Merck & Co., Inc.
MX ˙ BMV ˙ US58933Y1055
SecurityMX:MRK / Merck & Co., Inc.
InstitutionGabelli Funds Llc
Latest Disclosed Ownership288,480 shares
Latest Disclosed Value $ 34,701,259
Gabelli Funds Llc reports 5.13% decrease in ownership of MRK / Merck & Co., Inc.

On May 14, 2026 - Gabelli Funds Llc filed a 13F-HR form disclosing ownership of 288,480 shares of Merck & Co., Inc. (MX:MRK) valued at $34,701,259 USD as of March 31, 2026. The entity filed a previous 13F-HR on February 5, 2026 disclosing 304,065 shares of Merck & Co., Inc.. This represents a change in shares of -5.13% 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)
2026-05-14 2026-03-31 13F MERCK EQUITY 58933Y105 288,480 -15,585 -5.13 34,701 8.42 0.2344
2026-02-05 2025-12-31 13F MERCK EQUITY 58933Y105 304,065 -21,375 -6.57 32,006 17.17 0.2167
2025-11-12 2025-09-30 13F MERCK EQUITY 58933Y105 325,440 -675 -0.21 27,314 5.81 0.1849
2025-08-13 2025-06-30 13F MERCK EQUITY 58933Y105 326,115 -23,500 -6.72 25,815 -17.74 0.1833
2025-05-14 2025-03-31 13F MERCK EQUITY 58933Y105 349,615 -4,590 -1.30 31,381 -10.94 0.2392
2025-02-13 2024-12-31 13F MERCK EQUITY 58933Y105 354,205 19,084 5.69 35,236 -7.41 0.2646
2024-11-13 2024-09-30 13F MERCK EQUITY 58933Y105 335,121 17,155 5.40 38,056 -3.32 0.2743
2024-08-13 2024-06-30 13F MERCK EQUITY 58933Y105 317,966 12,705 4.16 39,364 -2.27 0.2990
2024-05-14 2024-03-31 13F MERCK EQUITY 58933Y105 305,261 -7,015 -2.25 40,279 18.31 0.2967
2024-02-13 2023-12-31 13F MERCK EQUITY 58933Y105 312,276 -16,475 -5.01 34,044 0.59 0.2622
2023-11-08 2023-09-30 13F MERCK EQUITY 58933Y105 328,751 -11,920 -3.50 33,845 -13.90 0.2746
2023-08-10 2023-06-30 13F MERCK EQUITY 58933Y105 340,671 -16,540 -4.63 39,310 3.44 0.2979
2023-05-12 2023-03-31 13F MERCK EQUITY 58933Y105 357,211 -15,440 -4.14 38,004 -8.08 0.2880
2023-02-13 2022-12-31 13F MERCK EQUITY 58933Y105 372,651 -14,525 -3.75 41,346 24.00 0.3213
2022-11-14 2022-09-30 13F/A-1 MERCK COM 58933Y105 387,176 -15,350 -3.81 33,344 -9.14 0.2749
2022-11-10 2022-09-30 13F MERCK COM 58933Y105 387,176 -15,350 33,344 0.2749
2022-08-12 2022-06-30 13F MERCK COM 58933Y105 402,526 -38,100 -8.65 36,698 1.51 0.2818
2022-05-18 2022-03-31 13F/A-1 MERCK COM 58933Y105 440,626 -17,975 -3.92 36,153 2.86 0.2375
2022-05-13 2022-03-31 13F MERCK COM 58933Y105 440,626 -17,975 36,153 0.2441
2022-02-11 2021-12-31 13F MERCK COM 58933Y105 458,601 -46,089 -9.13 35,147 -7.28 0.2218
2021-11-12 2021-09-30 13F MERCK COM 58933Y105 504,690 4,520 0.90 37,907 -2.55 0.2511
2021-08-13 2021-06-30 13F MERCK COM 58933Y105 500,170 700 0.14 38,898 1.02 0.2477
2021-05-14 2021-03-31 13F MERCK COM 58933Y105 499,470 -11,320 -2.22 38,504 -7.85 0.2581
2021-02-05 2020-12-31 13F MERCK COM 58933Y105 510,790 45,900 9.87 41,783 8.35 0.2976
