Merck & Co., Inc.
US ˙ NYSE ˙ US58933Y1055

SecurityMRK / Merck & Co., Inc.
InstitutionWhittier Trust Co
Latest Disclosed Ownership585,422 shares
Latest Disclosed Value $ 70,748,267
Whittier Trust Co reports 4.92% increase in ownership of MRK / Merck & Co., Inc.

On April 28, 2026 - Whittier Trust Co filed a 13F-HR form disclosing ownership of 585,422 shares of Merck & Co., Inc. (US:MRK) valued at $70,420,412 USD as of March 31, 2026. The entity filed a previous 13F-HR on January 26, 2026 disclosing 557,983 shares of Merck & Co., Inc.. This represents a change in shares of 4.92% during the quarter. The current value of the position is $67,147,903 USD.

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)
2026-04-28 2026-03-31 13F MERCK common 58933Y105 585,422 27,439 4.92 70,748 16.46 0.7984
2026-01-26 2025-12-31 13F MERCK common 58933Y105 557,983 18,574 3.44 60,748 26.27 0.6578
2025-10-31 2025-09-30 13F MERCK common 58933Y105 539,409 696 0.13 48,110 12.83 0.5476
2025-07-30 2025-06-30 13F MERCK & CO INC COM US LARGE-CAP EQUITIES 58933Y105 538,713 28,237 5.53 42,638 -6.94 0.5141
2025-05-02 2025-03-31 13F MERCK & CO INC COM US LARGE-CAP EQUITIES 58933Y105 510,476 2,446 0.48 45,820 -9.34 0.6383
2025-02-11 2024-12-31 13F MERCK & CO INC COM US LARGE-CAP EQUITIES 58933Y105 508,030 1,346 0.27 50,538 -12.17 0.6658
2024-10-21 2024-09-30 13F MERCK & CO INC COM US LARGE-CAP EQUITIES 58933Y105 506,684 8,734 1.75 57,538 -6.66 0.7700
2024-07-29 2024-06-30 13F MERCK & CO INC COM US LARGE-CAP EQUITIES 58933Y105 497,950 5,005 1.02 61,646 -5.22 0.8745
2024-05-02 2024-03-31 13F MERCK & CO INC COM US LARGE-CAP EQUITIES 58933Y105 492,945 45,350 10.13 65,044 33.30 0.9483
2024-01-11 2023-12-31 13F MERCK & CO INC COM US LARGE-CAP EQUITIES 58933Y105 447,595 3,852 0.87 48,796 6.82 0.7911
2023-10-27 2023-09-30 13F MERCK & CO INC COM US LARGE-CAP EQUITIES 58933Y105 443,743 4,785 1.09 45,683 -9.81 0.8119
2023-07-24 2023-06-30 13F MERCK & CO INC COM US LARGE-CAP EQUITIES 58933Y105 438,958 -11,836 -2.63 50,651 5.61 0.8804
2023-04-21 2023-03-31 13F MERCK & CO INC COM US LARGE-CAP EQUITIES 58933Y105 450,794 8,755 1.98 47,959 -2.21 0.8731
2023-01-25 2022-12-31 13F MERCK & CO INC COM US LARGE-CAP EQUITIES 58933Y105 442,039 -1,565 -0.35 49,044 28.37 0.9540
2022-10-21 2022-09-30 13F MERCK & CO INC COM US LARGE-CAP EQUITIES 58933Y105 443,604 13,911 3.24 38,203 -2.48 0.8007
2022-07-28 2022-06-30 13F MERCK & CO INC COM US LARGE-CAP EQUITIES 58933Y105 429,693 1,639 0.38 39,175 11.54 0.7913
2022-04-29 2022-03-31 13F MERCK & CO INC COM US LARGE-CAP EQUITIES 58933Y105 428,054 15,827 3.84 35,121 11.18 0.5923
2022-01-19 2021-12-31 13F MERCK & CO INC COM US LARGE-CAP EQUITIES 58933Y105 412,227 7,293 1.80 31,589 3.86 0.5133
2021-11-01 2021-09-30 13F MERCK & CO INC COM US LARGE-CAP EQUITIES 58933Y105 404,934 -3,775 -0.92 30,414 -4.31 0.5538
2021-07-29 2021-06-30 13F MERCK & CO INC COM US LARGE-CAP EQUITIES 58933Y105 408,709 8,008 2.00 31,785 2.90 0.5662
2021-04-26 2021-03-31 13F MERCK & CO INC COM US LARGE-CAP EQUITIES 58933Y105 400,701 17,041 4.44 30,890 -1.57 0.6000
2021-01-29 2020-12-31 13F MERCK & CO INC COM US LARGE-CAP EQUITIES 58933Y105 383,660 9,905 2.65 31,383 1.23 0.6703
2020-10-30 2020-09-30 13F MERCK & CO INC COM US LARGE-CAP EQUITIES 58933Y105 373,755 3,377 0.91 31,003 8.25 0.7381
2020-07-10 2020-06-30 13F MERCK & CO INC COM US LARGE-CAP EQUITIES 58933Y105 370,378 52,334 16.45 28,641 17.05 0.7954
