Merck & Co., Inc.
MX ˙ BMV ˙ US58933Y1055
SecurityMX:MRK / Merck & Co., Inc.
InstitutionDempze Nancy E
Latest Disclosed Ownership5,455 shares
Latest Disclosed Value $ 656,181
Dempze Nancy E reports 12.09% decrease in ownership of MRK / Merck & Co., Inc.

On May 14, 2026 - Dempze Nancy E filed a 13F-HR form disclosing ownership of 5,455 shares of Merck & Co., Inc. (MX:MRK) valued at $656,181 USD as of March 31, 2026. The entity filed a previous 13F-HR on February 14, 2026 disclosing 6,205 shares of Merck & Co., Inc.. This represents a change in shares of -12.09% 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)
2026-05-14 2026-03-31 13F MERCK COM 58933Y105 5,455 -750 -12.09 656 0.46 0.0704
2026-02-14 2025-12-31 13F MERCK COM 58933Y105 6,205 525 9.24 653 37.18 0.3403
2025-11-10 2025-09-30 13F MERCK COM 58933Y105 5,680 -1,535 -21.28 477 -16.64 0.2618
2025-07-23 2025-06-30 13F MERCK COM 58933Y105 7,215 -1,490 -17.12 571 -26.89 0.3294
2025-05-06 2025-03-31 13F MERCK COM 58933Y105 8,705 -1,650 -15.93 781 -24.17 0.4691
2025-02-13 2024-12-31 13F MERCK COM 58933Y105 10,355 0 0.00 1,030 -12.34 0.5949
2024-11-12 2024-09-30 13F MERCK COM 58933Y105 10,355 5,950 135.07 1,176 115.60 0.6561
2024-08-12 2024-06-30 13F MERCK COM 58933Y105 4,405 1,000 29.37 545 21.38 0.3743
2024-05-14 2024-03-31 13F MERCK COM 58933Y105 3,405 -215 -5.94 449 13.96 0.3421
2024-02-14 2023-12-31 13F MERCK COM 58933Y105 3,620 -50 -1.36 395 4.51 0.3301
2023-11-14 2023-09-30 13F MERCK COM 58933Y105 3,670 -95 -2.52 378 -13.13 0.3393
2023-08-14 2023-06-30 13F MERCK COM 58933Y105 3,765 0 0.00 434 8.50 0.3724
2023-05-11 2023-03-31 13F MERCK COM 58933Y105 3,765 0 0.00 401 -4.08 0.3644
2023-02-09 2022-12-31 13F MERCK COM 58933Y105 3,765 0 0.00 418 28.31 0.4075
2022-11-08 2022-09-30 13F MERCK COM 58933Y105 3,765 0 0.00 325 -5.25 0.3460
2022-07-19 2022-06-30 13F MERCK COM 58933Y105 3,765 0 0.00 343 11.00 0.3446
2022-05-17 2022-03-31 13F MERCK COM 58933Y105 3,765 -47 -1.23 309 6.19 0.2257
2022-02-08 2021-12-31 13F MERCK COM 58933Y105 3,812 -58 -1.50 291 0.00 0.1964
2021-11-10 2021-09-30 13F MERCK COM 58933Y105 3,870 -150 -3.73 291 -7.03 0.2283
2021-08-09 2021-06-30 13F MERCK COM 58933Y105 4,020 55 1.39 313 2.29 0.2639
2021-05-17 2021-03-31 13F MERCK COM 58933Y105 3,965 -3,400 -46.16 306 -49.25 0.2705
2021-02-16 2020-12-31 13F MERCK COM 58933Y105 7,365 0 0.00 603 -1.31 0.5540
2020-10-28 2020-09-30 13F MERCK COM 58933Y105 7,365 -450 -5.76 611 1.16 0.6201
2020-07-28 2020-06-30 13F MERCK COM 58933Y105 7,815 -25 -0.32 604 0.17 0.6746
2020-05-07 2020-03-31 13F MERCK COM 58933Y105 7,840 -123 -1.54 603 -16.71 0.8108
2020-01-15 2019-12-31 13F MERCK COM 58933Y105 7,963 -125 -1.55 724 6.47 0.8015
2019-11-07 2019-09-30 13F MERCK COM 58933Y105 8,088 -200 -2.41 680 -2.30 0.8231
2019-07-24 2019-06-30 13F MERCK COM 58933Y105 8,288 -100 -1.19 696 -0.29 0.7985
2019-05-01 2019-03-31 13F MERCK COM 58933Y105 8,388 -467 -5.27 698 3.10 0.8233
2019-01-24 2018-12-31 13F MERCK COM 58933Y105 8,855 -419 -4.52 677 2.89 0.9408
2018-10-15 2018-09-30 13F MERCK COM 58933Y105 9,274 -10 -0.11 658 16.67 0.7372
2018-07-30 2018-06-30 13F MERCK COM 58933Y105 9,284 -4,904 -34.56 564 -27.04 0.6897
2018-04-24 2018-03-31 13F MERCK COM 58933Y105 14,188 -301 -2.08 773 -5.15 0.9535
2018-02-02 2017-12-31 13F MERCK COM 58933Y105 14,489 202 1.41 815 -10.83 0.9837
2017-10-26 2017-09-30 13F MERCK COM 58933Y105 14,287 -25 -0.17 914 -0.44 1.2876
2017-07-26 2017-06-30 13F MERCK COM 58933Y105 14,312 -63 -0.44 918 0.55 1.3168
2017-05-15 2017-03-31 13F MERCK COM 58933Y105 14,375 2,317 19.22 913 28.59 1.3976
2017-02-14 2016-12-31 13F MERCK Common Stock 58933Y105 12,058 0 0.00 710 -5.59 1.2439
2016-11-15 2016-09-30 13F MERCK Common Stock 58933Y105 12,058 -25 -0.21 752 8.05 1.3168
2016-08-08 2016-06-30 13F MERCK Common Stock 58933Y105 12,083 0 0.00 696 8.92 1.2392
2016-05-27 2016-03-31 13F MERCK Common Stock 58933Y105 12,083 -700 -5.48 639 -5.33 1.1208
2016-02-12 2015-12-31 13F MERCK Common Stock 58933Y105 12,783 12,783 675 1.2989
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.