Merck & Co., Inc.
MX ˙ BMV ˙ US58933Y1055
SecurityMX:MRK / Merck & Co., Inc.
InstitutionShelton Capital Management
Latest Disclosed Ownership255,813 shares
Latest Disclosed Value $ 30,771,737
Shelton Capital Management reports 8.54% decrease in ownership of MRK / Merck & Co., Inc.

On May 15, 2026 - Shelton Capital Management filed a 13F-HR form disclosing ownership of 255,813 shares of Merck & Co., Inc. (MX:MRK) valued at $30,771,737 USD as of March 31, 2026. The entity filed a previous 13F-HR on February 17, 2026 disclosing 279,686 shares of Merck & Co., Inc.. This represents a change in shares of -8.54% 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)
2026-05-15 2026-03-31 13F MERCK COM 58933Y105 255,813 -23,873 -8.54 30,772 4.52 0.6731
2026-02-17 2025-12-31 13F MERCK COM 58933Y105 279,686 91,910 48.95 29,440 86.80 0.5811
2025-11-14 2025-09-30 13F MERCK COM 58933Y105 187,776 9,724 5.46 15,760 11.82 0.3375
2025-08-13 2025-06-30 13F MERCK COM 58933Y105 178,052 22,024 14.12 14,095 0.64 0.3242
2025-05-15 2025-03-31 13F MERCK COM 58933Y105 156,028 21,557 16.03 14,005 4.69 0.3336
2025-02-13 2024-12-31 13F MERCK COM 58933Y105 134,471 -9,267 -6.45 13,377 -18.04 0.3329
2024-11-14 2024-09-30 13F MERCK COM 58933Y105 143,738 28,030 24.22 16,323 13.95 0.4190
2024-08-13 2024-06-30 13F MERCK COM 58933Y105 115,708 19,686 20.50 14,325 13.05 0.3889
2024-05-15 2024-03-31 13F MERCK COM 58933Y105 96,022 -39,708 -29.26 12,670 -14.37 0.3598
2024-02-14 2023-12-31 13F MERCK COM 58933Y105 135,730 30,038 28.42 14,797 35.99 0.4684
2023-11-14 2023-09-30 13F MERCK COM 58933Y105 105,692 24,200 29.70 10,881 15.72 0.3986
2023-08-10 2023-06-30 13F MERCK COM 58933Y105 81,492 34,281 72.61 9,403 87.24 0.3376
2023-05-11 2023-03-31 13F MERCK COM 58933Y105 47,211 36,211 329.19 5,023 311.64 0.2092
2023-02-13 2022-12-31 13F MERCK COM 58933Y105 11,000 -180,815 -94.27 1,220 -92.61 0.1278
2022-11-14 2022-09-30 13F MERCK COM 58933Y105 191,815 15,704 8.92 16,519 2.88 0.7854
2022-08-11 2022-06-30 13F MERCK COM 58933Y105 176,111 -32,296 -15.50 16,056 -6.11 0.7221
2022-05-12 2022-03-31 13F MERCK COM 58933Y105 208,407 37,189 21.72 17,100 30.32 0.6314
2022-02-11 2021-12-31 13F MERCK COM 58933Y105 171,218 82,244 92.44 13,122 96.35 0.4644
2021-11-15 2021-09-30 13F MERCK COM 58933Y105 88,974 -6,079 -6.40 6,683 -9.59 0.2611
2021-08-12 2021-06-30 13F MERCK COM 58933Y105 95,053 -18,199 -16.07 7,392 -15.34 0.2790
2021-05-14 2021-03-31 13F MERCK & CO. COM 58933Y105 113,252 6,136 5.73 8,731 -0.35 0.3039
2021-02-16 2020-12-31 13F MERCK & CO. COM 58933Y105 107,116 29,900 38.72 8,762 36.80 0.3937
2020-11-09 2020-09-30 13F MERCK & CO. COM 58933Y105 77,216 13,173 20.57 6,405 29.34 0.2651
2020-08-12 2020-06-30 13F MERCK & CO. COM 58933Y105 64,043 29,300 84.33 4,952 85.26 0.2728
2020-05-13 2020-03-31 13F MERCK & CO. COM 58933Y105 34,743 -19,697 -36.18 2,673 -46.01 0.1937
