Merck & Co., Inc.
MX ˙ BMV ˙ US58933Y1055
SecurityMX:MRK / Merck & Co., Inc.
InstitutionFirst County Bank /CT/
Latest Disclosed Ownership18,936 shares
Latest Disclosed Value $ 2,277,811
First County Bank /CT/ reports 0.34% decrease in ownership of MRK / Merck & Co., Inc.

On April 3, 2026 - First County Bank /CT/ filed a 13F-HR form disclosing ownership of 18,936 shares of Merck & Co., Inc. (MX:MRK) valued at $2,277,811 USD as of March 31, 2026. The entity filed a previous 13F-HR on January 14, 2026 disclosing 19,001 shares of Merck & Co., Inc.. This represents a change in shares of -0.34% 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)
2026-04-03 2026-03-31 13F Merck & Co Inc Equities 58933Y105 18,936 -65 -0.34 2,278 13.85 1.2160
2026-01-14 2025-12-31 13F Merck & Co Inc Equities 58933Y105 19,001 -905 -4.55 2,000 19.76 1.0473
2025-10-08 2025-09-30 13F Merck & Co Inc Equities 58933Y105 19,906 192 0.97 1,671 7.05 0.8526
2025-07-17 2025-06-30 13F Merck & Co Inc Equities 58933Y105 19,714 1,529 8.41 1,561 -4.41 0.8392
2025-04-07 2025-03-31 13F Merck & Co Inc Equities 58933Y105 18,185 836 4.82 1,632 -5.39 0.9017
2025-01-07 2024-12-31 13F Merck & Co Inc Equities 58933Y105 17,349 -2,560 -12.86 1,726 -23.67 0.9643
2024-11-12 2024-09-30 13F Merck & Co Inc Equities 58933Y105 19,909 -237 -1.18 2,261 -9.38 1.1163
2024-08-15 2024-06-30 13F Merck & Co Inc Equities 58933Y105 20,146 -1,059 -4.99 2,494 -10.86 1.2827
2024-05-14 2024-03-31 13F Merck & Co Inc Equities 58933Y105 21,205 -999 -4.50 2,798 15.62 1.3674
2024-02-14 2023-12-31 13F Merck & Co Inc Equities 58933Y105 22,204 -1,097 -4.71 2,421 0.92 1.1733
2023-11-07 2023-09-30 13F Merck & Co Inc Equities 58933Y105 23,301 446 1.95 2,399 -9.06 1.2484
2023-07-18 2023-06-30 13F Merck & Co Inc Equities 58933Y105 22,855 -2,751 -10.74 2,637 -3.19 1.2799
2023-07-18 2023-03-31 13F Merck & Co Inc Equities 58933Y105 25,606 -21,178 -45.27 2,724 -47.51 1.3359
2023-07-18 2022-12-31 13F Merck & Co Inc Equities 58933Y105 46,784 46,784 5,191 2.4891
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.