Merck & Co., Inc.
MX ˙ BMV ˙ US58933Y1055
SecurityMX:MRK / Merck & Co., Inc.
InstitutionLeonteq Securities AG
Latest Disclosed Ownership120,645 shares
Latest Disclosed Value $ 14,512,389
Leonteq Securities AG ownership in MRK / Merck & Co., Inc.

On April 27, 2026 - Leonteq Securities AG filed a 13F-HR form disclosing ownership of 120,645 shares of Merck & Co., Inc. (MX:MRK) valued at $14,512,389 USD as of March 31, 2026. The entity filed a previous 13F-HR on February 6, 2026 disclosing 138,929 shares of Merck & Co., Inc.. This represents a change in shares of -13.16% during the quarter.

Leonteq Securities AG 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 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.

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.

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)
2026-04-27 2026-03-31 13F MERCK COM 58933Y105 120,645 -18,284 -13.16 14,512 -0.76 0.5368
2026-02-06 2025-12-31 13F MERCK COM 58933Y105 138,929 -6,993 -4.79 14,624 19.40 0.4463
2026-02-17 2025-09-30 13F MERCK COM 58933Y105 145,922 -47,324 -24.49 12,247 -19.94 0.3712
2026-02-17 2025-06-30 13F MERCK COM 58933Y105 193,246 145,376 303.69 15,297 256.41 0.5905
2026-02-23 2025-03-31 13F MERCK COM 58933Y105 47,870 13,857 40.74 4,293 26.87 0.2416
2026-02-23 2024-12-31 13F MERCK COM 58933Y105 34,013 -13,728 -28.76 3,384 -37.59 0.2289
2026-03-04 2024-09-30 13F MERCK COM 58933Y105 47,741 25,639 116.00 5,421 98.14 0.4124
2026-03-04 2024-06-30 13F MERCK COM 58933Y105 22,102 21,210 2,377.80 2,736 2,238.46 0.1939
2026-03-11 2024-03-31 13F MERCK COM 58933Y105 892 -22,074 -96.12 118 -95.33 0.0088
2026-03-11 2023-12-31 13F MERCK COM 58933Y105 22,966 -1,949 -7.82 2,504 -2.42 0.1428
2026-03-11 2023-09-30 13F MERCK COM 58933Y105 24,915 8,102 48.19 2,565 32.22 0.1421
2026-03-11 2023-06-30 13F MERCK COM 58933Y105 16,813 -2,054 -10.89 1,940 -3.34 0.1004
2026-03-11 2023-03-31 13F MERCK COM 58933Y105 18,867 1,775 10.38 2,007 5.85 0.0915
2026-03-26 2022-12-31 13F MERCK COM 58933Y105 17,092 -12,754 -42.73 1,896 -26.23 0.0704
2026-03-26 2022-09-30 13F MERCK COM 58933Y105 29,846 14,277 91.70 2,570 81.11 0.0998
2026-03-26 2022-06-30 13F MERCK COM 58933Y105 15,569 -1,235 -7.35 1,419 2.98 0.0534
2026-03-26 2022-03-31 13F MERCK COM 58933Y105 16,804 -10,271 -37.94 1,379 -33.59 0.0492
2026-03-26 2021-12-31 13F MERCK COM 58933Y105 27,075 21,019 347.08 2,075 357.05 0.0747
2026-03-26 2021-09-30 13F MERCK COM 58933Y105 6,056 -16,366 -72.99 455 -73.95 0.0194
2026-03-26 2021-06-30 13F MERCK COM 58933Y105 22,422 -41,990 -65.19 1,744 -64.89 0.1039
2026-03-26 2021-03-31 13F MERCK & CO. COM 58933Y105 64,412 -6,720 -9.45 4,966 -14.66 0.2949
2026-03-26 2020-12-31 13F MERCK & CO. COM 58933Y105 71,132 71,132 5,819 0.3114
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
(%)
2026-03-04 2024-06-30 13F MERCK COM Call 0 -100.00 0 -100.00 n/a n/a n/a
2026-03-11 2024-03-31 13F MERCK COM Call 25,000 3,299 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
(%)
2026-03-26 2021-03-31 13F MERCK & CO. COM Put 0 -100.00 0 -100.00 n/a n/a n/a
2026-03-26 2020-12-31 13F MERCK & CO. COM Put 75,000 6,135 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.