Merck & Co., Inc.
MX ˙ BMV ˙ US58933Y1055
SecurityMX:MRK / Merck & Co., Inc.
InstitutionTufton Capital Management
Latest Disclosed Ownership99,132 shares
Latest Disclosed Value $ 11,924
Tufton Capital Management reports 1.13% decrease in ownership of MRK / Merck & Co., Inc.

On May 12, 2026 - Tufton Capital Management filed a 13F-HR form disclosing ownership of 99,132 shares of Merck & Co., Inc. (MX:MRK) valued at $11,924 USD as of March 31, 2026. The entity filed a previous 13F-HR on January 28, 2026 disclosing 100,265 shares of Merck & Co., Inc.. This represents a change in shares of -1.13% 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)
2026-05-12 2026-03-31 13F MERCK & CO INC COM COM 58933Y105 99,132 -1,133 -1.13 12 10.00 2.1693
2026-01-28 2025-12-31 13F MERCK COM 58933Y105 100,265 -917 -0.91 11 25.00 1.8447
2025-10-31 2025-09-30 13F MERCK COM 58933Y105 101,182 -455 -0.45 8 0.00 1.5137
2025-08-05 2025-06-30 13F MERCK COM 58933Y105 101,637 -3,160 -3.02 8 -99.91 1.5296
2025-05-06 2025-03-31 13F MERCK COM 58933Y105 104,797 113 0.11 9,407 -9.68 1.8119
2025-02-05 2024-12-31 13F MERCK COM 58933Y105 104,684 565 0.54 10,414 -11.92 1.9698
2024-11-08 2024-09-30 13F MERCK COM 58933Y105 104,119 -1,250 -1.19 11,824 -9.36 2.2166
2024-07-31 2024-06-30 13F MERCK COM 58933Y105 105,369 -685 -0.65 13,045 -6.78 2.5368
2024-05-07 2024-03-31 13F MERCK COM 58933Y105 106,054 -351 -0.33 13,994 20.63 2.7482
2024-01-31 2023-12-31 13F MERCK AND CO INC SHS COM 58933Y105 106,405 -1,423 -1.32 11,600 4.50 2.4335
2023-10-30 2023-09-30 13F/A-1 MERCK AND CO INC SHS COM 58933Y105 107,828 -513 -0.47 11,101 -11.21 2.4766
2023-10-30 2023-09-30 13F MERCK AND CO INC SHS COM 58933Y105 107,828 -513 11,101 2.4766
2023-07-28 2023-06-30 13F MERCK AND CO INC SHS COM 58933Y105 108,341 -3,345 -3.00 12,501 5.21 2.6970
2023-04-19 2023-03-31 13F MERCK AND CO INC SHS COM 58933Y105 111,686 -16,456 -12.84 11,882 -16.42 2.5698
2023-01-26 2022-12-31 13F MERCK AND CO INC SHS COM 58933Y105 128,142 606 0.48 14,217 29.45 3.1278
2022-10-21 2022-09-30 13F MERCK AND CO INC SHS COM 58933Y105 127,536 -43,026 -25.23 10,983 -29.37 2.6512
2022-07-20 2022-06-30 13F MERCK AND CO INC SHS COM 58933Y105 170,562 -104 -0.06 15,550 11.05 2.9047
2022-04-25 2022-03-31 13F MERCK AND CO INC SHS COM 58933Y105 170,666 -2,086 -1.21 14,003 5.77 2.2634
2022-01-28 2021-12-31 13F MERCK AND CO INC SHS COM 58933Y105 172,752 1,946 1.14 13,239 3.20 2.0327
2021-10-21 2021-09-30 13F MERCK AND CO INC SHS COM 58933Y105 170,806 -663 -0.39 12,829 -3.79 2.1716
2021-07-29 2021-06-30 13F MERCK AND CO INC SHS COM 58933Y105 171,469 -4,501 -2.56 13,335 -1.70 2.1901
2021-04-22 2021-03-31 13F MERCK AND CO INC SHS COM 58933Y105 175,970 3,786 2.20 13,565 -3.69 2.3175
2021-02-01 2020-12-31 13F MERCK AND CO INC SHS COM 58933Y105 172,184 860 0.50 14,084 -0.89 2.5971
2020-10-23 2020-09-30 13F MERCK AND CO INC SHS COM 58933Y105 171,324 -3,740 -2.14 14,211 4.98 2.9359
