Merck & Co., Inc.
BG ˙ BUL ˙ US58933Y1055
SecurityBG:6MK / Merck & Co., Inc.
InstitutionPrudential Financial Inc
Latest Disclosed Ownership1,962,332 shares
Latest Disclosed Value $ 236,048,916
Prudential Financial Inc reports 7.27% decrease in ownership of 6MK / Merck & Co., Inc.

On May 13, 2026 - Prudential Financial Inc filed a 13F-HR form disclosing ownership of 1,962,332 shares of Merck & Co., Inc. (BG:6MK) valued at $236,048,916 USD as of March 31, 2026. The entity filed a previous 13F-HR on February 13, 2026 disclosing 2,116,141 shares of Merck & Co., Inc.. This represents a change in shares of -7.27% 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)
2026-05-13 2026-03-31 13F MERCK COM 58933Y105 1,962,332 -153,809 -7.27 236,049 5.97 0.1634
2026-02-13 2025-12-31 13F MERCK COM 58933Y105 2,116,141 -1,463,904 -40.89 222,745 -25.87 0.2690
2025-11-13 2025-09-30 13F MERCK COM 58933Y105 3,580,045 -249,296 -6.51 300,473 -0.88 0.3571
2025-08-12 2025-06-30 13F MERCK COM 58933Y105 3,829,341 477,923 14.26 303,131 0.77 0.3916
2025-05-13 2025-03-31 13F MERCK COM 58933Y105 3,351,418 706,099 26.69 300,823 14.31 0.4286
2025-02-11 2024-12-31 13F MERCK COM 58933Y105 2,645,319 -751,138 -22.12 263,156 -31.77 0.3607
2024-11-14 2024-09-30 13F MERCK COM 58933Y105 3,396,457 -281,224 -7.65 385,702 -15.29 0.5434
2024-08-13 2024-06-30 13F MERCK COM 58933Y105 3,677,681 -419,924 -10.25 455,297 -15.79 0.6836
2024-05-14 2024-03-31 13F MERCK COM 58933Y105 4,097,605 337,958 8.99 540,679 32.88 0.7613
2024-02-13 2023-12-31 13F MERCK COM 58933Y105 3,759,647 472,696 14.38 406,885 20.14 0.6147
2023-11-13 2023-09-30 13F MERCK COM 58933Y105 3,286,951 -977,744 -22.93 338,675 -31.18 0.5314
2023-08-11 2023-06-30 13F MERCK COM 58933Y105 4,264,695 -327,041 -7.12 492,103 0.73 0.7166
2023-05-12 2023-03-31 13F MERCK COM 58933Y105 4,591,736 124,871 2.80 488,515 -1.43 0.7649
2023-02-14 2022-12-31 13F MERCK COM 58933Y105 4,466,865 48,400 1.10 495,599 30.23 0.8352
2022-11-04 2022-09-30 13F MERCK COM 58933Y105 4,418,465 -420,148 -8.68 380,549 -13.75 0.6451
2022-08-15 2022-06-30 13F MERCK COM 58933Y105 4,838,613 89,068 1.88 441,215 13.22 0.6999
2022-05-13 2022-03-31 13F MERCK COM 58933Y105 4,749,545 101,530 2.18 389,701 9.22 0.5179
2022-02-14 2021-12-31 13F MERCK COM 58933Y105 4,648,015 2,202,124 90.03 356,801 94.37 0.4433
2021-11-15 2021-09-30 13F MERCK COM 58933Y105 2,445,891 -57,774 -2.31 183,568 -5.72 0.2562
2021-08-16 2021-06-30 13F MERCK COM 58933Y105 2,503,665 -2,322,293 -48.12 194,709 -47.66 0.2679
2021-05-12 2021-03-31 13F MERCK & CO. COM 58933Y105 4,825,958 -111,900 -2.27 372,033 -7.89 0.5573
2021-08-16 2020-12-31 13F/A-1 MERCK & CO. COM 0081 58933Y105 4,937,858 4,916,782 23,328.82 403,920 23,007.55 0.6790
2021-02-16 2020-12-31 13F MERCK & CO. COM 58933Y105 4,937,858 4,916,782 403,917 0.6790
2021-08-05 2020-09-30 13F/A-1 MERCK & CO. COM 58933Y105 21,076 5,818 38.13 1,748 48.14 0.2526
2020-11-16 2020-09-30 13F MERCK & CO. COM 58933Y105 4,767,520 4,752,262 395,467 0.7460
2021-08-05 2020-06-30 13F/A-1 MERCK & CO. COM 0077 58933Y105 15,258 8,411 122.84 1,180 123.91 0.2185
2020-08-12 2020-06-30 13F MERCK & CO. COM 58933Y105 4,914,952 4,908,105 380,074 0.7319
2021-08-05 2020-03-31 13F/A-1 MERCK & CO. COM 0076 58933Y105 6,847 2,268 49.53 527 26.68 0.1369
