Merck & Co., Inc.
BG ˙ BUL ˙ US58933Y1055
SecurityBG:6MK / Merck & Co., Inc.
InstitutionKovack Advisors, Inc.
Latest Disclosed Ownership37,767 shares
Latest Disclosed Value $ 4,548,482
Kovack Advisors, Inc. ownership in 6MK / Merck & Co., Inc.

On May 12, 2026 - Kovack Advisors, Inc. filed a 13F-HR form disclosing ownership of 37,767 shares of Merck & Co., Inc. (BG:6MK) valued at $4,548,482 USD as of March 31, 2026. The entity filed a previous 13F-HR/A on February 17, 2026 disclosing 21,536 shares of Merck & Co., Inc.. This represents a change in shares of 75.37% during the quarter.

Kovack Advisors, Inc. has a history of taking positions in derivatives of the underlying security (6MK) in the form of stock options. The firm currently holds call options representing 0 of underlying shares valued at $0 USD and put options representing 0 of underlying shares valued at $0 USD .

Note: prior versions of this page mistakenly stated that the share values represented the number of options, not the number of underlying shares. For more information on the data backing these reports, please see the SEC document Frequently Asked Questions About Form 13F.

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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Institutional Put/Call Ratios
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In addition to reporting standard equity and debt issues, institutions with more than 100MM assets under management must also disclose their put and call option holdings. Since put options generally indicate negative sentiment, and call options indicate positive sentiment, we can get a sense of the overall institutional sentiment by plotting the ratio of puts to calls. The chart to the right plots the historical put/call ratio for this instrument.

Using Put/Call Ratio as an indicator of investor sentiment overcomes one of the key deficiencies of using total institutional ownership, which is that a significant amount of assets under management are invested passively to track indices. Passively-managed funds do not typically buy options, so the put/call ratio indicator more closely tracks the sentiment of actively-managed funds.

