Merck & Co., Inc.
BG ˙ BUL ˙ US58933Y1055
SecurityBG:6MK / Merck & Co., Inc.
InstitutionIMC-Chicago, LLC
Latest Disclosed Ownership0 shares
Latest Disclosed Value $ 0
IMC-Chicago, LLC ownership in 6MK / Merck & Co., Inc.

On January 29, 2026 - IMC-Chicago, LLC filed a 13F-HR form disclosing ownership of 0 shares of Merck & Co., Inc. (BG:6MK) valued at $0 USD as of December 31, 2025. The entity filed a previous 13F-HR on November 4, 2025 disclosing 19,187 shares of Merck & Co., Inc.. This represents a change in shares of -100.00% during the quarter.

IMC-Chicago, LLC 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 911,200 of underlying shares valued at $109,608,248 USD and put options representing 742,500 of underlying shares valued at $89,315,325 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.

Upgrade to unlock premium data and export to Excel .

Institutional Put/Call Ratios
(Premium Subscription Required)

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)
2026-01-29 2025-12-31 13F MERCK COM 58933Y105 0 -19,187 -100.00 0 -100.00
2025-11-04 2025-09-30 13F MERCK COM 58933Y105 19,187 19,187 1,610 0.0006
2025-04-14 2025-03-31 13F MERCK COM 58933Y105 0 -18,557 -100.00 0 -100.00
2025-01-27 2024-12-31 13F MERCK COM 58933Y105 18,557 18,557 1,846 0.0009
2024-10-25 2024-09-30 13F MERCK COM 58933Y105 0 -11,656 -100.00 0 -100.00
2024-07-15 2024-06-30 13F MERCK COM 58933Y105 11,656 11,656 1,443 0.0009
2021-11-05 2021-09-30 13F MERCK COM 58933Y105 0 -25,724 -100.00 0 -100.00
2021-08-06 2021-06-30 13F MERCK COM 58933Y105 25,724 25,724 718 0.0009
2020-05-14 2020-03-31 13F MERCK COM 58933Y105 0 -47,844 -100.00 0 -100.00
2020-02-13 2019-12-31 13F MERCK COM 58933Y105 47,844 24,156 101.98 4,351 118.20 0.0112
2019-11-12 2019-09-30 13F MERCK COM 58933Y105 23,688 -14,974 -38.73 1,994 -38.49 0.0062
2019-08-15 2019-06-30 13F MERCK COM 58933Y105 38,662 38,662 3,242 0.0105
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
(%)
2026-05-05 2026-03-31 13F MERCK COM Call 911,200 -9.69 109,608 3.20 n/a n/a n/a
2026-01-29 2025-12-31 13F MERCK COM Call 1,009,000 13.46 106,207 42.30 n/a n/a n/a
2025-11-04 2025-09-30 13F MERCK COM Call 889,300 1.28 74,639 7.38 n/a n/a n/a
2025-07-22 2025-06-30 13F MERCK COM Call 878,100 -1.67 69,510 -13.28 n/a n/a n/a
2025-04-14 2025-03-31 13F MERCK COM Call 893,000 17.42 80,156 5.95 n/a n/a n/a
2025-01-27 2024-12-31 13F MERCK COM Call 760,500 49.32 75,655 30.81 n/a n/a n/a
2024-10-25 2024-09-30 13F MERCK COM Call 509,300 26.47 57,836 16.01 n/a n/a n/a
2024-07-15 2024-06-30 13F MERCK COM Call 402,700 34.32 49,854 26.03 n/a n/a n/a
2024-04-12 2024-03-31 13F MERCK COM Call 299,800 34.92 39,559 63.30 n/a n/a n/a
2024-02-09 2023-12-31 13F MERCK COM Call 222,200 2.59 24,224 8.64 n/a n/a n/a
2023-10-12 2023-09-30 13F MERCK COM Call 216,600 7.33 22,299 -4.24 n/a n/a n/a
2023-07-14 2023-06-30 13F MERCK COM Call 201,800 -18.96 23,286 -12.10 n/a n/a n/a
2023-04-24 2023-03-31 13F MERCK COM Call 249,000 -30.93 26,491 -33.77 n/a n/a n/a
2023-04-24 2022-12-31 13F/A MERCK COM Call 360,500 18.12 39,997 52.17 n/a n/a n/a
2023-02-09 2022-12-31 13F MERCK COM Call 360,500 40 n/a n/a n/a
2022-11-08 2022-09-30 13F MERCK COM Call 305,200 -30.65 26,284 -34.49 n/a n/a n/a
2022-08-05 2022-06-30 13F MERCK COM Call 440,100 10.05 40,124 22.28 n/a n/a n/a
2022-04-19 2022-03-31 13F MERCK & CO. COM Call 399,900 32,812 n/a n/a n/a
2022-02-07 2021-12-31 13F MERCK COM Call 0 -100.00 0 -100.00 n/a n/a n/a
