Merck & Co., Inc.
MX ˙ BMV ˙ US58933Y1055
SecurityMX:MRK / Merck & Co., Inc.
InstitutionBoston Research & Management Inc
Latest Disclosed Ownership66,572 shares
Latest Disclosed Value $ 8,007
Boston Research & Management Inc reports 0.88% increase in ownership of MRK / Merck & Co., Inc.

On April 10, 2026 - Boston Research & Management Inc filed a 13F-HR form disclosing ownership of 66,572 shares of Merck & Co., Inc. (MX:MRK) valued at $8,007 USD as of March 31, 2026. The entity filed a previous 13F-HR on February 11, 2026 disclosing 65,994 shares of Merck & Co., Inc.. This represents a change in shares of 0.88% 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)
2026-04-10 2026-03-31 13F Merck COM 58933Y105 66,572 578 0.88 8 33.33 1.9020
2026-02-11 2025-12-31 13F Merck COM 58933Y105 65,994 -1,621 -2.40 7 20.00 1.6016
2025-11-12 2025-09-30 13F Merck COM 58933Y105 67,615 256 0.38 6 0.00 1.2515
2025-08-12 2025-06-30 13F Merck COM 58933Y105 67,359 4,473 7.11 5 0.00 1.2745
2025-05-12 2025-03-31 13F Merck COM 58933Y105 62,886 -1,190 -1.86 6 -16.67 1.4016
2025-02-12 2024-12-31 13F Merck COM 58933Y105 64,076 1,746 2.80 6 -14.29 1.5647
2024-11-12 2024-09-30 13F Merck COM 58933Y105 62,330 1,566 2.58 7 0.00 1.6628
2024-08-13 2024-06-30 13F Merck COM 58933Y105 60,764 -761 -1.24 8 -12.50 1.9021
2024-05-14 2024-03-31 13F Merck COM 58933Y105 61,525 0 0.00 8 33.33 2.0065
2024-02-12 2023-12-31 13F Merck COM 58933Y105 61,525 1,415 2.35 7 0.00 1.7806
2023-11-13 2023-09-30 13F Merck COM 58933Y105 60,110 -272 -0.45 6 0.00 1.8290
2023-08-01 2023-06-30 13F Merck COM 58933Y105 60,382 -1 -0.00 7 0.00 1.9727
2023-05-10 2023-03-31 13F Merck COM 58933Y105 60,383 -911 -1.49 6 0.00 1.9186
2023-02-13 2022-12-31 13F Merck COM 58933Y105 61,294 -1,220 -1.95 7 -99.89 2.1041
2022-11-14 2022-09-30 13F Merck COM 58933Y105 62,514 120 0.19 5,383 -5.36 1.8339
2022-08-11 2022-06-30 13F Merck COM 58933Y105 62,394 -170 -0.27 5,688 10.81 1.8424
2022-05-12 2022-03-31 13F Merck COM 58933Y105 62,564 -510 -0.81 5,133 6.21 1.4901
2022-02-10 2021-12-31 13F Merck COM 58933Y105 63,074 105 0.17 4,833 2.20 1.3196
2021-11-10 2021-09-30 13F/A-1 Merck COM 58933Y105 62,969 3,015 5.03 4,729 1.44 1.4083
2021-11-10 2021-09-30 13F Merck COM 58933Y105 56,604 -3,350 4,363 1.4044
2021-08-11 2021-06-30 13F Merck COM 58933Y105 59,954 3,350 5.92 4,662 6.85 1.4141
2021-05-11 2021-03-31 13F Merck COM 58933Y105 56,604 5,210 10.14 4,363 3.78 1.4044
2021-02-09 2020-12-31 13F Merck COM 58933Y105 51,394 2,716 5.58 4,204 4.14 1.4625
2020-11-09 2020-09-30 13F Merck COM 58933Y105 48,678 -1,145 -2.30 4,037 4.80 1.5787
2020-08-10 2020-06-30 13F Merck COM 58933Y105 49,823 1,292 2.66 3,852 3.19 1.6004
2020-05-08 2020-03-31 13F Merck COM 58933Y105 48,531 192 0.40 3,733 -15.08 1.8742
2020-02-07 2019-12-31 13F Merck COM 58933Y105 48,339 -5 -0.01 4,396 8.04 1.6490
2019-11-12 2019-09-30 13F Merck COM 58933Y105 48,344 820 1.73 4,069 2.13 1.6090
2019-08-07 2019-06-30 13F Merck COM 58933Y105 47,524 880 1.89 3,984 2.71 1.6114
2019-05-07 2019-03-31 13F Merck COM 58933Y105 46,644 -1,205 -2.52 3,879 6.10 1.6162
2019-02-06 2018-12-31 13F Merck COM 58933Y105 47,849 4,520 10.43 3,656 18.97 1.7408
2018-11-13 2018-09-30 13F Merck COM 58933Y105 43,329 140 0.32 3,073 17.25 1.4042
2018-07-30 2018-06-30 13F Merck COM 58933Y105 43,189 641 1.51 2,621 13.12 1.2898
2018-05-09 2018-03-31 13F Merck COM 58933Y105 42,548 37,455 735.42 2,317 710.14 1.1806
2018-02-09 2017-12-31 13F Merck COM 58933Y105 5,093 -2,330 -31.39 286 -39.79 0.1434
2017-11-09 2017-09-30 13F Merck COM 58933Y105 7,423 180 2.49 475 2.37 0.2427
2017-08-08 2017-06-30 13F Merck COM 58933Y105 7,243 0 0.00 464 0.87 0.2510
2017-05-05 2017-03-31 13F Merck COM 58933Y105 7,243 0 0.00 460 7.98 0.2506
2017-02-09 2016-12-31 13F Merck COM 58933Y105 7,243 0 0.00 426 -5.75 0.2424
2016-11-07 2016-09-30 13F Merck COM 58933Y105 7,243 0 0.00 452 8.39 0.2611
2016-08-10 2016-06-30 13F Merck COM 58933Y105 7,243 0 0.00 417 8.88 0.2528
2016-05-13 2016-03-31 13F Merck COM 58933Y105 7,243 0 0.00 383 0.26 0.2385
2016-02-11 2015-12-31 13F Merck COM 58933Y105 7,243 -1,512 -17.27 382 -11.57 0.2375
2015-11-09 2015-09-30 13F Merck COM 58933Y105 8,755 1,000 12.89 432 -2.04 0.2844
2015-07-31 2015-06-30 13F Merck COM 58933Y105 7,755 -100 -1.27 441 -2.22 0.2791
2015-05-11 2015-03-31 13F Merck COM 58933Y105 7,855 0 0.00 451 1.12 0.2860
2015-02-11 2014-12-31 13F Merck COM 58933Y105 7,855 0 0.00 446 -4.09 0.2795
2014-11-04 2014-09-30 13F Merck COM 58933Y105 7,855 0 0.00 465 2.42 0.3127
2014-08-12 2014-06-30 13F Merck COM 58933Y105 7,855 0 0.00 454 2.02 0.3138
2014-05-13 2014-03-31 13F Merck COM 58933Y105 7,855 512 6.97 445 21.25 0.3271
2014-02-07 2013-12-31 13F Merck COM 58933Y105 7,343 0 0.00 367 5.16 0.2821
2013-11-08 2013-09-30 13F Merck COM 58933Y105 7,343 0 0.00 349 2.35 0.2948
2013-08-13 2013-06-30 13F/A-1 Merck COM 58933Y105 7,343 7,343 341 0.3032
2013-08-12 2013-06-30 13F Merck COM 58933Y105 7,343 341 0.3086
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.