Merck & Co., Inc.
DE ˙ XTRA ˙ US58933Y1055
102,78 € ↑2,84 (2,84%)
2026-06-04
DEL PRIS
SecurityDE:6MK / Merck & Co., Inc.
InstitutionKlingenstein Fields & Co Lp
Latest Disclosed Ownership224,870 shares
Latest Disclosed Value $ 27,049,613
Klingenstein Fields & Co Lp reports 2.20% decrease in ownership of 6MK / Merck & Co., Inc.

On May 12, 2026 - Klingenstein Fields & Co Lp filed a 13F-HR form disclosing ownership of 224,870 shares of Merck & Co., Inc. (DE:6MK) valued at $23,431,454 USD as of March 31, 2026. The entity filed a previous 13F-HR on February 13, 2026 disclosing 229,918 shares of Merck & Co., Inc.. This represents a change in shares of -2.20% during the quarter. The current value of the position is $23,112,139 USD.

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)
2026-05-12 2026-03-31 13F MERCK COMMON 58933Y105 224,870 -5,048 -2.20 27,050 11.77 0.7935
2026-02-13 2025-12-31 13F MERCK COMMON 58933Y105 229,918 -2,403 -1.03 24,201 24.12 0.9078
2025-11-14 2025-09-30 13F MERCK COMMON 58933Y105 232,321 41 0.02 19,499 6.04 0.7363
2025-07-30 2025-06-30 13F MERCK COM 58933Y105 232,280 -51,041 -18.02 18,387 -27.70 0.7280
2025-04-28 2025-03-31 13F MERCK COM 58933Y105 283,321 2,465 0.88 25,431 -8.98 1.0813
2025-01-30 2024-12-31 13F MERCK COM 58933Y105 280,856 1,658 0.59 27,940 -11.88 1.1261
2024-10-29 2024-09-30 13F MERCK COM 58933Y105 279,198 -5,680 -1.99 31,706 -10.10 1.2604
2024-08-01 2024-06-30 13F MERCK COM 58933Y105 284,878 -19,597 -6.44 35,268 -12.22 1.4612
2024-04-29 2024-03-31 13F MERCK COM 58933Y105 304,475 -8,444 -2.70 40,175 17.77 1.6684
2024-02-01 2023-12-31 13F MERCK COM 58933Y105 312,919 -2,457 -0.78 34,114 5.07 1.5207
2023-10-27 2023-09-30 13F MERCK COM 58933Y105 315,376 -618 -0.20 32,468 -10.96 1.5854
2023-08-01 2023-06-30 13F MERCK COM 58933Y105 315,994 -3,684 -1.15 36,463 7.21 1.6852
2023-04-28 2023-03-31 13F MERCK COM 58933Y105 319,678 -3,874 -1.20 34,011 -5.26 1.7025
2023-02-02 2022-12-31 13F MERCK COM 58933Y105 323,552 -7,702 -2.33 35,898 25.83 1.8636
2022-10-28 2022-09-30 13F MERCK COM 58933Y105 331,254 222 0.07 28,528 -5.47 1.5688
2022-08-01 2022-06-30 13F MERCK COM 58933Y105 331,032 34 0.01 30,180 11.13 1.5694
2022-04-27 2022-03-31 13F MERCK COM 58933Y105 330,998 2,342 0.71 27,158 7.82 1.1632
2022-01-31 2021-12-31 13F MERCK COM 58933Y105 328,656 -5,666 -1.69 25,188 0.31 1.0122
2021-10-26 2021-09-30 13F MERCK COM 58933Y105 334,322 580 0.17 25,111 -3.26 1.0710
2021-07-26 2021-06-30 13F MERCK COM 58933Y105 333,742 3,215 0.97 25,956 1.87 1.0738
2021-04-29 2021-03-31 13F MERCK & CO. COM 58933Y105 330,527 1,972 0.60 25,480 -5.19 1.1520
2021-02-02 2020-12-31 13F MERCK & CO. COM 58933Y105 328,555 1,211 0.37 26,875 -1.02 1.2183
