Merck & Co., Inc.
MX ˙ BMV ˙ US58933Y1055
SecurityMX:MRK / Merck & Co., Inc.
InstitutionGreen Square Capital Advisors Llc
Latest Disclosed Ownership21,625 shares
Latest Disclosed Value $ 2,601,257
Green Square Capital Advisors Llc reports 1.37% decrease in ownership of MRK / Merck & Co., Inc.

On May 7, 2026 - Green Square Capital Advisors Llc filed a 13F-HR form disclosing ownership of 21,625 shares of Merck & Co., Inc. (MX:MRK) valued at $2,601,257 USD as of March 31, 2026. The entity filed a previous 13F-HR on February 9, 2026 disclosing 21,926 shares of Merck & Co., Inc.. This represents a change in shares of -1.37% 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 & CO INC COM Stock 58933Y105 21,625 -301 -1.37 2,601 12.74 0.2740
2026-02-09 2025-12-31 13F MERCK & CO INC COM Stock 58933Y105 21,926 -2,448 -10.04 2,308 19.60 0.2397
2025-11-14 2025-09-30 13F MERCK & CO INC COM Stock 58933Y105 24,374 0 0.00 1,929 0.00 0.2290
2025-07-30 2025-06-30 13F MERCK & CO INC COM Stock 58933Y105 24,374 21,146 655.08 1,929 567.47 0.2286
2025-04-21 2025-03-31 13F MERCK & CO INC COM Stock 58933Y105 3,228 -120 -3.58 290 -13.21 0.0439
2025-02-14 2024-12-31 13F MERCK & CO INC COM Stock 58933Y105 3,348 -2,595 -43.66 333 -50.67 0.0457
2024-11-07 2024-09-30 13F MERCK & CO INC COM Stock 58933Y105 5,943 -205 -3.33 676 -11.30 0.0949
2024-08-14 2024-06-30 13F MERCK & CO INC COM Stock 58933Y105 6,148 -17,768 -74.29 761 -75.88 0.1051
2024-05-15 2024-03-31 13F MERCK COM 58933Y105 23,916 790 3.42 3,156 25.15 0.4201
2024-01-18 2023-12-31 13F MERCK COM 58933Y105 23,126 -978 -4.06 2,521 1.61 0.3406
2023-10-10 2023-09-30 13F MERCK COM 58933Y105 24,104 -548 -2.22 2,481 -12.76 0.3315
2023-07-13 2023-06-30 13F MERCK COM 58933Y105 24,652 1,885 8.28 2,845 17.42 0.3578
2023-04-14 2023-03-31 13F MERCK COM 58933Y105 22,767 -2,798 -10.94 2,422 -14.60 0.3235
2023-02-15 2022-12-31 13F MERCK & CO INC COM Stock 58933Y105 25,565 212 0.84 2,836 29.91 0.4029
2022-10-31 2022-09-30 13F MERCK & CO INC COM Stock 58933Y105 25,353 -589 -2.27 2,183 -7.70 0.3874
2022-07-20 2022-06-30 13F MERCK & CO INC COM Stock 58933Y105 25,942 21,977 554.27 2,365 627.69 0.4327
2022-05-05 2022-03-31 13F MERCK & CO INC COM Stock 58933Y105 3,965 56 1.43 325 8.33 0.0510
2022-03-08 2021-12-31 13F MERCK & CO INC COM Stock 58933Y105 3,909 -282 -6.73 300 -4.76 0.0593
2021-10-19 2021-09-30 13F MERCK & CO INC COM Stock 58933Y105 4,191 1,088 35.06 315 30.71 0.0715
2021-07-29 2021-06-30 13F MERCK & CO INC COM Stock 58933Y105 3,103 326 11.74 241 12.62 0.0660
2021-05-17 2021-03-31 13F MERCK & CO. INC COM Stock 58933Y105 2,777 0 0.00 214 -5.73 0.0699
2021-02-16 2020-12-31 13F MERCK & CO. INC COM Stock 58933Y105 2,777 0 0.00 227 -1.30 0.0741
2020-11-16 2020-09-30 13F MERCK & CO. INC COM Stock 58933Y105 2,777 0 0.00 230 6.98 0.0936
2020-08-14 2020-06-30 13F MERCK & CO. INC COM Stock 58933Y105 2,777 2,777 215 0.0964
2020-05-15 2020-03-31 13F MERCK & CO INC COM Stock 58933Y105 0 -21,718 -100.00 0 -100.00
2020-02-14 2019-12-31 13F MERCK & CO INC COM Stock 58933Y105 21,718 748 3.57 1,975 11.90 1.1038
2019-11-14 2019-09-30 13F MERCK & CO INC COM Stock 58933Y105 20,970 -62 -0.29 1,765 0.06 1.0448
2019-08-14 2019-06-30 13F MERCK & CO INC COM Stock 58933Y105 21,032 -7,792 -27.03 1,764 -26.41 1.0970
2019-05-14 2019-03-31 13F MERCK & CO INC COM Stock 58933Y105 28,824 -94,240 -76.58 2,397 -74.69 1.5523
2019-02-14 2018-12-31 13F MERCK Stock 58933Y105 123,064 -15,201 -10.99 9,472 -4.08 1.3396
2018-11-14 2018-09-30 13F MERCK Stock 58933Y105 138,265 9,450 7.34 9,875 25.30 1.3797
2018-08-20 2018-06-30 13F MERCK Stock 58933Y105 128,815 -15,090 -10.49 7,881 -0.32 1.2648
2018-05-14 2018-03-31 13F MERCK Stock 58933Y105 143,905 15,850 12.38 7,906 8.70 1.2398
2018-02-22 2017-12-31 13F MERCK Stock 58933Y105 128,055 18,573 16.96 7,273 3.02 1.0948
2017-11-15 2017-09-30 13F MERCK Stock 58933Y105 109,482 7,377 7.22 7,060 7.39 1.2736
2017-08-14 2017-06-30 13F MERCK Stock 58933Y105 102,105 -1,290 -1.25 6,574 -0.66 1.1659
2017-05-17 2017-03-31 13F MERCK Stock 58933Y105 103,395 16,383 18.83 6,618 28.18 1.1675
2017-02-17 2016-12-31 13F MERCK Stock 58933Y105 87,012 3,844 4.62 5,163 -1.24 1.0329
2016-11-14 2016-09-30 13F MERCK Stock 58933Y105 83,168 5,796 7.49 5,228 16.33 1.1814
2016-07-25 2016-06-30 13F MERCK Stock 58933Y105 77,372 1,689 2.23 4,494 11.27 1.1073
2016-05-19 2016-03-31 13F MERCK Stock 58933Y105 75,683 38,507 103.58 4,039 103.89 1.0265
2016-02-10 2015-12-31 13F MERCK Stock 58933Y105 37,176 -45,093 -54.81 1,981 -51.69 0.4898
2015-11-12 2015-09-30 13F MERCK Stock 58933Y105 82,269 -15,710 -16.03 4,101 -27.02 1.0231
2015-08-12 2015-06-30 13F MERCK Stock 58933Y105 97,979 6,892 7.57 5,619 6.50 1.2491
2015-05-15 2015-03-31 13F MERCK Stock 58933Y105 91,087 91,087 5,276 1.1868
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.