Merck & Co., Inc.
MX ˙ BMV ˙ US58933Y1055
SecurityMX:MRK / Merck & Co., Inc.
InstitutionBridgeway Capital Management Inc
Latest Disclosed Ownership225,105 shares
Latest Disclosed Value $ 27,077,870
Bridgeway Capital Management Inc reports 15.07% decrease in ownership of MRK / Merck & Co., Inc.

On May 15, 2026 - Bridgeway Capital Management Inc filed a 13F-HR form disclosing ownership of 225,105 shares of Merck & Co., Inc. (MX:MRK) valued at $27,077,870 USD as of March 31, 2026. The entity filed a previous 13F-HR on February 17, 2026 disclosing 265,061 shares of Merck & Co., Inc.. This represents a change in shares of -15.07% 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)
2026-05-15 2026-03-31 13F MERCK COM 58933Y105 225,105 -39,956 -15.07 27,078 -2.95 0.5446
2026-02-17 2025-12-31 13F MERCK COM 58933Y105 265,061 -43,895 -14.21 27,900 7.60 0.5848
2025-11-14 2025-09-30 13F MERCK COM 58933Y105 308,956 16,772 5.74 25,931 12.11 0.5531
2025-08-14 2025-06-30 13F MERCK COM 58933Y105 292,184 45,671 18.53 23,129 4.53 0.5489
2025-05-15 2025-03-31 13F MERCK COM 58933Y105 246,513 31,401 14.60 22,127 3.40 0.5572
2025-02-14 2024-12-31 13F MERCK COM 58933Y105 215,112 29,549 15.92 21,399 1.55 0.4787
2024-11-14 2024-09-30 13F MERCK COM 58933Y105 185,563 24,611 15.29 21,072 5.76 0.4555
2024-08-14 2024-06-30 13F MERCK COM 58933Y105 160,952 13,021 8.80 19,926 2.08 0.4664
2024-05-15 2024-03-31 13F MERCK COM 58933Y105 147,931 -5,062 -3.31 19,519 17.03 0.3988
2024-02-14 2023-12-31 13F MERCK COM 58933Y105 152,993 34,562 29.18 16,679 36.80 0.3578
2023-11-14 2023-09-30 13F MERCK COM 58933Y105 118,431 8,610 7.84 12,192 -3.79 0.2956
2023-08-14 2023-06-30 13F MERCK COM 58933Y105 109,821 81,786 291.73 12,672 324.95 0.3032
2023-05-15 2023-03-31 13F MERCK COM 58933Y105 28,035 -1,750 -5.88 2,983 -9.75 0.0792
2023-02-14 2022-12-31 13F MERCK COM 58933Y105 29,785 -28,600 -48.99 3,305 -34.29 0.0855
2022-11-14 2022-09-30 13F MERCK COM 58933Y105 58,385 -30,700 -34.46 5,028 -38.09 0.1346
2022-08-15 2022-06-30 13F MERCK COM 58933Y105 89,085 -34,500 -27.92 8,122 -19.90 0.1856
2022-05-16 2022-03-31 13F MERCK COM 58933Y105 123,585 -10,850 -8.07 10,140 -1.58 0.1960
2022-02-14 2021-12-31 13F MERCK COM 58933Y105 134,435 -205,400 -60.44 10,303 -59.64 0.1914
2021-11-15 2021-09-30 13F MERCK COM 58933Y105 339,835 -38,500 -10.18 25,525 -13.25 0.4876
2021-08-16 2021-06-30 13F MERCK COM 58933Y105 378,335 600 0.16 29,423 1.04 0.5262
2021-05-17 2021-03-31 13F MERCK & CO. COM 58933Y105 377,735 33,600 9.76 29,120 3.45 0.5443
2021-02-16 2020-12-31 13F MERCK & CO. COM 58933Y105 344,135 -22,200 -6.06 28,150 -7.36 0.5950
2020-11-16 2020-09-30 13F MERCK & CO. COM 58933Y105 366,335 220,100 150.51 30,387 168.72 0.6969
2020-08-31 2020-06-30 13F/A-1 MERCK & CO. COM 58933Y105 146,235 6,700 4.80 11,308 5.33 0.2286
