Merck & Co., Inc.
MX ˙ BMV ˙ US58933Y1055
SecurityMX:MRK / Merck & Co., Inc.
InstitutionGladius Capital Management LP
Latest Disclosed Ownership7,500 shares
Latest Disclosed Value $ 902,175
Gladius Capital Management LP ownership in MRK / Merck & Co., Inc.

On May 7, 2026 - Gladius Capital Management LP filed a 13F-HR form disclosing ownership of 7,500 shares of Merck & Co., Inc. (MX:MRK) valued at $902,175 USD as of March 31, 2026. The entity filed a previous 13F-HR on August 5, 2025 disclosing 0 shares of Merck & Co., Inc..

Gladius Capital Management LP has a history of taking positions in derivatives of the underlying security (MRK) in the form of stock options. The firm currently holds call options representing 61,000 of underlying shares valued at $7,337,690 USD and put options representing 81,200 of underlying shares valued at $9,767,548 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.

MX:MRK / 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)
2026-05-07 2026-03-31 13F MERCK COM 58933Y105 7,500 7,500 902 0.0402
2025-08-05 2025-06-30 13F MERCK COM 58933Y105 0 -11,848 -100.00 0 -100.00
2025-05-08 2025-03-31 13F MERCK COM 58933Y105 11,848 -291 -2.40 1,063 -11.93 0.2828
2025-01-31 2024-12-31 13F MERCK COM 58933Y105 12,139 -2,724 -18.33 1,208 -28.45 0.1296
2024-11-15 2024-09-30 13F/A-1 MERCK COM 58933Y105 14,863 9,246 164.61 1,688 142.73 0.2034
2024-11-06 2024-09-30 13F MERCK COM 58933Y105 14,863 9,246 1,688 0.2034
2024-07-18 2024-06-30 13F MERCK COM 58933Y105 5,617 4,292 323.92 695 299.43 0.0853
2024-05-14 2024-03-31 13F MERCK COM 58933Y105 1,325 1,325 175 0.0577
2024-02-07 2023-12-31 13F MERCK COM 58933Y105 0 -35,938 -100.00 0 -100.00
2023-12-18 2023-09-30 13F/A-1 MERCK COM 58933Y105 35,938 35,938 3,700 0.1544
2023-10-10 2023-09-30 13F MERCK COM 58933Y105 35,938 35,938 4 0.1544
2023-12-18 2023-06-30 13F/A-1 MERCK COM 58933Y105 0 -20,638 -100.00 0 -100.00
2023-08-08 2023-06-30 13F MERCK COM 58933Y105 0 -20,638 0
2023-12-18 2023-03-31 13F/A-1 MERCK COM 58933Y105 20,638 17,955 669.21 2,196 639.06 0.1278
2023-05-09 2023-03-31 13F MERCK COM 58933Y105 20,638 17,955 2 0.1278
2023-12-18 2022-12-31 13F/A-1 MERCK COM 58933Y105 2,683 -8,223 -75.40 298 -68.40 0.0214
2023-02-02 2022-12-31 13F MERCK COM 58933Y105 2,683 -8,223 0 0.0214
2022-11-14 2022-09-30 13F MERCK COM 58933Y105 10,906 9,343 597.76 940 557.34 0.0414
2022-08-10 2022-06-30 13F MERCK COM 58933Y105 1,563 896 134.33 143 160.00 0.0074
2022-04-29 2022-03-31 13F MERCK COM 58933Y105 667 -1,798 -72.94 55 -70.90 0.0041
2022-02-08 2021-12-31 13F MERCK COM 58933Y105 2,465 2,465 189 0.0151
