Merck & Co., Inc.
MX ˙ BMV ˙ US58933Y1055
SecurityMX:MRK / Merck & Co., Inc.
InstitutionUSS Investment Management Ltd
Latest Disclosed Ownership434,031 shares
Latest Disclosed Value $ 52,213,929
USS Investment Management Ltd reports 2.60% increase in ownership of MRK / Merck & Co., Inc.

On April 24, 2026 - USS Investment Management Ltd filed a 13F-HR form disclosing ownership of 434,031 shares of Merck & Co., Inc. (MX:MRK) valued at $52,213,929 USD as of March 31, 2026. The entity filed a previous 13F-HR on February 13, 2026 disclosing 423,037 shares of Merck & Co., Inc.. This represents a change in shares of 2.60% 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.

Upgrade to unlock premium data and export to Excel .

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)
2026-04-24 2026-03-31 13F MERCK COM 58933Y105 434,031 10,994 2.60 52,214 17.24 0.2042
2026-02-13 2025-12-31 13F MERCK COM 58933Y105 423,037 279 0.07 44,535 25.54 0.2070
2025-11-13 2025-09-30 13F MERCK COM 58933Y105 422,758 0 0.00 35,476 6.08 0.1613
2025-08-14 2025-06-30 13F MERCK COM 58933Y105 422,758 5,036 1.21 33,442 -10.75 0.1982
2025-05-15 2025-03-31 13F MERCK COM 58933Y105 417,722 -192,358 -31.53 37,472 -38.27 0.2737
2025-02-14 2024-12-31 13F MERCK COM 58933Y105 610,080 187,064 44.22 60,700 26.35 0.4235
2024-11-13 2024-09-30 13F MERCK COM 58933Y105 423,016 -5,135 -1.20 48,040 -9.39 0.3500
2024-08-14 2024-06-30 13F MERCK COM 58933Y105 428,151 -153,605 -26.40 53,016 -30.92 0.4218
2024-05-15 2024-03-31 13F MERCK COM 58933Y105 581,756 10,968 1.92 76,742 23.31 0.6279
2024-02-14 2023-12-31 13F MERCK COM 58933Y105 570,788 -65,861 -10.34 62,233 -5.09 0.5543
2023-11-14 2023-09-30 13F MERCK COM 58933Y105 636,649 13,862 2.23 65,572 -8.72 0.7103
2023-08-14 2023-06-30 13F MERCK COM 58933Y105 622,787 -1,426 -0.23 71,832 8.19 0.8480
2023-05-15 2023-03-31 13F MERCK COM 58933Y105 624,213 12,650 2.07 66,394 -2.14 0.9031
2023-02-13 2022-12-31 13F MERCK COM 58933Y105 611,563 97,212 18.90 67,850 53.05 0.9500
2022-11-08 2022-09-30 13F MERCK COM 58933Y105 514,351 -186,868 -26.65 44,331 -30.81 0.6478
2022-08-12 2022-06-30 13F MERCK COM 58933Y105 701,219 -115,902 -14.18 64,067 -4.45 0.6398
2022-07-18 2022-03-31 13F/A-1 MERCK COM 58933Y105 817,121 28,802 3.65 67,049 10.97 0.5495
2022-05-13 2022-03-31 13F MERCK COM 58933Y105 817,121 28,802 67,049 0.5612
2022-02-14 2021-12-31 13F MERCK COM 58933Y105 788,319 0 0.00 60,421 2.05 0.4574
2021-11-15 2021-09-30 13F MERCK COM 58933Y105 788,319 -1,152,285 -59.38 59,207 -60.77 0.4996
2021-08-10 2021-06-30 13F MERCK COM 58933Y105 1,940,604 4,300 0.22 150,940 1.12 1.1935