2020-08-14 2020-06-30 13F MERCK & CO. COM 58933Y105 146,235 6,700 11,308 231,261.2059
2020-05-15 2020-03-31 13F MERCK & CO. COM 58933Y105 139,535 -779,000 -84.81 10,736 -87.15 0.2458
2020-02-14 2019-12-31 13F MERCK COM 58933Y105 918,535 -244,600 -21.03 83,541 -14.68 1.1235
2019-11-14 2019-09-30 13F MERCK COM 58933Y105 1,163,135 -40,800 -3.39 97,913 -3.01 1.3536
2019-08-14 2019-06-30 13F MERCK COM 58933Y105 1,203,935 -9,450 -0.78 100,950 0.03 1.2906
2019-05-15 2019-03-31 13F MERCK COM 58933Y105 1,213,385 44,200 3.78 100,917 12.96 1.2568
2019-02-14 2018-12-31 13F MERCK COM 58933Y105 1,169,185 910,650 352.23 89,337 387.12 1.1872
2018-11-13 2018-09-30 13F MERCK COM 58933Y105 258,535 23,200 9.86 18,340 28.39 0.1785
2018-08-14 2018-06-30 13F MERCK COM 58933Y105 235,335 -13,240 -5.33 14,285 5.50 0.1450
2018-05-15 2018-03-31 13F MERCK COM 58933Y105 248,575 -5,000 -1.97 13,540 -5.11 0.1454
2018-02-14 2017-12-31 13F MERCK COM 58933Y105 253,575 32,370 14.63 14,269 0.74 0.1537
2017-11-14 2017-09-30 13F MERCK COM 58933Y105 221,205 12,070 5.77 14,164 5.68 0.1616
2017-08-14 2017-06-30 13F MERCK COM 58933Y105 209,135 -11,600 -5.26 13,403 -4.44 0.1614
2017-05-15 2017-03-31 13F MERCK COM 58933Y105 220,735 -30,830 -12.26 14,026 -5.29 0.1698
2017-02-14 2016-12-31 13F MERCK COM 58933Y105 251,565 23,030 10.08 14,810 3.84 0.1932
2016-11-14 2016-09-30 13F MERCK COM 58933Y105 228,535 -35,800 -13.54 14,263 -6.34 0.2125
2016-08-15 2016-06-30 13F MERCK COM 58933Y105 264,335 -71,820 -21.37 15,228 -14.38 0.2361
2016-05-16 2016-03-31 13F MERCK & CO INC COM 58933Y105 336,155 10,640 3.27 17,786 3.44 0.2992
2016-02-16 2015-12-31 13F MERCK & CO INC COM 58933Y105 325,515 -5,610 -1.69 17,194 5.14 0.3197
2015-11-16 2015-09-30 13F MERCK & CO INC COM 58933Y105 331,125 15,730 4.99 16,354 -8.92 0.3420
2015-10-14 2015-06-30 13F/A-1 MERCK & CO INC COM 58933Y105 315,395 -30,010 -8.69 17,955 -9.56 0.3538
2015-08-14 2015-06-30 13F MERCK & CO INC COM 58933Y105 315,395 17,955
2015-05-15 2015-03-31 13F MERCK & CO INC COM 58933Y105 345,405 -106,140 -23.51 19,854 -22.58 0.4101
2015-03-10 2014-12-31 13F/A-1 MERCK & CO INC COM 58933Y105 451,545 29,720 7.05 25,643 2.55 0.5837
2015-02-17 2014-12-31 13F MERCK & CO INC COM 58933Y105 451,545 25,643
2014-11-14 2014-09-30 13F MERCK & CO INC COM 58933Y105 421,825 5,500 1.32 25,006 3.83 0.6307
2014-08-14 2014-06-30 13F MERCK & CO INC COM 58933Y105 416,325 -11,320 -2.65 24,084 -0.79 0.6317
2014-05-15 2014-03-31 13F MERCK & CO INC COM 58933Y105 427,645 67,050 18.59 24,277 34.51 0.6945
2014-02-14 2013-12-31 13F MERCK & CO INC NEW COM COM 58933Y105 360,595 -2,310 -0.64 18,048 4.46 0.5492
2013-11-14 2013-09-30 13F MERCK & CO INC COM 58933Y105 362,905 9,250 2.62 17,278 5.18 0.5895
2013-08-14 2013-06-30 13F MERCK & CO INC COM 58933Y105 353,655 353,655 16,427 0.6562
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.