Merck & Co., Inc.
MX ˙ BMV ˙ US58933Y1055
SecurityMX:MRK / Merck & Co., Inc.
InstitutionKeeler THomas Management LLC
Latest Disclosed Ownership12,011 shares
Latest Disclosed Value $ 1,444,796
Keeler THomas Management LLC reports 18.56% decrease in ownership of MRK / Merck & Co., Inc.

On May 12, 2026 - Keeler THomas Management LLC filed a 13F-HR form disclosing ownership of 12,011 shares of Merck & Co., Inc. (MX:MRK) valued at $1,444,796 USD as of March 31, 2026. The entity filed a previous 13F-HR on February 12, 2026 disclosing 14,749 shares of Merck & Co., Inc.. This represents a change in shares of -18.56% 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)
2026-05-12 2026-03-31 13F MERCK COM 58933Y105 12,011 -2,738 -18.56 1,445 -6.96 0.6115
2026-02-12 2025-12-31 13F MERCK COM 58933Y105 14,749 50 0.34 1,552 25.87 0.7399
2025-11-04 2025-09-30 13F MERCK COM 58933Y105 14,699 283 1.96 1,234 8.06 0.5034
2025-07-31 2025-06-30 13F MERCK COM 58933Y105 14,416 7,453 107.04 1,141 82.85 0.4911
2025-05-09 2025-03-31 13F MERCK COM 58933Y105 6,963 -3,606 -34.12 625 -40.63 0.3062
2025-02-04 2024-12-31 13F MERCK COM 58933Y105 10,569 30 0.28 1,051 -12.12 0.3747
2024-10-17 2024-09-30 13F MERCK COM 58933Y105 10,539 -199 -1.85 1,197 -10.01 0.3785
2024-07-23 2024-06-30 13F MERCK COM 58933Y105 10,738 -848 -7.32 1,329 -13.02 0.4530
2024-05-07 2024-03-31 13F MERCK COM 58933Y105 11,586 -4,024 -25.78 1,529 -10.17 0.5241
2024-02-01 2023-12-31 13F MERCK COM 58933Y105 15,610 -1,100 -6.58 1,702 -1.10 0.6712
2023-10-26 2023-09-30 13F MERCK COM 58933Y105 16,710 -302 -1.78 1,720 -12.33 0.6364
2023-07-21 2023-06-30 13F MERCK COM 58933Y105 17,012 -900 -5.02 1,963 2.99 0.7928
2023-05-02 2023-03-31 13F MERCK COM 58933Y105 17,912 -6,184 -25.66 1,906 -28.73 0.8956
2023-01-20 2022-12-31 13F MERCK COM 58933Y105 24,096 -227 -0.93 2,673 27.65 1.3474
2022-10-24 2022-09-30 13F MERCK COM 58933Y105 24,323 19,053 361.54 2,094 335.34 1.0636
2022-07-29 2022-06-30 13F MERCK COM 58933Y105 5,270 -76 -1.42 481 9.57 0.2382
2022-04-28 2022-03-31 13F MERCK COM 58933Y105 5,346 1,265 31.00 439 40.71 0.2108
2022-01-24 2021-12-31 13F MERCK COM 58933Y105 4,081 -43,295 -91.39 312 -91.25 0.1350
2021-10-15 2021-09-30 13F MERCK COM 58933Y105 47,376 2,388 5.31 3,564 1.89 1.6968
2021-07-27 2021-06-30 13F MERCK COM 58933Y105 44,988 -2,380 -5.02 3,498 -4.19 1.7102
2021-04-23 2021-03-31 13F MERCK CO. COM 58933Y105 47,368 5,421 12.92 3,651 6.35 1.9227
2021-01-26 2020-12-31 13F MERCK &CO. COM 58933Y105 41,947 2,957 7.58 3,433 6.32 1.9323
2020-11-02 2020-09-30 13F MERCK &CO. COM 58933Y105 38,990 38,990 3,229 2.0348
2018-05-07 2018-03-31 13F MERCK COM 58933Y105 0 -311 -100.00 0 -100.00
2018-02-07 2017-12-31 13F MERCK COM 58933Y105 311 311 17 0.0156
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.