Merck & Co., Inc.
MX ˙ BMV ˙ US58933Y1055
SecurityMX:MRK / Merck & Co., Inc.
InstitutionMark Sheptoff Financial Planning, Llc
Latest Disclosed Ownership400 shares
Latest Disclosed Value $ 45,260
Mark Sheptoff Financial Planning, Llc reports 71.43% decrease in ownership of MRK / Merck & Co., Inc.

On May 11, 2026 - Mark Sheptoff Financial Planning, Llc filed a 13F-HR form disclosing ownership of 400 shares of Merck & Co., Inc. (MX:MRK) valued at $45,260 USD as of March 31, 2026. The entity filed a previous 13F-HR on February 12, 2026 disclosing 1,400 shares of Merck & Co., Inc.. This represents a change in shares of -71.43% 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)
2026-05-11 2026-03-31 13F MERCK &CO. COM 58933Y105 400 -1,000 -71.43 45 -69.39 0.0240
2026-02-12 2025-12-31 13F MERCK COM 58933Y105 1,400 0 0.00 147 25.64 0.0702
2025-11-13 2025-09-30 13F MERCK OM 58933Y105 1,400 0 0.00 118 6.36 0.0562
2025-08-06 2025-06-30 13F MERCK COM 58933Y105 1,400 -3,668 -72.38 111 -75.77 0.0591
2025-05-13 2025-03-31 13F MERCK COM 58933Y105 5,068 -1,850 -26.74 455 -34.01 0.2508
2025-02-12 2024-12-31 13F MERCK COM 58933Y105 6,918 -550 -7.36 688 -18.87 0.3692
2024-11-14 2024-09-30 13F MERCK COM 58933Y105 7,468 -800 -9.68 848 -17.11 0.4506
2024-08-12 2024-06-30 13F MERCK COM 58933Y105 8,268 0 0.00 1,024 -6.15 0.5721
2024-05-10 2024-03-31 13F MERCK COM 58933Y105 8,268 -1,000 -10.79 1,091 7.92 0.6049
2024-02-09 2023-12-31 13F MERCK COM 58933Y105 9,268 -950 -9.30 1,010 -3.90 0.6088
2023-11-13 2023-09-30 13F MERCK COM 58933Y105 10,218 -1,534 -13.05 1,052 -22.49 0.6752
2023-08-10 2023-06-30 13F MERCK COM 58933Y105 11,752 -200 -1.67 1,356 6.69 0.7738
2023-05-11 2023-03-31 13F MERCK COM 58933Y105 11,952 800 7.17 1,272 2.75 0.7383
2023-02-14 2022-12-31 13F MERCK COM 58933Y105 11,152 84 0.76 1,237 29.80 0.7256
2022-11-09 2022-09-30 13F MERCK COM 58933Y105 11,068 -2,265 -16.99 953 -21.63 0.5803
2022-08-11 2022-06-30 13F MERCK COM 58933Y105 13,333 10,440 360.87 1,216 413.08 0.6990
2022-05-12 2022-03-31 13F MERCK COM 58933Y105 2,893 -500 -14.74 237 -8.85 0.1193
2022-02-11 2021-12-31 13F MERCK COM 58933Y105 3,393 1,993 142.36 260 147.62 0.1241
2021-11-10 2021-09-30 13F MERCK COM 58933Y105 1,400 -400 -22.22 105 -25.00 0.0578
2021-08-12 2021-06-30 13F MERCK COM 58933Y105 1,800 -600 -25.00 140 -24.32 0.0750
2021-05-11 2021-03-31 13F MERCK & CO. COM 58933Y105 2,400 -9,965 -80.59 185 -81.70 0.1062
2021-02-11 2020-12-31 13F MERCK & CO. COM 58933Y105 12,365 775 6.69 1,011 5.20 0.5752
2020-11-12 2020-09-30 13F MERCK & CO. COM 58933Y105 11,590 -425 -3.54 961 3.44 0.5914
2020-08-10 2020-06-30 13F MERCK & CO. COM 58933Y105 12,015 -1,300 -9.76 929 -9.28 0.6026
2020-05-07 2020-03-31 13F MERCK & CO. COM 58933Y105 13,315 1,621 13.86 1,024 -3.76 0.7741
2020-02-10 2019-12-31 13F MERCK COM 58933Y105 11,694 1,721 17.26 1,064 26.82 0.6699
2019-11-12 2019-09-30 13F MERCK COM 58933Y105 9,973 3,272 48.83 839 49.29 0.5657
2019-08-12 2019-06-30 13F MERCK COM 58933Y105 6,701 1 0.01 562 0.90 0.3837
2019-05-10 2019-03-31 13F MERCK COM 58933Y105 6,700 5,700 570.00 557 632.89 0.4014
2019-02-11 2018-12-31 13F MERCK COM 58933Y105 1,000 600 150.00 76 171.43 0.0631
2018-11-13 2018-09-30 13F MERCK COM 58933Y105 400 -5 -1.23 28 12.00 0.0192
2018-08-09 2018-06-30 13F MERCK COM 58933Y105 405 5 1.25 25 13.64 0.0185
2018-05-08 2018-03-31 13F MERCK COM 58933Y105 400 -800 -66.67 22 -67.65 0.0153
2018-02-09 2017-12-31 13F MERCK COM 58933Y105 1,200 -3,850 -76.24 68 -78.95 0.0442
2017-11-09 2017-09-30 13F MERCK COM 58933Y105 5,050 300 6.32 323 6.25 0.2169
2017-08-08 2017-06-30 13F MERCK COM 58933Y105 4,750 949 24.97 304 26.14 0.2088
2017-05-08 2017-03-31 13F MERCK COM 58933Y105 3,801 1,201 46.19 241 57.52 0.1719
2017-02-07 2016-12-31 13F MERCK COM 58933Y105 2,600 1,600 160.00 153 146.77 0.1136
2016-11-07 2016-09-30 13F MERCK COM 58933Y105 1,000 1,000 0.00 62 0.0461
2016-02-09 2015-12-31 13F MERCK & CO INC COM 58933Y105 0 -15,741 -100.00 0 -100.00
2015-11-12 2015-09-30 13F MERCK & CO INC COM 58933Y105 15,741 -2,259 -12.55 777 -24.20 0.6812
2015-08-05 2015-06-30 13F MERCK & CO INC COM 58933Y105 18,000 3,606 25.05 1,025 23.94 0.8287
2015-05-12 2015-03-31 13F MERCK & CO INC COM 58933Y105 14,394 1,653 12.97 827 14.23 0.6897
2015-02-09 2014-12-31 13F MERCK & CO INC COM 58933Y105 12,741 4,701 58.47 724 51.78 0.6403
2014-11-12 2014-09-30 13F MERCK & CO INC COM 58933Y105 8,040 2 0.02 477 2.58 0.4216
2014-08-13 2014-06-30 13F MERCK & CO INC COM 58933Y105 8,038 -364 -4.33 465 -2.52 0.3975
2014-05-09 2014-03-31 13F MERCK & CO INC COM 58933Y105 8,402 8,402 477 0.4223
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.