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

SecurityMRK / Merck & Co., Inc.
InstitutionJmac Enterprises Llc
Latest Disclosed Ownership4,819 shares
Latest Disclosed Value $ 579,715
Jmac Enterprises Llc reports 27.16% decrease in ownership of MRK / Merck & Co., Inc.

On May 1, 2026 - Jmac Enterprises Llc filed a 13F-HR form disclosing ownership of 4,819 shares of Merck & Co., Inc. (US:MRK) valued at $579,678 USD as of March 31, 2026. The entity filed a previous 13F-HR on January 21, 2026 disclosing 6,616 shares of Merck & Co., Inc.. This represents a change in shares of -27.16% during the quarter. The current value of the position is $552,739 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)
2026-05-01 2026-03-31 13F MERCK COM 58933Y105 4,819 -1,797 -27.16 580 -16.81 0.1110
2026-01-21 2025-12-31 13F MERCK COM 58933Y105 6,616 103 1.58 696 27.47 0.1331
2025-10-30 2025-09-30 13F MERCK COM 58933Y105 6,513 1,025 18.68 547 25.81 0.1081
2025-07-21 2025-06-30 13F MERCK COM 58933Y105 5,488 302 5.82 434 -6.67 0.0930
2025-04-22 2025-03-31 13F MERCK COM 58933Y105 5,186 -14,052 -73.04 465 -75.69 0.1105
2025-01-29 2024-12-31 13F MERCK COM 58933Y105 19,238 -629 -3.17 1,914 -15.20 0.3004
2024-10-31 2024-09-30 13F MERCK COM 58933Y105 19,867 1,566 8.56 2,256 -0.40 0.3603
2024-07-30 2024-06-30 13F MERCK COM 58933Y105 18,301 -8,347 -31.32 2,266 -35.58 0.3977
2024-04-30 2024-03-31 13F MERCK COM 58933Y105 26,648 10 0.04 3,516 21.07 0.6538
2024-01-26 2023-12-31 13F MERCK COM 58933Y105 26,638 -290 -1.08 2,904 4.76 0.6251
2023-10-19 2023-09-30 13F MERCK COM 58933Y105 26,928 327 1.23 2,772 -9.68 0.6845
2023-07-20 2023-06-30 13F MERCK COM 58933Y105 26,601 1,489 5.93 3,069 14.90 0.7591
2023-04-20 2023-03-31 13F MERCK COM 58933Y105 25,112 2,574 11.42 2,672 6.84 0.6786
2023-01-23 2022-12-31 13F MERCK COM 58933Y105 22,538 1,323 6.24 2,501 36.84 0.6875
2022-10-20 2022-09-30 13F MERCK COM 58933Y105 21,215 60 0.28 1,827 -5.29 0.5128
2022-07-25 2022-06-30 13F MERCK COM 58933Y105 21,155 426 2.06 1,929 13.40 0.4966
2022-05-16 2022-03-31 13F MERCK & CO INC EQUITY 58933Y105 20,729 470 2.32 1,701 9.53 0.4005
2022-02-14 2021-12-31 13F MERCK & CO INC Equity 58933Y105 20,259 20,259 1,553 0.3658
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.