Merck & Co., Inc.
DE ˙ XTRA ˙ US58933Y1055
102,78 € ↑2,84 (2,84%)
2026-06-04
DEL PRIS
SecurityDE:6MK / Merck & Co., Inc.
InstitutionPort Capital LLC
Latest Disclosed Ownership7,508 shares
Latest Disclosed Value $ 903,137
Port Capital LLC reports 0.99% decrease in ownership of 6MK / Merck & Co., Inc.

On May 15, 2026 - Port Capital LLC filed a 13F-HR form disclosing ownership of 7,508 shares of Merck & Co., Inc. (DE:6MK) valued at $782,334 USD as of March 31, 2026. The entity filed a previous 13F-HR on February 17, 2026 disclosing 7,583 shares of Merck & Co., Inc.. This represents a change in shares of -0.99% during the quarter. The current value of the position is $771,672 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)
2026-05-15 2026-03-31 13F MERCK COM 58933Y105 7,508 -75 -0.99 903 13.16 0.0402
2026-02-17 2025-12-31 13F MERCK COM 58933Y105 7,583 -162 -2.09 798 22.77 0.0344
2025-11-14 2025-09-30 13F MERCK COM 58933Y105 7,745 0 0.00 650 6.04 0.0271
2025-08-14 2025-06-30 13F MERCK COM 58933Y105 7,745 -581 -6.98 613 -17.94 0.0261
2025-05-15 2025-03-31 13F MERCK COM 58933Y105 8,326 15 0.18 747 -9.67 0.0339
2025-02-14 2024-12-31 13F MERCK COM 58933Y105 8,311 35 0.42 827 -12.02 0.0377
2024-11-14 2024-09-30 13F MERCK COM 58933Y105 8,276 -208 -2.45 940 -10.48 0.0421
2024-08-14 2024-06-30 13F MERCK & CO INC COM COM 58933Y105 8,484 8 0.09 1,050 -6.08 0.0526
2024-05-15 2024-03-31 13F MERCK & CO INC COM COM 58933Y105 8,476 -908 -9.68 1,118 9.29 0.0560
2024-02-15 2023-12-31 13F MERCK & CO INC COM COM 58933Y105 9,384 -16 -0.17 1,023 5.68 0.0571
2023-11-14 2023-09-30 13F MERCK & CO INC COM COM 58933Y105 9,400 57 0.61 968 -10.20 0.0604
2023-08-14 2023-06-30 13F MERCK & CO INC COM COM 58933Y105 9,343 0 0.00 1,078 8.45 0.0649
2023-05-15 2023-03-31 13F MERCK & CO INC COM COM 58933Y105 9,343 -1,488 -13.74 994 -17.30 0.0646
2023-02-15 2022-12-31 13F MERCK & CO INC COM COM 58933Y105 10,831 -245 -2.21 1,202 26.00 0.0869
2022-11-14 2022-09-30 13F MERCK & CO INC COM COM 58933Y105 11,076 56 0.51 954 -5.07 0.0775
2022-08-15 2022-06-30 13F MERCK & CO INC COM COM 58933Y105 11,020 -348 -3.06 1,005 7.72 0.0787
2022-05-16 2022-03-31 13F MERCK & CO INC COM COM 58933Y105 11,368 -867 -7.09 933 -0.53 0.0645
2022-02-14 2021-12-31 13F MERCK & CO INC COM COM 58933Y105 12,235 19 0.16 938 2.18 0.0577
2021-11-15 2021-09-30 13F MERCK & CO INC COM COM 58933Y105 12,216 -210 -1.69 918 -4.97 0.0463
2021-08-16 2021-06-30 13F MERCK & CO INC COM COM 58933Y105 12,426 72 0.58 966 1.47 0.0503
2021-05-17 2021-03-31 13F MERCK & CO. INC COM COM 58933Y105 12,354 105 0.86 952 -4.99 0.0539
2021-02-16 2020-12-31 13F MERCK & CO. INC COM COM 58933Y105 12,249 -319 -2.54 1,002 -3.93 0.0682
2020-11-16 2020-09-30 13F MERCK & CO. INC COM COM 58933Y105 12,568 22 0.18 1,043 7.53 0.0899
2020-08-17 2020-06-30 13F/A-1 MERCK & CO. INC COM COM 58933Y105 12,546 44 0.35 970 0.83 0.0935
2020-08-14 2020-06-30 13F MERCK & CO. INC COM COM 58933Y105 12,546 44 970 112,431.8310
2020-05-15 2020-03-31 13F MERCK & CO. INC COM COM 58933Y105 12,502 -289 -2.26 962 -17.28 0.1338
2020-02-14 2019-12-31 13F MERCK & CO INC COM COM 58933Y105 12,791 -395 -3.00 1,163 4.77 0.1283
2019-11-14 2019-09-30 13F MERCK & CO INC COM COM 58933Y105 13,186 -174 -1.30 1,110 -0.89 0.1267
2019-08-14 2019-06-30 13F MERCK & CO INC COM COM 58933Y105 13,360 -633 -4.52 1,120 -3.78 0.1320
2019-05-15 2019-03-31 13F MERCK & CO INC COM COM 58933Y105 13,993 -446 -3.09 1,164 5.53 0.1522
2019-02-13 2018-12-31 13F MERCK COM 58933Y105 14,439 -53 -0.37 1,103 7.30 0.1677
2018-11-14 2018-09-30 13F MERCK & CO INC COM COM 58933Y105 14,492 14,492 1,028 0.1246
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.