2021-08-06 2021-06-30 13F MERCK & CO. COM 58933Y105 0 -24,305 -100.00 0 -100.00
2021-05-13 2021-03-31 13F MERCK & CO. COM 58933Y105 24,305 14,872 157.66 1,874 142.75 0.0707
2021-02-09 2020-12-31 13F MERCK & CO. COM 58933Y105 9,433 6,059 179.58 772 175.71 0.0381
2020-11-12 2020-09-30 13F MERCK & CO. COM 58933Y105 3,374 3,374 280 0.0279
2020-08-07 2020-06-30 13F MERCK & CO. COM 58933Y105 0 -11,471 -100.00 0 -100.00
2020-05-07 2020-03-31 13F MERCK & CO. COM 58933Y105 11,471 11,471 883 0.0930
2020-02-13 2019-12-31 13F MERCK COM 58933Y105 0 -61,280 -100.00 0 -100.00
2019-11-14 2019-09-30 13F MERCK COM 58933Y105 61,280 13,557 28.41 5,159 27.54 0.2352
2019-08-13 2019-06-30 13F MERCK COM 58933Y105 47,723 24,106 102.07 4,045 105.96 0.2410
2019-05-15 2019-03-31 13F MERCK COM 58933Y105 23,617 -37,248 -61.20 1,964 -57.77 0.1084
2019-02-14 2018-12-31 13F MERCK COM 58933Y105 60,865 58,143 2,136.04 4,651 2,309.84 0.2267
2018-11-14 2018-09-30 13F MERCK COM 58933Y105 2,722 -22,778 -89.33 193 -87.53 0.0186
2018-08-10 2018-06-30 13F MERCK PUT 58933Y955 25,500 25,500 1,548 0.1576
2018-08-10 2018-06-30 13F MERCK COM 58933Y105 10,799 -14,701 655 0.0667
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
(%)
2026-05-07 2026-03-31 13F MERCK CALL Call 61,000 7,338 n/a n/a n/a
2024-05-14 2024-03-31 13F MERCK CALL Call 0 -100.00 0 -100.00 n/a n/a n/a
2024-02-07 2023-12-31 13F MERCK CALL Call 14,100 -66.27 1,537 -64.28 n/a n/a n/a
2023-12-18 2023-09-30 13F/A MERCK CALL Call 41,800 55.97 4,303 39.17 n/a n/a n/a
2023-10-10 2023-09-30 13F MERCK CALL Call 41,800 4 n/a n/a n/a
2023-12-18 2023-06-30 13F/A MERCK CALL Call 26,800 33.33 3,092 44.62 n/a n/a n/a
2023-08-08 2023-06-30 13F MERCK CALL Call 26,800 3 n/a n/a n/a
2023-12-18 2023-03-31 13F/A MERCK CALL Call 20,100 2,138 n/a n/a n/a
2023-05-09 2023-03-31 13F MERCK CALL Call 20,100 2 n/a n/a n/a
2021-11-12 2021-09-30 13F MERCK CALL Call 0 -100.00 0 -100.00 n/a n/a n/a
2021-08-06 2021-06-30 13F MERCK CALL Call 4,600 -93.20 358 -93.13 n/a n/a n/a
2021-05-13 2021-03-31 13F MERCK & CO. CALL Call 67,600 20.71 5,212 13.77 n/a n/a n/a
2021-02-09 2020-12-31 13F MERCK & CO. CALL Call 56,000 551.16 4,581 541.60 n/a n/a n/a
2020-11-12 2020-09-30 13F MERCK & CO. CALL Call 8,600 714 n/a n/a n/a
2020-08-07 2020-06-30 13F MERCK & CO. CALL Call 0 -100.00 0 -100.00 n/a n/a n/a
2020-05-07 2020-03-31 13F MERCK & CO. CALL Call 17,200 -42.86 1,324 -51.64 n/a n/a n/a
2020-02-13 2019-12-31 13F MERCK CALL Call 30,100 40.00 2,738 51.27 n/a n/a n/a
2019-11-14 2019-09-30 13F MERCK CALL Call 21,500 202.82 1,810 200.66 n/a n/a n/a
