Merck & Co., Inc.
BG ˙ BUL ˙ US58933Y1055
SecurityBG:6MK / Merck & Co., Inc.
InstitutionProShare Advisors LLC
Latest Disclosed Ownership525,295 shares
Latest Disclosed Value $ 63,187,736
ProShare Advisors LLC reports 16.47% decrease in ownership of 6MK / Merck & Co., Inc.

On April 24, 2026 - ProShare Advisors LLC filed a 13F-HR form disclosing ownership of 525,295 shares of Merck & Co., Inc. (BG:6MK) valued at $63,187,736 USD as of March 31, 2026. The entity filed a previous 13F-HR on February 6, 2026 disclosing 628,875 shares of Merck & Co., Inc.. This represents a change in shares of -16.47% 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)
2026-04-24 2026-03-31 13F MERCK COM 58933Y105 525,295 -103,580 -16.47 63,188 -4.54 0.0936
2026-02-06 2025-12-31 13F MERCK COM 58933Y105 628,875 45,109 7.73 66,195 35.11 0.1168
2025-11-06 2025-09-30 13F MERCK COM 58933Y105 583,766 -27,967 -4.57 48,995 1.18 0.1025
2025-08-07 2025-06-30 13F MERCK COM 58933Y105 611,733 37,005 6.44 48,425 -6.13 0.0966
2025-05-08 2025-03-31 13F MERCK COM 58933Y105 574,728 -16,339 -2.76 51,588 -12.27 0.1164
2025-02-14 2024-12-31 13F MERCK COM 58933Y105 591,067 89,745 17.90 58,799 3.28 0.1344
2024-11-14 2024-09-30 13F MERCK COM 58933Y105 501,322 -20,331 -3.90 56,930 -11.85 0.1395
2024-08-13 2024-06-30 13F MERCK COM 58933Y105 521,653 34,574 7.10 64,581 0.48 0.1728
2024-05-08 2024-03-31 13F MERCK COM 58933Y105 487,079 -43,822 -8.25 64,270 11.04 0.1709
2024-02-14 2023-12-31 13F MERCK COM 58933Y105 530,901 -36,530 -6.44 57,879 -0.92 0.1769
2023-11-13 2023-09-30 13F MERCK COM 58933Y105 567,431 -35,302 -5.86 58,417 -16.01 0.1821
2023-08-10 2023-06-30 13F MERCK COM 58933Y105 602,733 -8,106 -1.33 69,549 7.02 0.2017
2023-05-26 2023-03-31 13F/A-1 MERCK COM 58933Y105 610,839 62,941 11.49 64,987 6.91 0.1986
2023-05-12 2023-03-31 13F MERCK COM 58933Y105 610,839 62,941 64,987 0.2067
2023-02-02 2022-12-31 13F MERCK COM 58933Y105 547,898 18,198 3.44 60,789 33.26 0.2135
2022-11-07 2022-09-30 13F MERCK COM 58933Y105 529,700 -35,416 -6.27 45,618 -11.46 0.1750
2022-08-01 2022-06-30 13F MERCK COM 58933Y105 565,116 -218,960 -27.93 51,521 -19.92 0.1709
2022-05-10 2022-03-31 13F MERCK COM 58933Y105 784,076 -34,725 -4.24 64,334 2.52 0.1382
2022-02-08 2021-12-31 13F MERCK COM 58933Y105 818,801 186,485 29.49 62,754 32.13 0.1231
2021-11-12 2021-09-30 13F MERCK COM 58933Y105 632,316 -22,451 -3.43 47,493 -6.73 0.1334
2021-08-13 2021-06-30 13F MERCK COM 58933Y105 654,767 82,428 14.40 50,921 15.41 0.1489
2021-05-14 2021-03-31 13F MERCK & CO. COM 58933Y105 572,339 55,720 10.79 44,122 4.41 0.1387
2021-02-09 2020-12-31 13F MERCK & CO. COM 58933Y105 516,619 1,029 0.20 42,259 -1.19 0.1572
2020-11-13 2020-09-30 13F MERCK & CO. COM 58933Y105 515,590 -52,897 -9.30 42,768 -2.71 0.1977
