Merck & Co., Inc.
MX ˙ BMV ˙ US58933Y1055
SecurityMX:MRK / Merck & Co., Inc.
InstitutionPrincipal Financial Group Inc
Latest Disclosed Ownership4,709,942 shares
Latest Disclosed Value $ 566,559,060
Principal Financial Group Inc reports 7.33% decrease in ownership of MRK / Merck & Co., Inc.

On May 4, 2026 - Principal Financial Group Inc filed a 13F-HR form disclosing ownership of 4,709,942 shares of Merck & Co., Inc. (MX:MRK) valued at $566,559,060 USD as of March 31, 2026. The entity filed a previous 13F-HR on February 2, 2026 disclosing 5,082,718 shares of Merck & Co., Inc.. This represents a change in shares of -7.33% 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.

Upgrade to unlock premium data and export to Excel .

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)
2026-05-04 2026-03-31 13F MERCK COM 58933Y105 4,709,942 -372,776 -7.33 566,559 5.90 0.3026
2026-02-02 2025-12-31 13F MERCK COM 58933Y105 5,082,718 -126,642 -2.43 535,007 22.36 0.2732
2025-11-04 2025-09-30 13F MERCK COM 58933Y105 5,209,360 -420,231 -7.46 437,224 -1.89 0.2205
2025-08-08 2025-06-30 13F MERCK COM 58933Y105 5,629,591 159 0.00 445,639 -11.81 0.2356
2025-04-28 2025-03-31 13F MERCK COM 58933Y105 5,629,432 -873,203 -13.43 505,298 -21.89 0.2835
2025-01-31 2024-12-31 13F MERCK COM 58933Y105 6,502,635 146,685 2.31 646,882 -10.38 0.3526
2024-10-31 2024-09-30 13F MERCK COM 58933Y105 6,355,950 518,270 8.88 721,782 -0.13 0.3976
2024-07-29 2024-06-30 13F MERCK COM 58933Y105 5,837,680 -194,575 -3.23 722,705 -9.20 0.4292
2024-04-29 2024-03-31 13F MERCK COM 58933Y105 6,032,255 120,573 2.04 795,956 23.50 0.4678
2024-02-07 2023-12-31 13F MERCK COM 58933Y105 5,911,682 20,018 0.34 644,492 6.26 0.4109
2023-11-02 2023-09-30 13F MERCK COM 58933Y105 5,891,664 8,122 0.14 606,547 -10.66 0.4358
2023-08-07 2023-06-30 13F MERCK COM 58933Y105 5,883,542 -622,878 -9.57 678,902 -1.92 0.4640
2023-05-09 2023-03-31 13F MERCK COM 58933Y105 6,506,420 -14,530 -0.22 692,218 -4.32 0.4948
2023-02-09 2022-12-31 13F MERCK COM 58933Y105 6,520,950 -234,630 -3.47 723,499 24.36 0.5448
2022-11-09 2022-09-30 13F MERCK COM 58933Y105 6,755,580 -33,308 -0.49 581,791 -6.00 0.4624
2022-08-10 2022-06-30 13F MERCK COM 58933Y105 6,788,888 6,652,190 4,866.34 618,942 5,418.38 0.4579
2022-05-09 2022-03-31 13F MERCK COM 58933Y105 136,698 -6,928,090 -98.07 11,216 -97.93 0.0045
2022-05-09 2022-03-31 13F MERCK COM 58933Y105 7,470,052 612,918
2022-02-09 2021-12-31 13F MERCK COM 58933Y105 7,064,788 -316,454 -4.29 541,411 -2.34 0.3232
2021-11-09 2021-09-30 13F MERCK COM 58933Y105 7,381,242 154,016 2.13 554,405 -1.36 0.3616
2021-08-10 2021-06-30 13F MERCK COM 58933Y105 7,227,226 464,160 6.86 562,061 7.81 0.3632
2021-05-10 2021-03-31 13F MERCK & CO. COM 58933Y105 6,763,066 -376,402 -5.27 521,365 -10.73 0.3679
2021-02-23 2020-12-31 13F/A-1 MERCK & CO. COM 58933Y105 7,139,468 -47,159 -0.66 584,008 -2.03 0.4326
2021-02-08 2020-12-31 13F MERCK & CO. COM 58933Y105 7,139,482 -47,145 584,009 229,758.1408