BG:6MK / Merck & Co., Inc. Historical Put/Call Ratio
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 COM 58933Y105 37,767 16,231 75.37 4,548 100.71 0.2426
2026-02-17 2025-12-31 13F/A-1 MERCK COM 58933Y105 21,536 13,007 152.50 2,267 216.92 0.1053
2026-02-12 2025-12-31 13F MERCK COM 58933Y105 21,537 13,008 1,080
2025-11-10 2025-09-30 13F MERCK COM 58933Y105 8,529 -3,144 -26.93 716 -22.54 0.0674
2025-08-04 2025-06-30 13F MERCK COM 58933Y105 11,673 -1,408 -10.76 924 -21.38 0.0906
2025-05-06 2025-03-31 13F MERCK COM 58933Y105 13,081 -2,254 -14.70 1,174 -23.02 0.1243
2025-02-05 2024-12-31 13F MERCK COM 58933Y105 15,335 -8,570 -35.85 1,526 -43.81 0.1497
2024-11-05 2024-09-30 13F MERCK COM 58933Y105 23,905 -2,064 -7.95 2,715 -15.56 0.2875
2024-08-05 2024-06-30 13F MERCK COM 58933Y105 25,969 73 0.28 3,215 -5.94 0.3538
2024-04-19 2024-03-31 13F MERCK COM 58933Y105 25,896 2,063 8.66 3,417 31.52 0.4137
2024-02-02 2023-12-31 13F MERCK COM 58933Y105 23,833 -243 -1.01 2,598 4.84 0.3086
2023-10-19 2023-09-30 13F MERCK COM 58933Y105 24,076 715 3.06 2,479 -8.05 0.3457
2023-07-21 2023-06-30 13F MERCK COM 58933Y105 23,361 3,166 15.68 2,696 25.47 0.3454
2023-04-21 2023-03-31 13F MERCK COM 58933Y105 20,195 -548 -2.64 2,149 -6.65 0.2929
2023-02-22 2022-12-31 13F MERCK & CO ORD ORD 58933Y105 20,743 -653 -3.05 2,301 24.85 0.3364
2022-11-14 2022-09-30 13F MERCK & CO ORD ORD 58933Y105 21,396 -2,478 -10.38 1,843 -15.34 0.2707
2022-08-10 2022-06-30 13F MERCK & CO ORD ORD 58933Y105 23,874 789 3.42 2,177 14.94 0.2873
2022-05-16 2022-03-31 13F MERCK & CO ORD ORD 58933Y105 23,085 701 3.13 1,894 10.37 0.1946
2022-01-18 2021-12-31 13F MERCK & CO ORD ORD 58933Y105 22,384 1,175 5.54 1,716 7.72 0.1658
2021-11-03 2021-09-30 13F MERCK & CO ORD ORD 58933Y105 21,209 1,237 6.19 1,593 2.58 0.1731
2021-07-29 2021-06-30 13F MERCK & CO ORD ORD 58933Y105 19,972 871 4.56 1,553 5.50 0.1768
2021-05-04 2021-03-31 13F MERCK & CO ORD ORD 58933Y105 19,101 2,984 18.51 1,472 11.68 0.1913
2021-01-14 2020-12-31 13F MERCK & CO ORD ORD 58933Y105 16,117 -70 -0.43 1,318 -1.86 0.1897
2020-11-02 2020-09-30 13F MERCK & CO ORD ORD 58933Y105 16,187 -173 -1.06 1,343 6.17 0.2390
2020-07-31 2020-06-30 13F MERCK & CO ORD ORD 58933Y105 16,360 -2,383 -12.71 1,265 -12.27 0.2463
2020-04-30 2020-03-31 13F MERCK & CO ORD ORD 58933Y105 18,743 -1,205 -6.04 1,442 -20.51 0.3330
2020-01-29 2019-12-31 13F MERCK & CO JAN 17, 2020 CALL 87.5 ORD 58933Y105 19,948 1,254 6.71 1,814 15.25 0.3243
2019-10-31 2019-09-30 13F MERCK & CO ORD ORD 58933Y105 18,694 807 4.51 1,574 4.93 0.3229
2019-08-14 2019-06-30 13F MERCK & CO INC COM COM 58933Y105 17,887 400 2.29 1,500 3.16 0.3429
2019-05-03 2019-03-31 13F MERCK & CO INC COM COM 58933Y105 17,487 -632 -3.49 1,454 5.06 0.3625
2019-02-06 2018-12-31 13F MERCK & CO INC COM COM 58933Y105 18,119 1,684 10.25 1,384 18.70 0.4047
2018-10-09 2018-09-30 13F MERCK & CO INC COM COM 58933Y105 16,435 1,617 10.91 1,166 29.70 0.3007
2018-08-01 2018-06-30 13F MERCK & CO INC COM COM 58933Y105 14,818 -4,456 -23.12 899 -14.38 0.2511
2018-05-15 2018-03-31 13F MERCK & CO INC COM COM 58933Y105 19,274 -154 -0.79 1,050 -3.93 0.2634