2020-10-30 2020-09-30 13F MERCK & CO. COM 58933Y105 327,344 -2,536 -0.77 27,153 6.44 1.3556
2020-08-03 2020-06-30 13F MERCK & CO. COM 58933Y105 329,880 -884 -0.27 25,510 0.24 1.3937
2020-05-07 2020-03-31 13F MERCK & CO. COM 58933Y105 330,764 -556 -0.17 25,449 -15.54 1.6582
2020-02-04 2019-12-31 13F MERCK COM 58933Y105 331,320 -7,266 -2.15 30,133 5.72 1.5161
2019-11-01 2019-09-30 13F MERCK COM 58933Y105 338,586 -5,437 -1.58 28,502 -1.19 1.5047
2019-08-12 2019-06-30 13F MERCK COM 58933Y105 344,023 -8,900 -2.52 28,846 -1.73 1.4973
2019-04-29 2019-03-31 13F MERCK COM 58933Y105 352,923 -111,500 -24.01 29,353 -17.28 1.5771
2019-01-22 2018-12-31 13F Merck & COM 58933Y105 464,423 -11,822 -2.48 35,486 5.03 1.5055
2018-11-01 2018-09-30 13F Merck & COM 58933Y105 476,245 15,765 3.42 33,785 20.87 1.2102
2018-07-26 2018-06-30 13F Merck & COM 58933Y105 460,480 15,383 3.46 27,951 15.29 1.0654
2018-05-01 2018-03-31 13F Merck & COM 58933Y105 445,097 646 0.15 24,244 -3.06 0.9272
2018-01-30 2017-12-31 13F Merck & COM 58933Y105 444,451 2,530 0.57 25,009 -11.62 0.9203
2017-11-01 2017-09-30 13F Merck & COM 58933Y105 441,921 -6,659 -1.48 28,296 -1.58 1.0889
2017-07-27 2017-06-30 13F Merck & COM 58933Y105 448,580 2,130 0.48 28,749 1.34 1.1272
2017-05-01 2017-03-31 13F Merck & COM 58933Y105 446,450 22,958 5.42 28,368 13.79 1.1518
2017-01-26 2016-12-31 13F Merck & COM 58933Y105 423,492 4,578 1.09 24,931 -4.64 1.0890
2016-11-02 2016-09-30 13F Merck & COM 58933Y105 418,914 -1,828 -0.43 26,145 7.86 1.2030
2016-08-01 2016-06-30 13F Merck & COM 58933Y105 420,742 283,083 205.64 24,239 232.82 1.1329
2016-05-02 2016-03-31 13F Merck & COM 58933Y105 137,659 44,913 48.43 7,283 48.66 0.3642
2016-02-01 2015-12-31 13F Merck COM 58933Y105 92,746 34,800 60.06 4,899 71.17 0.2428
2015-10-23 2015-09-30 13F Merck COM 58933Y105 57,946 14,100 32.16 2,862 14.66 0.1416
2015-08-03 2015-06-30 13F Merck COM 58933Y105 43,846 -3,460 -7.31 2,496 -8.20 0.1115
2015-05-05 2015-03-31 13F Merck COM 58933Y105 47,306 47,306 0.00 2,719 0.1204
2015-02-04 2014-12-31 13F Merck COM 58933Y105 0 -48,681 -100.00 0 -100.00
2014-10-21 2014-09-30 13F Merck COM 58933Y105 48,681 0 0.00 2,886 2.49 0.1258
2014-07-24 2014-06-30 13F Merck COM 58933Y105 48,681 -8,104 -14.27 2,816 -12.66 0.1197
2014-05-02 2014-03-31 13F Merck COM 58933Y105 56,785 -106,560 -65.24 3,224 -60.56 0.1446
2014-02-05 2013-12-31 13F Merck COM 58933Y105 163,345 -3,933 -2.35 8,175 2.65 0.2925
2013-11-04 2013-09-30 13F Merck COM 58933Y105 167,278 -52,705 -23.96 7,964 -22.06 0.3117
2013-08-08 2013-06-30 13F Merck COM 58933Y105 219,983 219,983 10,218 0.3657
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.