2020-04-27 2020-03-31 13F MERCK & CO INC COM US LARGE-CAP EQUITIES 58933Y105 318,044 3,785 1.20 24,470 -14.39 0.7989
2020-01-31 2019-12-31 13F MERCK & CO INC COM US LARGE-CAP EQUITIES 58933Y105 314,259 4,140 1.33 28,582 9.49 0.7499
2019-10-18 2019-09-30 13F MERCK & CO INC COM US LARGE-CAP EQUITIES 58933Y105 310,119 16,011 5.44 26,105 5.86 0.7471
2019-07-23 2019-06-30 13F MERCK & CO INC COM US LARGE-CAP EQUITIES 58933Y105 294,108 7,111 2.48 24,660 3.31 0.7242
2019-04-29 2019-03-31 13F MERCK & CO INC COM US LARGE-CAP EQUITIES 58933Y105 286,997 643 0.22 23,870 9.11 0.7299
2019-02-07 2018-12-31 13F MERCK & CO INC COM US LARGE-CAP EQUITIES 58933Y105 286,354 28,812 11.19 21,878 19.75 0.7527
2018-10-23 2018-09-30 13F MERCK & CO INC COM US LARGE-CAP EQUITIES 58933Y105 257,542 -5,884 -2.23 18,270 14.26 0.5700
2018-07-27 2018-06-30 13F/A-1 MERCK & CO INC COM US LARGE-CAP EQUITIES 58933Y105 263,426 -3,436 -1.29 15,990 10.00 0.5282
2018-07-20 2018-06-30 13F MERCK & CO INC COM US LARGE CAP EQUITIES 58933Y105 274,458 7,596 15,875
2018-05-01 2018-03-31 13F MERCK & CO INC COM US LARGE-CAP EQUITIES 58933Y105 266,862 7,625 2.94 14,536 -0.35 0.4883
2018-02-07 2017-12-31 13F MERCK & CO INC COM US LARGE-CAP EQUITIES 58933Y105 259,237 -22,471 -7.98 14,587 -19.12 0.5088
2017-10-23 2017-09-30 13F MERCK & CO INC COM US LARGE-CAP EQUITIES 58933Y105 281,708 -2,703 -0.95 18,035 -1.06 0.6573
2017-07-20 2017-06-30 13F MERCK & CO INC COM US LARGE-CAP EQUITIES 58933Y105 284,411 4,970 1.78 18,228 2.66 0.7047
2017-04-26 2017-03-31 13F MERCK US LARGE CAP EQUITIES 58933Y105 279,441 373 0.13 17,756 8.10 0.7163
2017-01-18 2016-12-31 13F MERCK & CO INC COM US LARGE CAP EQUITIES 58933Y105 279,068 -2,107 -0.75 16,425 -6.38 0.6987
2016-11-10 2016-09-30 13F MERCK & CO INC COM US LARGE CAP EQUITIES 58933Y105 281,175 -2,715 -0.96 17,545 7.28 0.7642
2016-07-28 2016-06-30 13F MERCK & CO INC COM US LARGE CAP EQUITIES 58933Y105 283,890 -8,774 -3.00 16,355 5.64 0.7205
2016-04-28 2016-03-31 13F MERCK & CO INC COM US LARGE CAP EQUITIES 58933Y105 292,664 -1,167 -0.40 15,482 -0.23 0.6846
2016-02-10 2015-12-31 13F MERCK & CO INC COM US LARGE CAP EQUITIES 58933Y105 293,831 193 0.07 15,517 7.01 0.7041
2015-11-12 2015-09-30 13F MERCK & CO INC COM US LARGE CAP EQUITIES 58933Y105 293,638 -3,737 -1.26 14,500 -14.35 0.7053
2015-08-13 2015-06-30 13F MERCK & CO INC COM US LARGE CAP EQUITIES 58933Y105 297,375 593 0.20 16,930 -0.73 0.7515
2015-05-05 2015-03-31 13F MERCK & CO INC COM US LARGE CAP EQUITIES 58933Y105 296,782 296,782 0.00 17,055 0.7817
2015-02-04 2014-12-31 13F MERCK & CO INC COM US LARGE CAP EQUITIES 58933Y105 0 -291,069 -100.00 0 -100.00
2014-11-07 2014-09-30 13F MERCK & CO INC COM US LARGE CAP EQUITIES 58933Y105 291,069 7,401 2.61 17,251 5.14 0.8406
2014-08-04 2014-06-30 13F MERCK & CO INC COM US LARGE CAP EQUITIES 58933Y105 283,668 -4,876 -1.69 16,408 0.16 0.8091
2014-05-01 2014-03-31 13F MERCK & CO INC COM US LARGE CAP EQUITIES 58933Y105 288,544 1,027 0.36 16,381 13.85 0.8393
2014-02-05 2013-12-31 13F MERCK & CO INC COM US LARGE CAP EQUITIES 58933Y105 287,517 -6,114 -2.08 14,388 2.94 0.7378
2013-11-18 2013-09-30 13F MERCK COM 58933Y105 293,631 4,027 1.39 13,977 3.91 0.7562
2013-08-14 2013-06-30 13F MERCK COM 58933Y105 289,604 289,604 13,451 0.7537
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.