2019-08-13 2019-06-30 13F MERCK CALL Call 7,100 602 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
(%)
2026-05-07 2026-03-31 13F MERCK PUT Put 81,200 9,768 n/a n/a n/a
2025-08-05 2025-06-30 13F MERCK PUT Put 0 -100.00 0 -100.00 n/a n/a n/a
2025-05-08 2025-03-31 13F MERCK PUT Put 25,300 -39.76 2,271 -45.67 n/a n/a n/a
2025-01-31 2024-12-31 13F MERCK PUT Put 42,000 -2.78 4,178 -14.82 n/a n/a n/a
2024-11-15 2024-09-30 13F/A MERCK PUT Put 43,200 163.41 4,906 141.63 n/a n/a n/a
2024-11-06 2024-09-30 13F MERCK PUT Put 43,200 4,906 n/a n/a n/a
2024-07-18 2024-06-30 13F MERCK PUT Put 16,400 13.10 2,030 6.12 n/a n/a n/a
2024-05-14 2024-03-31 13F MERCK PUT Put 14,500 -56.85 1,913 -47.78 n/a n/a n/a
2024-02-07 2023-12-31 13F MERCK PUT Put 33,600 -61.73 3,663 -59.48 n/a n/a n/a
2023-12-18 2023-09-30 13F/A MERCK PUT Put 87,800 73.18 9,039 54.51 n/a n/a n/a
2023-10-10 2023-09-30 13F MERCK PUT Put 87,800 9 n/a n/a n/a
2023-12-18 2023-06-30 13F/A MERCK PUT Put 50,700 -37.56 5,850 -32.28 n/a n/a n/a
2023-08-08 2023-06-30 13F MERCK PUT Put 50,700 6 n/a n/a n/a
2023-12-18 2023-03-31 13F/A MERCK PUT Put 81,200 407.50 8,639 386.65 n/a n/a n/a
2023-05-09 2023-03-31 13F MERCK PUT Put 81,200 9 n/a n/a n/a
2023-12-18 2022-12-31 13F/A MERCK PUT Put 16,000 -55.56 1,775 -42.76 n/a n/a n/a
2023-02-02 2022-12-31 13F MERCK PUT Put 16,000 2 n/a n/a n/a
2022-11-14 2022-09-30 13F MERCK PUT Put 36,000 110.53 3,101 98.78 n/a n/a n/a
2022-08-10 2022-06-30 13F MERCK PUT Put 17,100 116.46 1,560 140.37 n/a n/a n/a
2022-04-29 2022-03-31 13F MERCK PUT Put 7,900 649 n/a n/a n/a
2021-08-06 2021-06-30 13F MERCK & CO. PUT Put 0 -100.00 0 -100.00 n/a n/a n/a
2021-05-13 2021-03-31 13F MERCK & CO. PUT Put 200,700 20.69 15,472 13.73 n/a n/a n/a
2021-02-09 2020-12-31 13F MERCK & CO. PUT Put 166,300 525.19 13,604 516.40 n/a n/a n/a
2020-11-12 2020-09-30 13F MERCK & CO. PUT Put 26,600 2,207 n/a n/a n/a
2020-08-07 2020-06-30 13F MERCK & CO. PUT Put 0 -100.00 0 -100.00 n/a n/a n/a
2020-05-07 2020-03-31 13F MERCK & CO. PUT Put 41,900 -60.51 3,224 -66.59 n/a n/a n/a
2020-02-13 2019-12-31 13F MERCK PUT Put 106,100 -81.08 9,650 -79.56 n/a n/a n/a
2019-11-14 2019-09-30 13F MERCK PUT Put 560,900 42.00 47,217 41.04 n/a n/a n/a
2019-08-13 2019-06-30 13F MERCK PUT Put 395,000 96.62 33,477 100.35 n/a n/a n/a
2019-05-15 2019-03-31 13F MERCK PUT Put 200,900 1.26 16,709 10.22 n/a n/a n/a
2019-02-14 2018-12-31 13F MERCK PUT Put 198,400 867.80 15,160 942.64 n/a n/a n/a
2018-11-14 2018-09-30 13F MERCK PUT Put 20,500 -19.61 1,454 -6.07 n/a n/a n/a
2018-08-10 2018-06-30 13F MERCK PUT 25,500 1,548 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.