2020-05-12 2020-03-31 13F MERCK & CO. COM 58933Y105 5,316,294 5,311,715 409,036 0.9061
2021-08-05 2019-12-31 13F/A-1 MERCK COM 0090 58933Y105 4,579 916 25.01 416 35.06 0.1084
2020-02-11 2019-12-31 13F MERCK COM 58933Y105 5,991,246 5,987,583 544,904 0.8073
2021-08-05 2019-09-30 13F/A-1 MERCK COM 0084 58933Y105 3,663 -637 -14.81 308 -14.68 0.1005
2019-11-13 2019-09-30 13F MERCK COM 58933Y105 5,907,975 5,903,675 497,333 0.7889
2021-08-05 2019-06-30 13F/A-1 MERCK COM 58933Y105 4,300 2,542 144.60 361 147.26 0.1254
2019-08-08 2019-06-30 13F MERCK COM 58933Y105 6,367,559 6,365,801 533,920 0.8319
2021-08-05 2019-03-31 13F/A-1 MERCK COM 58933Y105 1,758 929 112.06 146 131.75 0.0620
2019-05-15 2019-03-31 13F MERCK COM 58933Y105 5,854,055 5,853,226 486,882 0.8108
2021-08-05 2018-12-31 13F/A-1 MERCK COM 58933Y105 829 505 155.86 63 173.91 0.0510
2019-02-07 2018-12-31 13F MERCK COM 58933Y105 6,103,959 815,645 466,403 0.8192
2021-09-01 2018-09-30 13F/A-1 MERCK COM 0070 58933Y105 324 91 39.06 23 64.29 0.0370
2018-11-07 2018-09-30 13F MERCK COM 58933Y105 5,288,314 5,288,081 375,153 0.5526
2021-09-01 2018-06-30 13F/A-1 MERCK COM 58933Y105 233 -71 -23.36 14 -17.65 0.0502
2018-08-13 2018-06-30 13F MERCK COM 58933Y105 5,308,264 5,307,960 322,212 0.4816
2021-09-01 2018-03-31 13F/A-1 MERCK COM 58933Y105 304 -5,281,648 -99.99 17 -99.99 0.2216
2018-05-04 2018-03-31 13F MERCK COM 58933Y105 4,682,234 -599,718 255,041 0.3885
2018-02-13 2017-12-31 13F MERCK COM 58933Y105 5,281,952 29,954 0.57 297,215 -11.62 0.4048
2017-11-02 2017-09-30 13F MERCK COM 58933Y105 5,251,998 -169,240 -3.12 336,285 -3.21 0.5561
2017-08-07 2017-06-30 13F MERCK COM 58933Y105 5,421,238 -29,207 -0.54 347,447 0.32 0.5169
2017-05-10 2017-03-31 13F MERCK COM 58933Y105 5,450,445 647,140 13.47 346,322 22.47 0.5400
2017-02-07 2016-12-31 13F MERCK COM 58933Y105 4,803,305 -37,800 -0.78 282,770 -6.41 0.4547
2016-11-04 2016-09-30 13F MERCK COM 58933Y105 4,841,105 -1,276,110 -20.86 302,133 -14.27 0.4990
2016-08-09 2016-06-30 13F MERCK COM 58933Y105 6,117,215 406,560 7.12 352,413 16.63 0.5928
2016-05-09 2016-03-31 13F MERCK & CO INC COM 58933Y105 5,710,655 -1,714,040 -23.09 302,151 -22.95 0.5404
2016-02-12 2015-12-31 13F MERCK & CO INC COM 58933Y105 7,424,695 213,000 2.95 392,172 10.10 0.7100
2015-11-10 2015-09-30 13F MERCK & CO INC COM 58933Y105 7,211,695 736,920 11.38 356,185 -3.37 0.7026
2015-08-06 2015-06-30 13F MERCK & CO INC COM 58933Y105 6,474,775 24,090 0.37 368,609 -0.59 0.6544
2015-05-01 2015-03-31 13F MERCK & CO INC COM 58933Y105 6,450,685 18,750 0.29 370,785 1.51 0.6426
2015-02-06 2014-12-31 13F MERCK & CO INC COM 58933Y105 6,431,935 648,730 11.22 365,269 6.55 0.6623
2014-11-12 2014-09-30 13F MERCK & CO INC COM 58933Y105 5,783,205 -279,099 -4.60 342,828 -2.25 0.6452
2014-08-13 2014-06-30 13F MERCK & CO INC COM 58933Y105 6,062,304 -315,010 -4.94 350,704 -3.13 0.6186
2014-05-14 2014-03-31 13F MERCK & CO INC COM 58933Y105 6,377,314 -452,397 -6.62 362,040 5.91 0.6739
2014-02-11 2013-12-31 13F MERCK & CO INC COM 58933Y105 6,829,711 555,418 8.85 341,828 14.43 0.6785
2013-11-07 2013-09-30 13F MERCK & CO INC COM 58933Y105 6,274,293 -245,286 -3.76 298,719 -1.36 0.6350
2013-08-07 2013-06-30 13F MERCK & CO INC COM 58933Y105 6,519,579 6,519,579 302,835 0.6711
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.