Merck & Co., Inc.
MX ˙ BMV ˙ US58933Y1055
SecurityMX:MRK / Merck & Co., Inc.
InstitutionNissay Asset Management Corp /japan/ /adv
Latest Disclosed Ownership329,632 shares
Latest Disclosed Value $ 39,651,433
Nissay Asset Management Corp /japan/ /adv reports 0.96% decrease in ownership of MRK / Merck & Co., Inc.

On May 15, 2026 - Nissay Asset Management Corp /japan/ /adv filed a 13F-HR form disclosing ownership of 329,632 shares of Merck & Co., Inc. (MX:MRK) valued at $39,651,433 USD as of March 31, 2026. The entity filed a previous 13F-HR on February 17, 2026 disclosing 332,835 shares of Merck & Co., Inc.. This represents a change in shares of -0.96% 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 329,632 -3,203 -0.96 39,651 13.18 0.2101
2026-02-17 2025-12-31 13F MERCK COM 58933Y105 332,835 2,186 0.66 35,034 26.24 0.1822
2025-11-14 2025-09-30 13F MERCK COM 58933Y105 330,649 -7,132 -2.11 27,751 3.79 0.1533
2025-08-14 2025-06-30 13F MERCK COM 58933Y105 337,781 10,841 3.32 26,739 -8.89 0.1565
2025-05-15 2025-03-31 13F MERCK COM 58933Y105 326,940 1,621 0.50 29,346 -9.52 0.1907
2025-02-14 2024-12-31 13F MERCK COM 58933Y105 325,319 8,041 2.53 32,434 -9.98 0.1978
2024-11-14 2024-09-30 13F MERCK COM 58933Y105 317,278 6,150 1.98 36,030 -6.46 0.2281
2024-08-14 2024-06-30 13F MERCK COM 58933Y105 311,128 7,275 2.39 38,518 -3.93 0.2550
2024-05-15 2024-03-31 13F MERCK COM 58933Y105 303,853 -181 -0.06 40,093 20.96 0.2778
2024-02-14 2023-12-31 13F MERCK COM 58933Y105 304,034 -6,594 -2.12 33,146 3.65 0.2666
2023-11-14 2023-09-30 13F MERCK COM 58933Y105 310,628 6,270 2.06 31,979 -8.94 0.2835
2023-08-14 2023-06-30 13F MERCK COM 58933Y105 304,358 -4,223 -1.37 35,120 6.98 0.3029
2023-05-15 2023-03-31 13F MERCK COM 58933Y105 308,581 -10,783 -3.38 32,830 -7.35 0.2933
2023-02-14 2022-12-31 13F MERCK COM 58933Y105 319,364 -26,812 -7.75 35,433 18.85 0.3387
2022-11-14 2022-09-30 13F MERCK COM 58933Y105 346,176 27,242 8.54 29,813 2.53 0.3130
2022-08-15 2022-06-30 13F MERCK COM 58933Y105 318,934 11,123 3.61 29,077 15.13 0.2894
2022-05-16 2022-03-31 13F MERCK COM 58933Y105 307,811 4,616 1.52 25,256 8.69 0.2200
2022-02-14 2021-12-31 13F MERCK COM 58933Y105 303,195 3,469 1.16 23,237 3.22 0.1780
2021-11-10 2021-09-30 13F MERCK COM 58933Y105 299,726 -2,243 -0.74 22,512 -4.14 0.1908
2021-08-13 2021-06-30 13F MERCK COM 58933Y105 301,969 10,223 3.50 23,484 4.42 0.2062
2021-05-11 2021-03-31 13F MERCK & CO. COM 58933Y105 291,746 -7,579 -2.53 22,491 -8.14 0.2217
2021-02-08 2020-12-31 13F MERCK & CO. COM 58933Y105 299,325 -40,365 -11.88 24,485 -13.10 0.3681
2020-10-20 2020-09-30 13F MERCK & CO. COM 58933Y105 339,690 -38,947 -10.29 28,177 -3.77 0.4760
2020-07-27 2020-06-30 13F MERCK & CO. COM 58933Y105 378,637 9,201 2.49 29,280 3.01 0.5682
2020-05-05 2020-03-31 13F MERCK & CO. COM 58933Y105 369,436 6,786 1.87 28,424 -13.82 0.7237
2020-02-14 2019-12-31 13F MERCK COM 58933Y105 362,650 25,720 7.63 32,983 16.29 0.7330
2019-11-14 2019-09-30 13F MERCK COM 58933Y105 336,930 -65,612 -16.30 28,363 -15.97 0.7019
2019-08-07 2019-06-30 13F MERCK COM 58933Y105 402,542 -13,416 -3.23 33,753 -2.43 0.8532
2019-05-03 2019-03-31 13F MERCK COM 58933Y105 415,958 -43,135 -9.40 34,595 -1.38 0.9141
2019-02-06 2018-12-31 13F MERCK COM 58933Y105 459,093 42,721 10.26 35,079 18.76 1.0690
2018-10-30 2018-09-30 13F MERCK COM 58933Y105 416,372 94,491 29.36 29,537 51.18 0.7947
2018-08-08 2018-06-30 13F MERCK COM 58933Y105 321,881 -19,878 -5.82 19,538 4.95 0.5716
2018-05-14 2018-03-31 13F MERCK COM 58933Y105 341,759 -21,246 -5.85 18,616 -8.87 0.5817
2018-02-14 2017-12-31 13F MERCK COM 58933Y105 363,005 363,005 20,429 0.6221
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.