Merck & Co., Inc.
DE ˙ XTRA ˙ US58933Y1055
102,78 € ↑2,84 (2,84%)
2026-06-04
DEL PRIS
SecurityDE:6MK / Merck & Co., Inc.
InstitutionAppleton Partners Inc/ma
Latest Disclosed Ownership6,368 shares
Latest Disclosed Value $ 766
Appleton Partners Inc/ma reports 12.72% decrease in ownership of 6MK / Merck & Co., Inc.

On April 28, 2026 - Appleton Partners Inc/ma filed a 13F-HR form disclosing ownership of 6,368 shares of Merck & Co., Inc. (DE:6MK) valued at $663,546 USD as of March 31, 2026. The entity filed a previous 13F-HR on January 9, 2026 disclosing 7,296 shares of Merck & Co., Inc.. The current value of the position is $654,503 USD.

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)
2026-04-28 2026-03-31 13F MERCK & CO INC COM CS 58933Y105 6,368 -928 -12.72 1 0.0534
2026-01-09 2025-12-31 13F MERCK & CO INC COM CS 58933Y105 7,296 -216 -2.88 1 0.0506
2025-11-05 2025-09-30 13F MERCK CS 58933Y105 7,512 -357 -4.54 1 0.0423
2025-07-22 2025-06-30 13F MERCK CS 58933Y105 7,869 -525 -6.25 1 0.0441
2025-04-22 2025-03-31 13F MERCK CS 58933Y105 8,394 -98,431 -92.14 1 -100.00 0.0582
2025-01-28 2024-12-31 13F MERCK CS 58933Y105 106,825 -5,287 -4.72 11 -16.67 0.7855
2024-10-01 2024-09-30 13F MERCK CS 58933Y105 112,112 7,248 6.91 13 0.00 0.9366
2024-07-02 2024-06-30 13F MERCK CS 58933Y105 104,864 702 0.67 13 -7.69 0.9999
2024-04-01 2024-03-31 13F MERCK CS 58933Y105 104,162 -552 -0.53 14 18.18 1.0667
2024-01-02 2023-12-31 13F MERCK CS 58933Y105 104,714 6,636 6.77 11 10.00 0.9206
2023-10-03 2023-09-30 13F MERCK CS 58933Y105 98,078 11,153 12.83 10 0.00 0.8974
2023-07-10 2023-06-30 13F MERCK CS 58933Y105 86,925 22,479 34.88 10 66.67 0.8468
2023-04-10 2023-03-31 13F MERCK CS 58933Y105 64,446 8,790 15.79 7 0.00 0.6098
2023-01-19 2022-12-31 13F MERCK CS 58933Y105 55,656 9,818 21.42 6 -99.85 0.5850
2022-10-27 2022-09-30 13F MERCK CS 58933Y105 45,838 8,122 21.53 3,948 14.80 0.3949
2022-07-08 2022-06-30 13F MERCK CS 58933Y105 37,716 1,565 4.33 3,439 15.95 0.3252
2022-04-05 2022-03-31 13F MERCK CS 58933Y105 36,151 -5,200 -12.58 2,966 -6.41 0.2425
2022-02-03 2021-12-31 13F MERCK CS 58933Y105 41,351 2,029 5.16 3,169 7.31 0.2385
2021-10-14 2021-09-30 13F MERCK CS 58933Y105 39,322 -708 -1.77 2,953 -5.14 0.2459
2021-07-07 2021-06-30 13F MERCK CS 58933Y105 40,030 -191 -0.47 3,113 0.39 0.2651
2021-04-19 2021-03-31 13F MERCK & CO. INC COM CS 58933Y105 40,221 -1,255 -3.03 3,101 -8.61 0.2883
2021-01-19 2020-12-31 13F MERCK & CO. INC COM CS 58933Y105 41,476 -446 -1.06 3,393 -2.42 0.3341
2020-10-14 2020-09-30 13F MERCK & CO. INC COM COM 58933Y105 41,922 -548 -1.29 3,477 5.88 0.3839
2020-08-14 2020-06-30 13F MERCK & CO. INC COM COM 58933Y105 42,470 -251 -0.59 3,284 -0.09 0.3932
