & Co., Inc.. This represents a change in shares of -10.55% 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)
2026-05-07 2026-03-31 13F MERCK COM 58933Y105 132,592 -15,643 -10.55 15,949 2.22 0.9706
2026-02-04 2025-12-31 13F MERCK COM 58933Y105 148,235 -1,846 -1.23 15,603 23.87 1.0931
2025-10-24 2025-09-30 13F MERCK COM 58933Y105 150,081 -7,846 -4.97 12,596 0.76 0.9231
2025-08-06 2025-06-30 13F MERCK COM 58933Y105 157,927 19,055 13.72 12,502 0.29 1.0529
2025-04-30 2025-03-31 13F MERCK COM 58933Y105 138,872 2,326 1.70 12,465 -8.23 1.2486
2025-02-11 2024-12-31 13F Merck COM 58933Y105 136,546 3,428 2.58 13,584 -10.14 1.3047
2024-10-31 2024-09-30 13F Merck COM 58933Y105 133,118 -1,322 -0.98 15,117 -9.18 1.4472
2024-07-29 2024-06-30 13F Merck COM 58933Y105 134,440 -3,600 -2.61 16,644 -8.63 1.6461
2024-05-14 2024-03-31 13F Merck COM 58933Y105 138,040 -3,117 -2.21 18,214 18.36 1.7361
2024-02-14 2023-12-31 13F Merck COM 58933Y105 141,157 -1,781 -1.25 15,389 4.57 1.3636
2023-11-06 2023-09-30 13F Merck COM 58933Y105 142,938 -3,235 -2.21 14,715 -12.75 1.5372
2023-08-10 2023-06-30 13F Merck COM 58933Y105 146,173 956 0.66 16,867 9.17 1.7218
2023-05-15 2023-03-31 13F Merck COM 58933Y105 145,217 19,625 15.63 15,450 118,738.46 1.6528
2023-02-06 2022-12-31 13F Merck COM 58933Y105 125,592 103,896 478.87 14 -99.30 1.5803
2022-11-16 2022-09-30 13F Merck COM 58933Y105 21,696 1,454 7.18 1,868 1.25 0.2375
2022-08-04 2022-06-30 13F Merck COM 58933Y105 20,242 -1,487 -6.84 1,845 3.48 0.2369
2022-05-13 2022-03-31 13F Merck COM 58933Y105 21,729 -347 -1.57 1,783 5.38 0.2063
2022-02-09 2021-12-31 13F Merck COM 58933Y105 22,076 1,281 6.16 1,692 8.32 0.1636
2021-10-27 2021-09-30 13F Merck COM 58933Y105 20,795 3,883 22.96 1,562 18.69 0.1825
2021-07-28 2021-06-30 13F Merck COM 58933Y105 16,912 -138 -0.81 1,316 0.15 0.1559
2021-04-22 2021-03-31 13F Merck COM 58933Y105 17,050 856 5.29 1,314 -0.83 0.1619
2021-02-08 2020-12-31 13F Merck COM 58933Y105 16,194 134 0.83 1,325 -0.60 0.1729
2020-11-12 2020-09-30 13F Merck COM 58933Y105 16,060 -565 -3.40 1,333 3.65 0.1972
2020-07-29 2020-06-30 13F Merck COM 58933Y105 16,625 -232 -1.38 1,286 -0.85 0.2046
2020-05-01 2020-03-31 13F Merck COM 58933Y105 16,857 -1,251 -6.91 1,297 -21.25 0.2488
2020-01-29 2019-12-31 13F Merck COM 58933Y105 18,108 86 0.48 1,647 8.57 0.2342
2019-10-29 2019-09-30 13F Merck COM 58933Y105 18,022 -956 -5.04 1,517 -4.65 0.2482
2019-07-26 2019-06-30 13F Merck COM 58933Y105 18,978 -910 -4.58 1,591 -3.81 0.2588
2019-04-09 2019-03-31 13F MERCK COM 58933Y105 19,888 -8,096 -28.93 1,654 -22.67 0.2636
2019-02-13 2018-12-31 13F MERCK COM 58933Y105 27,984 -1,176 -4.03 2,139 3.43 0.2809
2018-11-14 2018-09-30 13F MERCK COM 58933Y105 29,160 -159 -0.54 2,068 16.18 0.3072
2018-07-03 2018-06-30 13F MERCK COM 58933Y105 29,319 -7,237 -19.80 1,780 -10.60 0.2479
2018-04-03 2018-03-31 13F Merck COM 58933Y105 36,556 -2,295 -5.91 1,991 -8.96 0.2856
2018-01-03 2017-12-31 13F Merck COM 58933Y105 38,851 -17 -0.04 2,187 -12.10 0.3198
2017-10-05 2017-09-30 13F Merck COM 58933Y105 38,868 1,479 3.96 2,488 3.84 0.3946
2017-07-20 2017-06-30 13F Merck COM 58933Y105 37,389 -365 -0.97 2,396 -0.13 0.5140
2017-04-18 2017-03-31 13F Merck COM 58933Y105 37,754 3,563 10.42 2,399 19.18 0.5178
2017-01-17 2016-12-31 13F Merck COM 58933Y105 34,191 -220 -0.64 2,013 -6.28 0.4538
2016-10-04 2016-09-30 13F Merck COM 58933Y105 34,411 2,888 9.16 2,148 18.28 0.5167
2016-07-07 2016-06-30 13F Merck COM 58933Y105 31,523 -305 -0.96 1,816 7.84 0.4701
2016-04-25 2016-03-31 13F Merck COM 58933Y105 31,828 333 1.06 1,684 1.20 0.4352
2016-01-21 2015-12-31 13F Merck COM 58933Y105 31,495 2,428 8.35 1,664 15.88 0.3624
2015-10-07 2015-09-30 13F Merck Common Stock 58933Y105 29,067 1,515 5.50 1,436 -8.48 0.3817
2015-07-10 2015-06-30 13F Merck Common Stock 58933Y105 27,552 -18,955 -40.76 1,569 -41.30 0.3828
2015-04-17 2015-03-31 13F Merck Common Stock 58933Y105 46,507 10,662 29.74 2,673 31.29 0.6441
2015-01-15 2014-12-31 13F Merck Common Stock 58933Y105 35,845 -1,196 -3.23 2,036 -7.29 0.5314
2014-11-21 2014-09-30 13F Merck Common Stock 58933Y105 37,041 -3,662 -9.00 2,196 -6.75 0.6890
2014-08-08 2014-06-30 13F Merck Common Stock 58933Y105 40,703 1,770 4.55 2,355 6.56 0.4788
2014-05-15 2014-03-31 13F Merck Common Stock 58933Y105 38,933 38,933 2,210 0.4667
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.