Merck & Co., Inc.
MX ˙ BMV ˙ US58933Y1055
SecurityMX:MRK / Merck & Co., Inc.
InstitutionFactory Mutual Insurance Co
Latest Disclosed Ownership281,024 shares
Latest Disclosed Value $ 33,804,377
Factory Mutual Insurance Co reports 1.32% increase in ownership of MRK / Merck & Co., Inc.

On May 5, 2026 - Factory Mutual Insurance Co filed a 13F-HR form disclosing ownership of 281,024 shares of Merck & Co., Inc. (MX:MRK) valued at $33,804,377 USD as of March 31, 2026. The entity filed a previous 13F-HR on January 23, 2026 disclosing 277,374 shares of Merck & Co., Inc.. This represents a change in shares of 1.32% 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)
2026-05-05 2026-03-31 13F MERCK COM 58933Y105 281,024 3,650 1.32 33,804 15.78 0.3803
2026-01-23 2025-12-31 13F MERCK COM 58933Y105 277,374 -3,650 -1.30 29,196 23.79 0.2960
2025-11-10 2025-09-30 13F MERCK COM 58933Y105 281,024 0 0.00 23,586 6.03 0.2297
2025-08-07 2025-06-30 13F MERCK COM 58933Y105 281,024 -206,756 -42.39 22,246 -49.19 0.2432
2025-04-17 2025-03-31 13F MERCK COM 58933Y105 487,780 -71,200 -12.74 43,783 -21.26 0.5079
2025-01-24 2024-12-31 13F MERCK COM 58933Y105 558,980 0 0.00 55,607 -12.40 0.6013
2024-10-10 2024-09-30 13F MERCK COM 58933Y105 558,980 -40,000 -6.68 63,478 -14.40 0.6565
2024-07-23 2024-06-30 13F MERCK COM 58933Y105 598,980 -41,000 -6.41 74,154 -12.19 0.8448
2024-04-12 2024-03-31 13F MERCK COM 58933Y105 639,980 0 0.00 84,445 21.03 0.9700
2024-01-23 2023-12-31 13F MERCK COM 58933Y105 639,980 0 0.00 69,771 5.90 0.8665
2023-11-07 2023-09-30 13F MERCK COM 58933Y105 639,980 0 0.00 65,886 -10.78 0.9190
2023-07-27 2023-06-30 13F MERCK COM 58933Y105 639,980 -123,300 -16.15 73,847 -9.06 1.0893
2023-05-08 2023-03-31 13F MERCK COM 58933Y105 763,280 -46,500 -5.74 81,205 -9.62 1.2691
2023-02-02 2022-12-31 13F MERCK COM 58933Y105 809,780 -139,673 -14.71 89,845 9.88 1.3588
2022-11-04 2022-09-30 13F MERCK COM 58933Y105 949,453 -100,771 -9.60 81,768 -14.60 1.3425
2022-08-08 2022-06-30 13F MERCK COM 58933Y105 1,050,224 -112,600 -9.68 95,749 0.35 1.5697
2022-05-13 2022-03-31 13F MERCK COM 58933Y105 1,162,824 -17,600 -1.49 95,411 4.07 1.2902
2022-02-10 2021-12-31 13F MERCK COM 58933Y105 1,180,424 -185,967 -13.61 91,684 -10.66 1.3237
2021-11-12 2021-09-30 13F MERCK COM 58933Y105 1,366,391 42,600 3.22 102,628 -0.31 1.2818
2021-07-14 2021-06-30 13F MERCK COM 58933Y105 1,323,791 -68,770 -4.94 102,951 -4.10 1.2592
2021-05-10 2021-03-31 13F MERCK & CO. COM 58933Y105 1,392,561 185,725 15.39 107,352 8.75 1.3734
2021-02-17 2020-12-31 13F MERCK & CO. COM 58933Y105 1,206,836 -29,900 -2.42 98,719 -3.77 1.3345
2020-10-19 2020-09-30 13F MERCK & CO. COM 58933Y105 1,236,736 35,800 2.98 102,587 10.46 1.6603