2020-08-03 2020-06-30 13F MERCK & CO. COM 58933Y105 568,487 96,559 20.46 43,961 21.07 0.2348
2020-05-15 2020-03-31 13F MERCK & CO. COM 58933Y105 471,928 -202,032 -29.98 36,310 -40.76 0.2609
2020-02-12 2019-12-31 13F MERCK COM 58933Y105 673,960 116,912 20.99 61,297 30.72 0.2838
2019-11-12 2019-09-30 13F MERCK COM 58933Y105 557,048 46,279 9.06 46,892 9.49 0.2625
2019-08-13 2019-06-30 13F MERCK COM 58933Y105 510,769 -108,893 -17.57 42,828 -16.90 0.2561
2019-05-15 2019-03-31 13F MERCK COM 58933Y105 619,662 11,900 1.96 51,537 10.98 0.3084
2019-02-14 2018-12-31 13F MERCK COM 58933Y105 607,762 100,771 19.88 46,439 29.12 0.3250
2018-11-14 2018-09-30 13F MERCK COM 58933Y105 506,991 -131,130 -20.55 35,966 -7.15 0.2442
2018-08-13 2018-06-30 13F MERCK COM 58933Y105 638,121 -91,005 -12.48 38,734 -2.47 0.2596
2018-05-14 2018-03-31 13F MERCK COM 58933Y105 729,126 43,839 6.40 39,715 2.99 0.2587
2018-02-14 2017-12-31 13F MERCK COM 58933Y105 685,287 251,160 57.85 38,561 38.72 0.2675
2017-11-13 2017-09-30 13F MERCK COM 58933Y105 434,127 51,456 13.45 27,797 13.34 0.2555
2017-08-11 2017-06-30 13F MERCK COM 58933Y105 382,671 -42,021 -9.89 24,525 -9.12 0.2443
2017-05-12 2017-03-31 13F/A-2 MERCK COM 58933Y105 424,692 -3,833 -0.89 26,985 6.97 0.2822
2017-05-08 2017-03-31 13F/A-1 MERCK COM 58933Y105 424,692 0 26,985 0.2822
2017-04-25 2017-03-31 13F MERCK COM 58933Y105 424,692 26,985
2017-02-13 2016-12-31 13F MERCK COM 58933Y105 428,525 97,100 29.30 25,227 21.96 0.2793
2016-11-10 2016-09-30 13F MERCK COM 58933Y105 331,425 -129,521 -28.10 20,684 -22.11 0.2888
2016-08-12 2016-06-30 13F MERCK COM 58933Y105 460,946 -20,186 -4.20 26,555 4.31 0.3421
2016-05-06 2016-03-31 13F MERCK & CO INC COM 58933Y105 481,132 -179,050 -27.12 25,457 -27.00 0.3504
2016-02-05 2015-12-31 13F MERCK & CO INC COM 58933Y105 660,182 11,680 1.80 34,871 8.87 0.4224
2015-11-06 2015-09-30 13F MERCK & CO INC COM 58933Y105 648,502 33,684 5.48 32,030 -8.49 0.4499
2015-08-11 2015-06-30 13F MERCK & CO INC COM 58933Y105 614,818 -114,341 -15.68 35,002 -16.49 0.4843
2015-05-08 2015-03-31 13F MERCK & CO INC COM 58933Y105 729,159 729,159 0.00 41,912 0.4937
2015-01-30 2014-12-31 13F MERCK & CO INC COM 58933Y105 0 -638,880 -100.00 0 -100.00
2014-11-06 2014-09-30 13F MERCK & CO INC COM 58933Y105 638,880 -56,481 -8.12 37,873 -5.85 0.5021
2014-08-08 2014-06-30 13F MERCK & CO INC COM 58933Y105 695,361 -33,580 -4.61 40,227 -2.79 0.5212
2014-05-07 2014-03-31 13F MERCK & CO INC COM 58933Y105 728,941 40,857 5.94 41,382 20.16 0.5175
2014-02-04 2013-12-31 13F MERCK & CO INC COM 58933Y105 688,084 308,687 81.36 34,439 90.66 0.5132
2013-11-07 2013-09-30 13F MERCK & CO INC COM 58933Y105 379,397 -231,991 -37.94 18,063 -36.40 0.4287
2013-07-25 2013-06-30 13F MERCK & CO INC COM 58933Y105 611,388 611,388 28,399 0.5574
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.