Merck & Co., Inc.
MX ˙ BMV ˙ US58933Y1055
SecurityMX:MRK / Merck & Co., Inc.
InstitutionTexas Yale Capital Corp.
Latest Disclosed Ownership58,188 shares
Latest Disclosed Value $ 6,999,435
Texas Yale Capital Corp. reports 0.66% increase in ownership of MRK / Merck & Co., Inc.

On May 4, 2026 - Texas Yale Capital Corp. filed a 13F-HR form disclosing ownership of 58,188 shares of Merck & Co., Inc. (MX:MRK) valued at $6,999,435 USD as of March 31, 2026. The entity filed a previous 13F-HR on February 10, 2026 disclosing 57,808 shares of Merck & Co., Inc.. This represents a change in shares of 0.66% 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)
2026-05-04 2026-03-31 13F MERCK COM 58933Y105 58,188 380 0.66 6,999 15.04 0.1986
2026-02-10 2025-12-31 13F MERCK COM 58933Y105 57,808 325 0.57 6,085 26.12 0.1845
2025-11-07 2025-09-30 13F MERCK COM 58933Y105 57,483 19,600 51.74 4,825 60.91 0.1518
2025-08-06 2025-06-30 13F MERCK COM 58933Y105 37,883 835 2.25 2,999 -9.83 0.0982
2025-05-07 2025-03-31 13F MERCK COM 58933Y105 37,048 -3,640 -8.95 3,325 -17.84 0.1365
2025-02-13 2024-12-31 13F MERCK COM 58933Y105 40,688 750 1.88 4,048 -10.76 0.1628
2024-11-12 2024-09-30 13F MERCK COM 58933Y105 39,938 -435 -1.08 4,535 -9.26 0.1970
2024-08-13 2024-06-30 13F MERCK COM 58933Y105 40,373 465 1.17 4,998 -5.07 0.2380
2024-05-08 2024-03-31 13F MERCK COM 58933Y105 39,908 0 0.00 5,266 21.03 0.2338
2024-02-13 2023-12-31 13F MERCK COM 58933Y105 39,908 0 0.00 4,351 5.89 0.2072
2023-11-09 2023-09-30 13F MERCK COM 58933Y105 39,908 -200 -0.50 4,109 -11.24 0.1852
2023-08-03 2023-06-30 13F MERCK COM 58933Y105 40,108 0 0.00 4,628 8.46 0.2177
2023-05-10 2023-03-31 13F MERCK COM 58933Y105 40,108 0 0.00 4,267 -4.09 0.2169
2023-02-13 2022-12-31 13F MERCK COM 58933Y105 40,108 -2,300 -5.42 4,450 21.82 0.2538
2022-11-08 2022-09-30 13F MERCK COM 58933Y105 42,408 1,035 2.50 3,652 -3.18 0.2340
2022-08-11 2022-06-30 13F MERCK COM 58933Y105 41,373 820 2.02 3,772 13.38 0.2438
2022-05-10 2022-03-31 13F MERCK COM 58933Y105 40,553 0 0.00 3,327 7.05 0.1813
2022-02-10 2021-12-31 13F MERCK COM 58933Y105 40,553 742 1.86 3,108 3.95 0.1580
2021-11-08 2021-09-30 13F MERCK COM 58933Y105 39,811 20 0.05 2,990 -3.39 0.1695
2021-08-05 2021-06-30 13F MERCK COM 58933Y105 39,791 341 0.86 3,095 1.78 0.1768
2021-05-12 2021-03-31 13F MERCK & CO. COM 58933Y105 39,450 -6,900 -14.89 3,041 -19.78 0.1910
2021-02-10 2020-12-31 13F MERCK & CO. COM 58933Y105 46,350 40 0.09 3,791 -1.30 0.2547
2020-11-10 2020-09-30 13F MERCK & CO. COM 58933Y105 46,310 0 0.00 3,841 7.26 0.2946
2020-07-31 2020-06-30 13F MERCK & CO. COM 58933Y105 46,310 -487 -1.04 3,581 -0.56 0.2913
2020-05-13 2020-03-31 13F MERCK & CO. COM 58933Y105 46,797 7,821 20.07 3,601 1.58 0.3542