2020-05-04 2020-03-31 13F MERCK & CO. INC COM COM 58933Y105 42,721 -348 -0.81 3,287 -16.08 0.4555
2020-01-13 2019-12-31 13F MERCK & CO INC COM COM 58933Y105 43,069 -1,493 -3.35 3,917 4.43 0.4303
2019-11-04 2019-09-30 13F MERCK & CO INC COM COM 58933Y105 44,562 120 0.27 3,751 0.67 0.4528
2019-07-25 2019-06-30 13F MERCK & CO INC COM COM 58933Y105 44,442 -533 -1.19 3,726 -0.40 0.4605
2019-04-17 2019-03-31 13F MERCK & CO INC COM COM 58933Y105 44,975 1,891 4.39 3,741 13.64 0.4959
2019-01-17 2018-12-31 13F MERCK & CO INC COM COM 58933Y105 43,084 -453 -1.04 3,292 6.57 0.4929
2018-10-09 2018-09-30 13F MERCK & CO INC COM COM 58933Y105 43,537 2,055 4.95 3,089 22.68 0.4113
2018-08-08 2018-06-30 13F MERCK & CO INC COM COM 58933Y105 41,482 4,901 13.40 2,518 26.34 0.3605
2018-04-11 2018-03-31 13F MERCK & CO INC COM COM 58933Y105 36,581 5,123 16.29 1,993 12.60 0.3024
2018-01-12 2017-12-31 13F MERCK & CO INC COM COM 58933Y105 31,458 2,886 10.10 1,770 -3.23 0.2745
2017-10-12 2017-09-30 13F MERCK & CO INC COM COM 58933Y105 28,572 1,761 6.57 1,829 6.46 0.3081
2017-07-11 2017-06-30 13F MERCK & CO INC COM COM 58933Y105 26,811 -10 -0.04 1,718 0.82 0.2888
2017-05-01 2017-03-31 13F MERCK & CO INC COM COM 58933Y105 26,821 -2,134 -7.37 1,704 -0.06 0.3135
2017-02-13 2016-12-31 13F MERCK & CO INC COM COM 58933Y105 28,955 -208 -0.71 1,705 -6.32 0.3446
2016-11-03 2016-09-30 13F MERCK & CO INC COM COM 58933Y105 29,163 -2,251 -7.17 1,820 0.55 0.3429
2016-08-03 2016-06-30 13F MERCK & CO INC COM COM 58933Y105 31,414 -230 -0.73 1,810 8.12 0.3699
2016-04-21 2016-03-31 13F MERCK & CO INC NEW COM COM 58933Y105 31,644 -10 -0.03 1,674 0.12 0.3308
2016-01-22 2015-12-31 13F MERCK & CO INC NEW COM COM 58933Y105 31,654 2,757 9.54 1,672 17.17 0.3298
2015-10-15 2015-09-30 13F MERCK & CO INC NEW COM COM 58933Y105 28,897 7,316 33.90 1,427 16.11 0.3244
2015-07-15 2015-06-30 13F MERCK & CO INC NEW COM COM 58933Y105 21,581 310 1.46 1,229 0.49 0.2753
2015-04-30 2015-03-31 13F MERCK & CO INC NEW COM COM 58933Y105 21,271 21,271 0.00 1,223 0.2758
2015-02-04 2014-12-31 13F MERCK & CO INC NEW COM COM 58933Y105 0 -22,551 -100.00 0 -100.00
2014-11-06 2014-09-30 13F MERCK & CO INC NEW COM COM 58933Y105 22,551 2,201 10.82 1,337 13.59 0.3122
2014-07-23 2014-06-30 13F MERCK & CO INC NEW COM COM 58933Y105 20,350 -100 -0.49 1,177 1.38 0.2752
2014-04-30 2014-03-31 13F MERCK & CO INC NEW COM COM 58933Y105 20,450 2,325 12.83 1,161 28.00 0.2747
2014-02-13 2013-12-31 13F MERCK & CO INC NEW COM COMMON STOCK 58933Y105 18,125 1,633 9.90 907 15.54 0.2175
2013-10-22 2013-09-30 13F MERCK & CO INC NEW COM COMMON STOCK 58933Y105 16,492 799 5.09 785 -99.89 0.2104
2013-08-13 2013-06-30 13F MERCK & CO INC NEW COM COMMON STOCK 58933Y105 15,693 15,693 728,940 0.2102
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.