2021-11-05 2021-09-30 13F MERCK COM Call 637,000 103.38 24,206 176.77 n/a n/a n/a
2021-08-06 2021-06-30 13F MERCK COM Call 313,200 -24.93 8,746 -72.81 n/a n/a n/a
2021-05-14 2021-03-31 13F MERCK & CO. COM Call 417,200 102.13 32,162 90.49 n/a n/a n/a
2021-02-17 2020-12-31 13F MERCK & CO. COM Call 206,400 2.03 16,884 0.61 n/a n/a n/a
2020-11-17 2020-09-30 13F MERCK & CO. COM Call 202,300 173.38 16,781 193.27 n/a n/a n/a
2020-08-14 2020-06-30 13F MERCK & CO. COM Call 74,000 -58.05 5,722 -57.84 n/a n/a n/a
2020-05-14 2020-03-31 13F MERCK & CO. COM Call 176,400 11.01 13,572 -6.09 n/a n/a n/a
2020-02-13 2019-12-31 13F MERCK COM Call 158,900 27.73 14,452 38.01 n/a n/a n/a
2019-11-12 2019-09-30 13F MERCK COM Call 124,400 41.04 10,472 41.59 n/a n/a n/a
2019-08-15 2019-06-30 13F MERCK COM Call 88,200 -2.65 7,396 -1.84 n/a n/a n/a
2019-05-15 2019-03-31 13F MERCK COM Call 90,600 26.01 7,535 37.15 n/a n/a n/a
2019-04-24 2018-12-31 13F MERCK COM Call 71,900 5,494 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
(%)
2026-05-05 2026-03-31 13F MERCK COM Put 742,500 2.83 89,315 17.51 n/a n/a n/a
2026-01-29 2025-12-31 13F MERCK COM Put 722,100 -9.11 76,008 13.99 n/a n/a n/a
2025-11-04 2025-09-30 13F MERCK COM Put 794,500 30.76 66,682 38.64 n/a n/a n/a
2025-07-22 2025-06-30 13F MERCK COM Put 607,600 1.08 48,098 -10.86 n/a n/a n/a
2025-04-14 2025-03-31 13F MERCK COM Put 601,100 33.58 53,955 20.52 n/a n/a n/a
2025-01-27 2024-12-31 13F MERCK COM Put 450,000 21.00 44,766 6.00 n/a n/a n/a
2024-10-25 2024-09-30 13F MERCK COM Put 371,900 14.01 42,233 4.58 n/a n/a n/a
2024-07-15 2024-06-30 13F MERCK COM Put 326,200 -20.40 40,384 -25.32 n/a n/a n/a
2024-04-12 2024-03-31 13F MERCK COM Put 409,800 122.48 54,073 169.27 n/a n/a n/a
2024-02-09 2023-12-31 13F MERCK COM Put 184,200 2.96 20,081 9.04 n/a n/a n/a
2023-10-12 2023-09-30 13F MERCK COM Put 178,900 -10.46 18,418 -20.11 n/a n/a n/a
2023-07-14 2023-06-30 13F MERCK COM Put 199,800 -13.69 23,055 -6.39 n/a n/a n/a
2023-04-24 2023-03-31 13F MERCK COM Put 231,500 -44.91 24,629 -47.17 n/a n/a n/a
2023-04-24 2022-12-31 13F/A MERCK COM Put 420,200 42.97 46,621 84.19 n/a n/a n/a
2023-02-09 2022-12-31 13F MERCK COM Put 420,200 47 n/a n/a n/a
2022-11-08 2022-09-30 13F MERCK COM Put 293,900 -24.25 25,311 -28.45 n/a n/a n/a
2022-08-05 2022-06-30 13F MERCK COM Put 388,000 25.08 35,374 38.98 n/a n/a n/a
2022-04-19 2022-03-31 13F MERCK & CO. COM Put 310,200 25,452 n/a n/a n/a
2022-02-07 2021-12-31 13F MERCK COM Put 0 -100.00 0 -100.00 n/a n/a n/a
2021-11-05 2021-09-30 13F MERCK COM Put 519,700 96.04 19,749 166.77 n/a n/a n/a
2021-08-06 2021-06-30 13F MERCK COM Put 265,100 -3.32 7,403 -64.98 n/a n/a n/a
2021-05-14 2021-03-31 13F MERCK & CO. COM Put 274,200 34.41 21,138 26.67 n/a n/a n/a
2021-02-17 2020-12-31 13F MERCK & CO. COM Put 204,000 36.55 16,687 34.65 n/a n/a n/a
2020-11-17 2020-09-30 13F MERCK & CO. COM Put 149,400 133.07 12,393 150.01 n/a n/a n/a
2020-08-14 2020-06-30 13F MERCK & CO. COM Put 64,100 -53.68 4,957 -53.45 n/a n/a n/a
2020-05-14 2020-03-31 13F MERCK & CO. COM Put 138,400 -33.17 10,648 -43.47 n/a n/a n/a
2020-02-13 2019-12-31 13F MERCK COM Put 207,100 -2.08 18,836 5.80 n/a n/a n/a
2019-11-12 2019-09-30 13F MERCK COM Put 211,500 65.88 17,804 66.53 n/a n/a n/a
2019-08-15 2019-06-30 13F MERCK COM Put 127,500 37.84 10,691 38.97 n/a n/a n/a
2019-05-15 2019-03-31 13F MERCK COM Put 92,500 -19.28 7,693 -12.15 n/a n/a n/a
2019-04-24 2018-12-31 13F MERCK COM Put 114,600 8,757 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.