2020-07-27 2020-06-30 13F MERCK AND CO INC SHS COM 58933Y105 175,064 1,388 0.80 13,537 1.31 2.9813
2020-04-23 2020-03-31 13F MERCK AND CO INC SHS COM 58933Y105 173,676 2,673 1.56 13,362 -14.08 3.4257
2020-01-24 2019-12-31 13F MERCK AND CO INC SHS COM 58933Y105 171,003 -1,691 -0.98 15,552 6.98 3.0606
2019-10-25 2019-09-30 13F MERCK AND CO INC SHS COM 58933Y105 172,694 -1,207 -0.69 14,537 -0.30 3.0677
2019-07-26 2019-06-30 13F MERCK & CO INC COM COM 58933Y105 173,901 -99 -0.06 14,581 0.76 3.0832
2019-04-29 2019-03-31 13F MERCK & CO INC COM COM 58933Y105 174,000 -1,353 -0.77 14,471 8.01 3.0820
2019-01-28 2018-12-31 13F MERCK & CO INC COM COM 58933Y105 175,353 -695 -0.39 13,398 7.29 3.2868
2018-10-26 2018-09-30 13F MERCK & CO INC COM COM 58933Y105 176,048 -11,002 -5.88 12,488 10.00 2.6566
2018-08-06 2018-06-30 13F MERCK & CO INC COM COM 58933Y105 187,050 -2,720 -1.43 11,353 9.84 2.4346
2018-04-23 2018-03-31 13F MERCK & CO INC COM COM 58933Y105 189,770 2,692 1.44 10,336 -1.81 2.0394
2018-01-26 2017-12-31 13F MERCK & CO INC NEW COM COM 58933Y105 187,078 3,063 1.66 10,527 -10.65 2.0278
2017-10-20 2017-09-30 13F MERCK & CO INC NEW COM COM 58933Y105 184,015 6,597 3.72 11,782 3.61 2.3568
2017-07-28 2017-06-30 13F MERCK & CO INC NEW COM COM 58933Y105 177,418 1,150 0.65 11,371 1.53 2.3077
2017-04-28 2017-03-31 13F MERCK & CO INC NEW COM COM 58933Y105 176,268 -987 -0.56 11,200 7.33 2.2070
2017-01-31 2016-12-31 13F MERCK & CO INC NEW COM COM 58933Y105 177,255 -2,429 -1.35 10,435 -6.95 2.1171
2016-10-21 2016-09-30 13F MERCK & CO INC NEW COM COM 58933Y105 179,684 -8,368 -4.45 11,214 3.51 2.2609
2016-07-26 2016-06-30 13F MERCK & CO INC NEW COM COM 58933Y105 188,052 -6,666 -3.42 10,834 5.15 2.1937
2016-04-13 2016-03-31 13F MERCK & CO INC NEW COM COM 58933Y105 194,718 169 0.09 10,303 0.26 2.5651
2016-01-19 2015-12-31 13F MERCK & CO INC NEW COM COM 58933Y105 194,549 -3,724 -1.88 10,276 4.93 2.5286
2015-10-22 2015-09-30 13F MERCK AND CO INC SHS COM 58933Y105 198,273 -8,005 -3.88 9,793 -16.61 2.1517
2015-07-23 2015-06-30 13F MERCK AND CO INC SHS COM 58933Y105 206,278 -18,518 -8.24 11,743 -9.12 2.3723
2015-04-22 2015-03-31 13F MERCK AND CO INC SHS COM 58933Y105 224,796 224,796 0.00 12,921 2.3683
2015-02-02 2014-12-31 13F MERCK AND CO INC SHS COM 58933Y105 0 -156,004 -100.00 0 -100.00
2014-11-07 2014-09-30 13F MERCK AND CO INC SHS COM 58933Y105 156,004 -1,699 -1.08 9,248 1.37 1.7370
2014-07-16 2014-06-30 13F MERCK AND CO INC SHS COM 58933Y105 157,703 478 0.30 9,123 2.21 1.8486
2014-04-22 2014-03-31 13F MERCK AND CO INC SHS COM 58933Y105 157,225 1,273 0.82 8,926 14.36 1.8656
2014-01-30 2013-12-31 13F MERCK AND CO INC SHS COM 58933Y105 155,952 713 0.46 7,805 5.60 1.6716
2013-10-30 2013-09-30 13F MERCK AND CO INC SHS COM 58933Y105 155,239 -398 -0.26 7,391 2.24 1.7419
2013-07-18 2013-06-30 13F MERCK AND CO INC SHS COM 58933Y105 155,637 155,637 7,229 1.7360
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.