2020-02-11 2019-12-31 13F MERCK COM 58933Y105 54,440 -4,761 -8.04 4,951 -0.66 0.2736
2019-11-13 2019-09-30 13F MERCK COM 58933Y105 59,201 -82 -0.14 4,984 0.26 0.2942
2019-08-14 2019-06-30 13F MERCK COM 58933Y105 59,283 54,272 1,083.06 4,971 -91.75 0.2864
2019-05-10 2019-03-31 13F MERCK COM 58933Y105 5,011 -29,637 -85.54 60,248 2,176.09 0.2376
2019-01-31 2018-12-31 13F MERCK COM 58933Y105 34,648 -300 -0.86 2,647 6.78 0.1800
2018-11-14 2018-09-30 13F MERCK COM 58933Y105 34,948 -11,235 -24.33 2,479 -11.56 0.1414
2018-08-10 2018-06-30 13F MERCK COM 58933Y105 46,183 -6,465 -12.28 2,803 -2.27 0.1743
2018-05-15 2018-03-31 13F MERCK COM 58933Y105 52,648 -162 -0.31 2,868 -3.50 0.1881
2018-02-06 2017-12-31 13F MERCK COM 58933Y105 52,810 0 0.00 2,972 -12.10 0.1908
2017-11-28 2017-09-30 13F/A-1 MERCK COM 58933Y105 52,810 0 0.00 3,381 -0.12 0.2282
2017-11-14 2017-09-30 13F MERCK COM 58933Y105 52,810 0 3,381
2017-08-14 2017-06-30 13F MERCK COM 58933Y105 52,810 -803 -1.50 3,385 -0.65 0.2392
2017-11-28 2017-03-31 13F/A-1 MERCK COM 58933Y105 53,613 -8,800 -14.10 3,407 -7.27 0.2359
2017-05-15 2017-03-31 13F MERCK COM 58933Y105 57,515 -4,898 3,654
2017-11-28 2016-12-31 13F/A-2 MERCK COM 58933Y105 62,413 759 1.23 3,674 -4.52 0.2797
2017-02-16 2016-12-31 13F/A-1 MERCK COM 58933Y105 62,413 0 3,674 0.3225
2017-02-13 2016-12-31 13F MERCK COM 58933Y105 62,413 3,674
2017-12-06 2016-09-30 13F/A-2 MERCK COM 58933Y105 61,654 -5,824 -8.63 3,848 -1.00 0.3212
2017-12-04 2016-09-30 13F/A-1 MERCK COM 58933Y105 62,413 759 3,674 0.2341
2016-11-14 2016-09-30 13F MERCK COM 58933Y105 61,654 -5,824 3,848
2016-08-01 2016-06-30 13F MERCK COM 58933Y105 67,478 8,461 14.34 3,887 24.46 0.3425
2016-05-13 2016-03-31 13F MERCK & CO INC COM 58933Y105 59,017 -4,400 -6.94 3,123 -6.78 0.2827
2016-02-01 2015-12-31 13F MERCK & CO INC COM 58933Y105 63,417 609 0.97 3,350 7.99 0.3239
2015-11-02 2015-09-30 13F MERCK & CO INC COM 58933Y105 62,808 1,300 2.11 3,102 -11.42 0.3415
2015-08-11 2015-06-30 13F MERCK & CO INC COM 58933Y105 61,508 4,982 8.81 3,502 7.79 0.3622
2015-05-12 2015-03-31 13F MERCK & CO INC COM 58933Y105 56,526 2,700 5.02 3,249 6.28 0.3510
2015-02-10 2014-12-31 13F MERCK & CO INC COM 58933Y105 53,826 610 1.15 3,057 -3.11 0.3561
2014-10-15 2014-09-30 13F MERCK & CO INC COM 58933Y105 53,216 -1,800 -3.27 3,155 -0.88 0.4241
2014-07-25 2014-06-30 13F MERCK & CO INC COM 58933Y105 55,016 -5,643 -9.30 3,183 -7.58 0.4444
2014-04-14 2014-03-31 13F MERCK & CO INC COM 58933Y105 60,659 3,900 6.87 3,444 21.22 0.5049
2014-01-22 2013-12-31 13F MERCK & CO INC COM 58933Y105 56,759 0 0.00 2,841 5.14 0.4296
2013-10-16 2013-09-30 13F MERCK & CO INC COM 58933Y105 56,759 0 0.00 2,702 2.50 0.4521
2013-07-10 2013-06-30 13F MERCK & CO INC COM 58933Y105 56,759 56,759 2,636 0.4809
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.