2020-11-06 2020-09-30 13F MERCK COM 58933Y105 464,890 10,810 2.38 38,563 9.82 0.3004
2020-08-13 2020-06-30 13F MERCK COM 58933Y105 454,080 -192,800 -29.80 35,114 -29.45 0.2861
2020-05-14 2020-03-31 13F MERCK COM 58933Y105 646,880 -37,250 -5.44 49,771 -20.01 0.4434
2020-02-14 2019-12-31 13F MERCK COM 58933Y105 684,130 114,400 20.08 62,222 29.74 0.4025
2019-11-01 2019-09-30 13F MERCK COM 58933Y105 569,730 -27,300 -4.57 47,960 -4.20 0.3168
2019-08-02 2019-06-30 13F MERCK COM 58933Y105 597,030 -19,500 -3.16 50,061 -2.37 0.3214
2019-05-02 2019-03-31 13F MERCK COM 58933Y105 616,530 -77,000 -11.10 51,277 -3.24 0.3224
2019-01-30 2018-12-31 13F MERCK COM 58933Y105 693,530 -93,500 -11.88 52,993 -5.08 0.3633
2018-11-02 2018-09-30 13F MERCK COM 58933Y105 787,030 -4,900 -0.62 55,832 16.15 0.3203
2018-08-10 2018-06-30 13F MERCK COM 58933Y105 791,930 2,700 0.34 48,070 11.82 0.2847
2018-05-09 2018-03-31 13F MERCK COM 58933Y105 789,230 -16,000 -1.99 42,989 -5.12 0.2564
2018-02-02 2017-12-31 13F MERCK COM 58933Y105 805,230 -144,821 -15.24 45,310 -25.52 0.2610
2017-11-01 2017-09-30 13F MERCK COM 58933Y105 950,051 95,000 11.11 60,832 11.01 0.3485
2017-08-03 2017-06-30 13F MERCK COM 58933Y105 855,051 -15,300 -1.76 54,800 -0.91 0.3256
2017-05-04 2017-03-31 13F MERCK COM 58933Y105 870,351 -44,950 -4.91 55,302 2.63 0.3260
2017-02-10 2016-12-31 13F MERCK COM 58933Y105 915,301 -110,500 -10.77 53,884 -15.83 0.3189
2016-11-10 2016-09-30 13F MERCK COM 58933Y105 1,025,801 -32,500 -3.07 64,020 5.00 0.3799
2016-08-04 2016-06-30 13F MERCK COM 58933Y105 1,058,301 -9,500 -0.89 60,969 7.92 0.3597
2016-05-05 2016-03-31 13F MERCK COM 58933Y105 1,067,801 -78,100 -6.82 56,497 -6.66 0.3407
2016-02-05 2015-12-31 13F MERCK COM 58933Y105 1,145,901 15,651 1.38 60,526 8.42 0.3664
2015-10-23 2015-09-30 13F MERCK COM 58933Y105 1,130,250 -1,500 -0.13 55,823 -13.36 0.3318
2015-08-05 2015-06-30 13F MERCK COM 58933Y105 1,131,750 -13,100 -1.14 64,431 -2.09 0.3373
2015-05-01 2015-03-31 13F MERCK COM 58933Y105 1,144,850 47,200 4.30 65,806 5.57 0.3339
2015-02-05 2014-12-31 13F MERCK COM 58933Y105 1,097,650 2,000 0.18 62,336 -4.02 0.3031
2014-10-30 2014-09-30 13F MERCK COM 58933Y105 1,095,650 37,500 3.54 64,950 6.10 0.3297
2014-08-06 2014-06-30 13F MERCK COM 58933Y105 1,058,150 -58,800 -5.26 61,214 -3.46 0.3026
2014-05-16 2014-03-31 13F/A-1 MERCK COM 58933Y105 1,116,950 3,000 0.27 63,409 13.73 0.3292
2014-05-02 2014-03-31 13F MERCK COM 58933Y105 1,116,950 63,409
2014-02-07 2013-12-31 13F MERCK COM 58933Y105 1,113,950 6,500 0.59 55,753 5.74 0.2969
2013-11-07 2013-09-30 13F MERCK COM 58933Y105 1,107,450 -10,500 -0.94 52,725 1.53 0.3002
2013-08-02 2013-06-30 13F/A-1 MERCK COM 58933Y105 1,117,950 1,117,950 51,929 0.3151
2013-08-01 2013-06-30 13F MERCK COM 58933Y105 1,117,950 51,929 0.3151
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.