2020-02-11 2019-12-31 13F MERCK COM 58933Y105 38,976 33 0.08 3,545 8.15 0.2430
2019-10-31 2019-09-30 13F MERCK COM 58933Y105 38,943 0 0.00 3,278 0.40 0.2351
2019-07-24 2019-06-30 13F MERCK COM 58933Y105 38,943 -37,335 -48.95 3,265 -48.53 0.2435
2019-05-10 2019-03-31 13F MERCK COM 58933Y105 76,278 39,274 106.13 6,344 124.41 0.2537
2019-02-11 2018-12-31 13F MERCK COM 58933Y105 37,004 1,334 3.74 2,827 11.74 0.2552
2018-11-13 2018-09-30 13F MERCK COM 58933Y105 35,670 0 0.00 2,530 16.86 0.2044
2018-08-07 2018-06-30 13F MERCK COM 58933Y105 35,670 -1,538 -4.13 2,165 6.81 0.1859
2018-05-03 2018-03-31 13F MERCK COM 58933Y105 37,208 1,700 4.79 2,027 1.45 0.1745
2018-02-07 2017-12-31 13F MERCK COM 58933Y105 35,508 -11,690 -24.77 1,998 -33.88 0.1720
2017-11-08 2017-09-30 13F MERCK COM 58933Y105 47,198 -1,072 -2.22 3,022 -2.33 0.2609
2017-08-03 2017-06-30 13F MERCK COM 58933Y105 48,270 0 0.00 3,094 0.88 0.2719
2017-05-03 2017-03-31 13F MERCK COM 58933Y105 48,270 1,575 3.37 3,067 11.57 0.2704
2017-02-13 2016-12-31 13F MERCK COM 58933Y105 46,695 15,730 50.80 2,749 42.21 0.2598
2016-11-14 2016-09-30 13F MERCK COM 58933Y105 30,965 0 0.00 1,933 8.35 0.1858
2016-08-12 2016-06-30 13F MERCK COM 58933Y105 30,965 -100 -0.32 1,784 8.52 0.1773
2016-05-13 2016-03-31 13F MERCK & CO INC COM 58933Y105 31,065 0 0.00 1,644 0.18 0.1692
2016-05-10 2015-12-31 13F/A-1 MERCK & CO INC COM 58933Y105 31,065 -950 -2.97 1,641 3.80 0.1476
2016-02-05 2015-12-31 13F MERCK & CO INC COM 58933Y105 31,065 1,641
2016-05-10 2015-09-30 13F/A-1 MERCK & CO INC COM 58933Y105 32,015 0 0.00 1,581 -13.27 0.1445
2015-11-10 2015-09-30 13F MERCK & CO INC COM 58933Y105 32,015 1,581
2016-05-10 2015-06-30 13F/A-1 MERCK & CO INC COM 58933Y105 32,015 0 0.00 1,823 -0.92 0.1509
2015-07-30 2015-06-30 13F MERCK & CO INC COM 58933Y105 32,015 1,823
2016-05-10 2015-03-31 13F/A-1 MERCK & CO INC COM 58933Y105 32,015 -1,102 -3.33 1,840 -2.18 0.1465
2015-04-16 2015-03-31 13F MERCK & CO INC COM 58933Y105 32,015 1,840
2015-02-12 2014-12-31 13F MERCK & CO INC COM 58933Y105 33,117 0 0.00 1,881 -4.18 0.1628
2014-12-01 2014-09-30 13F/A-1 MERCK & CO INC COM 58933Y105 33,117 3,567 12.07 1,963 14.86 0.1846
2014-11-13 2014-09-30 13F MERCK & CO INC COM 58933Y105 33,117 1,963
2014-08-12 2014-06-30 13F MERCK & CO INC COM 58933Y105 29,550 0 0.00 1,709 1.85 0.2142
2014-08-04 2014-03-31 13F/A-1 MERCK & CO INC COM 58933Y105 29,550 10,400 54.31 1,678 75.16 0.2331
2014-05-15 2014-03-31 13F MERCK & CO INC COM 58933Y105 29,550 1,678
2014-02-11 2013-12-31 13F MERCK & CO INC COM 58933Y105 19,150 0 0.00 958 5.04 0.1470
2013-11-05 2013-09-30 13F MERCK & CO INC COM 58933Y105 19,150 400 2.13 912 4.71 0.1539
2013-08-07 2013-06-30 13F MERCK & CO INC COM 58933Y105 18,750 18,750 871 0.1519
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.