2018-05-15 2017-12-31 13F/A-1 MERCK COM 58933Y105 19,428 4,921 33.92 1,093 17.65 0.2762
2018-02-01 2017-12-31 13F MERCK COM COM 58933Y105 19,479 1,096
2018-08-02 2017-09-30 13F MERCK & CO INC COM COM 58933Y105 14,507 -838 -5.46 929 -5.49 0.3082
2018-08-30 2017-06-30 13F MERCK & CO INC COM COM 58933Y105 15,345 2,305 17.68 983 18.58 0.3102
2018-09-05 2017-03-31 13F MERCK & CO INC COM COM 58933Y105 13,040 -1,724 -11.68 829 -4.60 0.3228
2018-09-10 2016-12-31 13F MERCK & CO INC COM COM 58933Y105 14,764 2,747 22.86 869 15.87 0.4135
2018-09-25 2016-09-30 13F MERCK & CO INC COM COM 58933Y105 12,017 6,483 117.15 750 135.11 0.3651
2018-10-01 2016-06-30 13F MERCK & CO INC COM COM 58933Y105 5,534 -306 -5.24 319 3.24 0.1693
2018-10-12 2016-03-31 13F MERCK & CO INC COM COM 58933Y105 5,840 -759 -11.50 309 -11.46 0.1931
2018-10-18 2015-12-31 13F MERCK & CO INC COM COM 58933Y105 6,599 -1,446 -17.97 349 -12.09 0.2301
2018-10-29 2015-09-30 13F MERCK & CO INC COM 58933Y105 8,045 2,234 38.44 397 19.94 0.2770
2018-11-06 2015-06-30 13F MERCK & CO INC COM COM 58933Y105 5,811 2,223 61.96 331 62.25 0.2341
2018-11-19 2014-12-31 13F MERCK & CO INC COM COM 58933Y105 3,588 -337 -8.59 204 -12.45 0.2106
2018-12-04 2014-09-30 13F MERCK & CO INC COM COM 58933Y105 3,925 -97 -2.41 233 9.39 0.3427
2019-01-28 2014-03-31 13F MERCK & CO INC COM COM 58933Y105 4,022 -795 -16.50 213 -11.62 0.7285
2019-03-15 2013-12-31 13F MERCK & CO INC COM COM 58933Y105 4,817 -195 -3.89 241 0.84 1.3096
2019-04-09 2013-09-30 13F MERCK & CO INC COM COM 58933Y105 5,012 -1,170 -18.93 239 -16.72 1.2287
2019-05-07 2013-06-30 13F MERCK & CO INC COM COM 58933Y105 6,182 -1,489 -19.41 287 -15.34 1.6906
2019-05-20 2013-03-31 13F MERCK & CO INC COM COM 58933Y105 7,671 7,671 339 1.8114
Disclosed Call Options
File
Date
Effective
Date
Form Security Class ID Opt Avg Share
Price
Shares ΔShares
(%)
Value
(x1000)
ΔValue
(%)
Prior Allocation
(%)
Allocation
(%)
ΔAllocation
(%)
Cost Basis
(x1000)
Profit
(x1000)
Return
(%)
2020-01-29 2019-12-31 13F MERCK & CO JAN 17, 2020 CALL 87.5 ORD Call 0 -100.00 0 n/a n/a n/a
2019-10-31 2019-09-30 13F MERCK & CO JAN 17, 2020 CALL 87.5 ORD Call 1 0.00 0 n/a n/a n/a
2019-08-14 2019-06-30 13F MERCK & CO INC CALL JAN00087500 COM Call 1 -80.00 0 -100.00 n/a n/a n/a
2019-03-15 2013-12-31 13F MERCK & CO INC CALL JAN00049000 COM Call 5 -28.57 1 0.00 n/a n/a n/a
2019-04-09 2013-09-30 13F MERCK & CO INC CALL JAN00049000 COM Call 7 -36.36 1 -50.00 n/a n/a n/a
2019-05-07 2013-06-30 13F MERCK & CO INC CALL JAN00049000 COM Call 11 -68.57 2 -66.67 n/a n/a n/a
2019-05-20 2013-03-31 13F MERCK & CO INC CALL JUL00044000 COM Call 35 6 n/a n/a n/a
Disclosed Put Options
File
Date
Effective
Date
Form Security Class ID Opt Avg Share Price Shares ΔShares
(%)
Value
(x1000)
ΔValue
(%)
Prior Allocation
(%)
Allocation
(%)
ΔAllocation
(%)
Cost Basis
(x1000)
Profit
(x1000)
Return
(%)
2020-11-02 2020-09-30 13F MERCK & CO JUL 17, 2020 PUT 77.5 ORD Put 0 -100.00 0 -100.00 n/a n/a n/a
2020-07-31 2020-06-30 13F MERCK & CO JUL 17, 2020 PUT 77.5 ORD Put 4 1 n/a n/a n/a
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.