Merck & Co., Inc.
MX ˙ BMV ˙ US58933Y1055
SecurityMX:MRK / Merck & Co., Inc.
InstitutionWinthrop Partners - Wny, Llc
Latest Disclosed Ownership2,722 shares
Latest Disclosed Value $ 327,429
Winthrop Partners - Wny, Llc ownership in MRK / Merck & Co., Inc.

On May 7, 2026 - Winthrop Partners - Wny, Llc filed a 13F-HR form disclosing ownership of 2,722 shares of Merck & Co., Inc. (MX:MRK) valued at $327,429 USD as of March 31, 2026. The entity filed a previous 13F-HR on March 12, 2026 disclosing 2,722 shares of Merck & Co., Inc.. This represents a change in shares of 0.00% 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)
2026-05-07 2026-03-31 13F MERCK COM 58933Y105 2,722 0 0.00 327 14.34 0.1745
2026-03-12 2025-12-31 13F MERCK COM 58933Y105 2,722 -43,232 -94.08 287 -92.61 0.1543
2019-10-28 2019-09-30 13F MERCK & COMPANY COM 58933Y105 45,954 968 2.15 3,868 2.55 2.6145
2019-08-19 2019-06-30 13F MERCK & COMPANY COM 58933Y105 44,986 2,033 4.73 3,772 5.45 2.8263
2019-05-15 2019-03-31 13F MERCK & COMPANY COM 58933Y105 42,953 1,602 3.87 3,578 13.23 2.7912
2019-01-22 2018-12-31 13F MERCK & COMPANY COM 58933Y105 41,351 50 0.12 3,160 7.85 2.9503
2018-11-15 2018-09-30 13F MERCK & COMPANY Common 58933Y105 41,301 2,788 7.24 2,930 25.33 2.3685
2018-07-30 2018-06-30 13F MERCK & COMPANY COM 58933Y105 38,513 551 1.45 2,338 9.67 1.9446
2018-06-13 2018-03-31 13F MERCK & COMPANY COM 58933Y105 37,962 170 0.45 2,132 2.30 1.6418
2018-03-14 2017-12-31 13F MERCK & COMPANY COM 58933Y105 37,792 37,792 2,084 1.7004
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.