2020-07-13 2020-06-30 13F MERCK & CO. COM 58933Y105 1,200,936 10,800 0.91 92,869 1.42 1.5926
2020-04-16 2020-03-31 13F MERCK & CO. COM 58933Y105 1,190,136 137,800 13.09 91,569 -4.33 1.7389
2020-01-28 2019-12-31 13F MERCK COM 58933Y105 1,052,336 -5,800 -0.55 95,710 7.45 1.4112
2019-10-22 2019-09-30 13F MERCK COM 58933Y105 1,058,136 -78,300 -6.89 89,074 -6.52 1.3771
2019-07-16 2019-06-30 13F MERCK COM 58933Y105 1,136,436 -140,500 -11.00 95,291 -8.43 1.1393
2019-04-09 2019-03-31 13F MERCK COM 58933Y105 1,276,936 430,500 50.86 104,058 60.89 1.2288
2019-01-14 2018-12-31 13F MERCK COM 58933Y105 846,436 114,999 15.72 64,677 24.65 0.8299
2018-10-10 2018-09-30 13F MERCK COM 58933Y105 731,437 -113,300 -13.41 51,888 1.20 0.5386
2018-07-19 2018-06-30 13F MERCK COM 58933Y105 844,737 0 0.00 51,275 11.44 0.5502
2018-04-05 2018-03-31 13F MERCK COM 58933Y105 844,737 0 0.00 46,013 -3.20 0.5039
2018-01-16 2017-12-31 13F MERCK COM 58933Y105 844,737 0 0.00 47,533 -12.12 0.4972
2017-10-11 2017-09-30 13F MERCK COM 58933Y105 844,737 18,767 2.27 54,090 2.18 0.5930
2017-07-10 2017-06-30 13F MERCK COM 58933Y105 825,970 0 0.00 52,937 0.87 0.6123
2017-04-21 2017-03-31 13F MERCK COM 58933Y105 825,970 -9,000 -1.08 52,482 4.44 0.6216
2017-01-19 2016-12-31 13F MERCK COM 58933Y105 834,970 0 0.00 50,249 -3.57 0.5963
2016-10-26 2016-09-30 13F MERCK COM 58933Y105 834,970 -40,000 -4.57 52,110 3.38 0.6444
2016-07-12 2016-06-30 13F MERCK COM 58933Y105 874,970 -109,573 -11.13 50,407 -3.23 0.6641
2016-04-27 2016-03-31 13F MERCK & CO INC COM 58933Y105 984,543 -120,000 -10.86 52,092 -10.71 0.6741
2016-01-14 2015-12-31 13F MERCK & CO INC COM 58933Y105 1,104,543 -22,000 -1.95 58,342 4.86 0.7848
2015-10-14 2015-09-30 13F MERCK & CO INC COM 58933Y105 1,126,543 0 0.00 55,640 -13.24 0.7611
2015-07-21 2015-06-30 13F MERCK & CO INC COM 58933Y105 1,126,543 0 0.00 64,134 -0.95 0.8377
2015-04-13 2015-03-31 13F MERCK & CO INC COM 58933Y105 1,126,543 0 0.00 64,752 1.21 0.8531
2015-01-12 2014-12-31 13F MERCK & CO INC COM 58933Y105 1,126,543 -104,000 -8.45 63,976 -12.30 0.8622
2014-11-04 2014-09-30 13F MERCK & CO INC COM 58933Y105 1,230,543 -6,600 -0.53 72,947 1.93 1.0088
2014-08-12 2014-06-30 13F MERCK & CO INC COM 58933Y105 1,237,143 0 0.00 71,569 1.90 0.9786
2014-05-15 2014-03-31 13F MERCK & CO INC COM 58933Y105 1,237,143 80,000 6.91 70,233 21.27 1.0167
2014-02-04 2013-12-31 13F MERCK & CO INC COM 58933Y105 1,157,143 -40,000 -3.34 57,915 1.61 0.8517
2013-10-16 2013-09-30 13F MERCK & CO INC COM 58933Y105 1,197,143 -30,000 -2.44 56,995 -0.01 0.9039
2013-07-25 2013-06-30 13F MERCK & CO INC COM 58933Y105 1,227,143 1,227,143 57,001 0.9342
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.