Merck & Co., Inc.
BG ˙ BUL ˙ US58933Y1055
SecurityBG:6MK / Merck & Co., Inc.
InstitutionGladstone Institutional Advisory LLC
Latest Disclosed Ownership84,536 shares
Latest Disclosed Value $ 10,168,921
Gladstone Institutional Advisory LLC reports 2.06% increase in ownership of 6MK / Merck & Co., Inc.

On May 14, 2026 - Gladstone Institutional Advisory LLC filed a 13F-HR form disclosing ownership of 84,536 shares of Merck & Co., Inc. (BG:6MK) valued at $10,168,921 USD as of March 31, 2026. The entity filed a previous 13F-HR on February 17, 2026 disclosing 82,826 shares of Merck & Co., Inc.. This represents a change in shares of 2.06% 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 COM 58933Y105 84,536 1,710 2.06 10,169 16.63 0.3768
2026-02-17 2025-12-31 13F MERCK COM 58933Y105 82,826 -1,574 -1.86 8,718 23.08 0.3292
2025-10-22 2025-09-30 13F MERCK COM 58933Y105 84,400 -172 -0.20 7,084 5.81 0.2728
2025-08-12 2025-06-30 13F MERCK COM 58933Y105 84,572 -489 -0.57 6,695 -12.32 0.2766
2025-05-15 2025-03-31 13F MERCK COM 58933Y105 85,061 6,263 7.95 7,635 -2.59 0.3559
2025-01-29 2024-12-31 13F MERCK COM 58933Y105 78,798 -2,053 -2.54 7,839 -14.63 0.3636
2024-10-28 2024-09-30 13F MERCK COM 58933Y105 80,851 6,793 9.17 9,181 0.14 0.4483
2024-08-02 2024-06-30 13F MERCK COM 58933Y105 74,058 -1,074 -1.43 9,168 -7.52 0.4774
2024-05-14 2024-03-31 13F MERCK COM 58933Y105 75,132 -19,510 -20.61 9,914 -3.92 0.5439
2024-02-09 2023-12-31 13F MERCK COM 58933Y105 94,642 18,679 24.59 10,318 31.93 0.5787
2023-11-13 2023-09-30 13F MERCK COM 58933Y105 75,963 4,883 6.87 7,820 -4.65 0.5064
2023-08-10 2023-06-30 13F MERCK COM 58933Y105 71,080 12,702 21.76 8,202 32.06 0.5000
2023-05-12 2023-03-31 13F MERCK COM 58933Y105 58,378 -38,699 -39.86 6,211 -42.34 0.4022
2023-02-01 2022-12-31 13F MERCK COM 58933Y105 97,077 42,544 78.02 10,771 129.34 0.7601
2023-01-30 2022-09-30 13F/A-1 MERCK COM 58933Y105 54,533 2,885 5.59 4,696 -0.28 0.3671
2022-10-20 2022-09-30 13F MERCK COM 58933Y105 54,533 2,885 4,696 0.3671
2023-01-30 2022-06-30 13F/A-1 MERCK COM 58933Y105 51,648 -864 -1.65 4,709 9.28 0.3724
2022-08-15 2022-06-30 13F MERCK COM 58933Y105 51,648 -864 4,709 0.3724
2023-01-30 2022-03-31 13F/A-1 MERCK COM 58933Y105 52,512 2,523 5.05 4,309 12.48 0.2913
2022-05-04 2022-03-31 13F MERCK COM 58933Y105 52,512 2,523 4,309 0.2913
2023-01-30 2021-12-31 13F/A-1 MERCK COM 58933Y105 49,989 10,328 26.04 3,831 28.60 0.2968
2022-02-11 2021-12-31 13F MERCK COM 58933Y105 49,989 10,328 3,831 0.2968
2023-01-30 2021-09-30 13F/A-1 MERCK COM 58933Y105 39,661 3,639 10.10 2,979 6.35 0.2910
2021-11-15 2021-09-30 13F MERCK COM 58933Y105 39,661 3,639 2,979 0.2910
2023-01-30 2021-06-30 13F/A-1 MERCK COM 58933Y105 36,022 6,233 20.92 2,801 21.99 0.3328
2021-08-13 2021-06-30 13F MERCK COM 58933Y105 36,022 6,233 2,801 0.3328
2023-01-30 2021-03-31 13F/A-1 MERCK & CO. COM 58933Y105 29,789 16,805 129.43 2,296 116.20 0.3568
2021-05-17 2021-03-31 13F MERCK & CO. COM 58933Y105 29,789 16,805 2,296 0.3568
2023-01-30 2020-12-31 13F/A-1 MERCK & CO. COM 58933Y105 12,984 -4,142 -24.19 1,062 -25.26 0.2115
2021-02-16 2020-12-31 13F MERCK & CO. COM 58933Y105 12,984 -4,142 1,062 0.2115
2023-01-30 2020-09-30 13F/A-1 MERCK & CO. COM 58933Y105 17,126 4,012 30.59 1,421 40.14 0.3394
2020-11-16 2020-09-30 13F MERCK & CO. COM 58933Y105 17,126 4,012 1,421 0.3394
2020-08-17 2020-06-30 13F MERCK & CO. COM 58933Y105 13,114 -2,122 -13.93 1,014 -13.55 0.2579
2020-05-14 2020-03-31 13F MERCK & CO. COM 58933Y105 15,236 3,106 25.61 1,173 6.35 0.3027
2020-02-12 2019-12-31 13F MERCK COM 58933Y105 12,130 1,425 13.31 1,103 22.42 0.2704
2019-11-13 2019-09-30 13F MERCK COM 58933Y105 10,705 5,223 95.28 901 95.87 0.2292
2019-08-14 2019-06-30 13F MERCK COM 58933Y105 5,482 1,943 54.90 460 56.46 0.1402
2019-05-10 2019-03-31 13F MERCK COM 58933Y105 3,539 65 1.87 294 10.94 0.1079
2019-02-13 2018-12-31 13F MERCK COM 58933Y105 3,474 3,474 265 0.1543
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.