2020-11-06 2020-09-30 13F MERCK & CO. COM 58933Y105 7,186,627 -202,599 -2.74 596,130 4.33 0.5016
2020-08-05 2020-06-30 13F MERCK & CO. COM 58933Y105 7,389,226 429,690 6.17 571,409 6.71 0.5066
2020-05-12 2020-03-31 13F MERCK & CO. COM 58933Y105 6,959,536 -82,383 -1.17 535,466 -16.39 0.5927
2020-02-05 2019-12-31 13F MERCK COM 58933Y105 7,041,919 -326,374 -4.43 640,463 3.26 0.5337
2019-11-13 2019-09-30 13F MERCK COM 58933Y105 7,368,293 36,214 0.49 620,263 0.89 0.5469
2019-08-12 2019-06-30 13F MERCK COM 58933Y105 7,332,079 75,453 1.04 614,795 1.87 0.5528
2019-05-10 2019-03-31 13F MERCK COM 58933Y105 7,256,626 -43,937 -0.60 603,533 8.19 0.5622
2019-02-14 2018-12-31 13F MERCK COM 58933Y105 7,300,563 -46,773 -0.64 557,836 7.03 0.5945
2018-11-14 2018-09-30 13F MERCK COM 58933Y105 7,347,336 -186,436 -2.47 521,220 13.98 0.4594
2018-08-13 2018-06-30 13F MERCK COM 58933Y105 7,533,772 331,583 4.60 457,299 16.57 0.4203
2018-05-14 2018-03-31 13F MERCK COM 58933Y105 7,202,189 209,459 3.00 392,303 -0.30 0.3770
2018-02-12 2017-12-31 13F MERCK COM 58933Y105 6,992,730 140,538 2.05 393,481 -10.32 0.3623
2017-11-02 2017-09-30 13F MERCK COM 58933Y105 6,852,192 -1,160,534 -14.48 438,746 -14.56 0.4255
2017-08-08 2017-06-30 13F MERCK COM 58933Y105 8,012,726 2,304,142 40.36 513,535 41.58 0.5147
2017-05-11 2017-03-31 13F MERCK COM 58933Y105 5,708,584 -577,270 -9.18 362,723 -1.98 0.4365
2017-02-13 2016-12-31 13F MERCK COM 58933Y105 6,285,854 1,134,069 22.01 370,048 15.09 0.4694
2016-11-10 2016-09-30 13F MERCK COM 58933Y105 5,151,785 451,575 9.61 321,523 18.74 0.4246
2016-08-09 2016-06-30 13F MERCK COM 58933Y105 4,700,210 399,230 9.28 270,779 18.99 0.3777
2016-05-10 2016-03-31 13F MERCK & CO INC COM 58933Y105 4,300,980 211,921 5.18 227,565 5.36 0.3304
2016-02-09 2015-12-31 13F MERCK & CO INC COM 58933Y105 4,089,059 67,229 1.67 215,984 8.73 0.3209
2015-11-12 2015-09-30 13F/A-1 MERCK & CO INC COM 58933Y105 4,021,830 152,587 3.94 198,638 -9.82 0.3121
2015-11-09 2015-09-30 13F MERCK & CO INC COM 58933Y105 4,021,830 198,638
2015-08-10 2015-06-30 13F MERCK & CO INC COM 58933Y105 3,869,243 106,284 2.82 220,276 1.84 0.3285
2015-05-14 2015-03-31 13F/A-1 MERCK & CO INC COM 58933Y105 3,762,959 200,765 5.64 216,297 6.92 0.3222
2015-05-12 2015-03-31 13F MERCK & CO INC COM 58933Y105 3,762,959 216,295
2015-02-12 2014-12-31 13F MERCK & CO INC COM 58933Y105 3,562,194 -721,006 -16.83 202,297 -20.33 0.3143
2014-11-13 2014-09-30 13F MERCK & CO INC COM 58933Y105 4,283,200 17,834 0.42 253,908 2.90 0.4308
2014-08-12 2014-06-30 13F MERCK & CO INC COM 58933Y105 4,265,366 336,152 8.56 246,751 10.62 0.4149
2014-05-13 2014-03-31 13F MERCK & CO INC COM 58933Y105 3,929,214 586,210 17.54 223,061 33.32 0.3979
2014-02-12 2013-12-31 13F MERCK & CO INC COM 58933Y105 3,343,004 -29,300 -0.87 167,318 4.21 0.3123
2013-11-05 2013-09-30 13F MERCK & CO INC COM 58933Y105 3,372,304 -200,002 -5.60 160,556 -3.24 0.3316
2013-08-12 2013-06-30 13F MERCK & CO INC COM 58933Y105 3,572,306 3,572,306 165,933 0.3675
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.