2021-05-12 2021-03-31 13F MERCK & CO. COM 58933Y105 1,936,304 0 0.00 149,270 -5.73 1.2881
2021-02-12 2020-12-31 13F MERCK & CO. COM 58933Y105 1,936,304 15,700 0.82 158,341 -0.48 1.4373
2020-10-30 2020-09-30 13F MERCK & CO. COM 58933Y105 1,920,604 10,453 0.55 159,103 7.74 1.5336
2020-08-11 2020-06-30 13F MERCK & CO. COM 58933Y105 1,910,151 -213,187 -10.04 147,674 -9.67 1.5434
2020-05-11 2020-03-31 13F MERCK & CO. COM 58933Y105 2,123,338 -587,537 -21.67 163,476 -33.68 2.2234
2020-02-06 2019-12-31 13F MERCK COM 58933Y105 2,710,875 348,152 14.74 246,500 23.94 2.4033
2019-11-01 2019-09-30 13F MERCK COM 58933Y105 2,362,723 643,428 37.42 198,882 37.93 2.0565
2019-08-14 2019-06-30 13F/A-1 MERCK COM 58933Y105 1,719,295 0 0.00 144,189 0.87 1.4843
2019-07-19 2019-06-30 13F MERCK COM 58933Y105 1,719,295 0 144,189
2019-05-15 2019-03-31 13F/A-1 MERCK COM 58933Y105 1,719,295 64,945 3.93 142,951 13.00 1.6063
2019-04-05 2019-03-31 13F MERCK COM 58933Y105 1,719,295 64,945 142,951
2019-01-09 2018-12-31 13F MERCK COM 58933Y105 1,654,350 880,000 113.64 126,508 130.31 1.5593
2018-10-23 2018-09-30 13F MERCK COM 58933Y105 774,350 0 0.00 54,929 16.86 0.5528
2018-07-24 2018-06-30 13F MERCK COM 58933Y105 774,350 0 0.00 47,003 3.06 0.5133
2018-05-09 2018-03-31 13F MERCK COM 58933Y105 774,350 38,850 5.28 45,609 10.07 0.5060
2018-01-16 2017-12-31 13F MERCK COM 58933Y105 735,500 0 0.00 41,438 -12.00 0.4826
2017-12-06 2017-09-30 13F/A-1 MERCK COM 58933Y105 735,500 -30,500 -3.98 47,090 -4.09 0.3638
2017-11-13 2017-09-30 13F MERCK COM 58933Y105 735,500 -30,500 47,090
2017-12-06 2017-06-30 13F/A-1 MERCK COM 58933Y105 766,000 0 0.00 49,097 0.88 0.4583
2017-05-10 2017-03-31 13F MERCK COM 58933Y105 766,000 0 0.00 48,668 7.92 0.6728
2017-02-09 2016-12-31 13F MERCK COM 58933Y105 766,000 0 0.00 45,098 8.84 0.6910
2016-11-01 2016-09-30 13F MERCK COM 58933Y105 766,000 766,000 0.00 41,437 0.6369
2016-01-15 2015-12-31 13F MERCK COM 58933Y105 0 -262,200 -100.00 0 -100.00
2015-11-02 2015-09-30 13F MERCK COM 58933Y105 262,200 0 0.00 12,942 -13.30 0.2299
2015-07-16 2015-06-30 13F MERCK COM 58933Y105 262,200 -23,100 -8.10 14,927 -8.98 0.2368
2015-04-22 2015-03-31 13F MERCK COM 58933Y105 285,300 0 0.00 16,399 1.22 0.2679
2015-01-21 2014-12-31 13F MERCK COM 58933Y105 285,300 -1,780,300 -86.19 16,202 -82.25 0.2660
2013-10-24 2013-03-31 13F MERCK & CO INC COM 58933Y105 2,065,600 -257,211 -11.07 91,300 -3.99 1.9511
2013-10-24 2012-12-31 13F MERCK & CO INC COM 58933Y105 2,322,811 2,322,811 95,096 2.1709
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.