Merus N.V.
US ˙ NasdaqGM ˙ NL0011606264
DETTE SYMBOL ER IKKE LÆNGERE AKTIVT

SecurityMRUS / Merus N.V.
InstitutionCitadel Advisors Llc
ManagerKen Griffin
Latest Disclosed Ownership0 shares
Latest Disclosed Value $ 0
Citadel Advisors Llc ownership in MRUS / Merus N.V.

On February 17, 2026 - Citadel Advisors Llc filed a 13F-HR form disclosing ownership of 0 shares of Merus N.V. (US:MRUS) valued at $0 USD as of December 31, 2025. The entity filed a previous 13F-HR on November 14, 2025 disclosing 614,538 shares of Merus N.V.. The current value of the position is $0 USD.

Citadel Advisors Llc has a history of taking positions in derivatives of the underlying security (MRUS) 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.

MRUS / Merus N.V. 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)
2026-02-17 2025-12-31 13F MERUS N V COM N5749R100 0 -100.00 0
2025-11-14 2025-09-30 13F MERUS N V COM N5749R100 614,538 278,944 83.12 57,859 227.77 0.0088
2025-08-14 2025-06-30 13F MERUS N V COM N5749R100 335,594 308,605 1,143.45 17,652 1,455.24 0.0031
2025-05-15 2025-03-31 13F MERUS N V COM N5749R100 26,989 18,886 233.07 1,136 233.82 0.0002
2025-02-14 2024-12-31 13F MERUS N V COM N5749R100 8,103 -211,116 -96.30 341 -96.90 0.0001
2024-11-14 2024-09-30 13F MERUS N V COM N5749R100 219,219 37,366 20.55 10,952 1.78 0.0021
2024-08-14 2024-06-30 13F MERUS N V COM N5749R100 181,853 -170,355 -48.37 10,760 -32.15 0.0022
2024-05-15 2024-03-31 13F MERUS N V COM N5749R100 352,208 71,957 25.68 15,860 105.80 0.0031
2024-02-14 2023-12-31 13F MERUS N V COM N5749R100 280,251 277,066 8,699.09 7,707 10,174.67 0.0015
2023-11-14 2023-09-30 13F MERUS N V COM N5749R100 3,185 -83,099 -96.31 75 -96.70 0.0000
2023-08-14 2023-06-30 13F MERUS N V COM N5749R100 86,284 -59,175 -40.68 2,272 -15.13 0.0005
2023-05-15 2023-03-31 13F MERUS N V COM N5749R100 145,459 87,533 151.11 2,676 198.66 0.0006
2023-02-14 2022-12-31 13F MERUS N V COM N5749R100 57,926 -7,845 -11.93 896 -31.97 0.0002
2022-11-14 2022-09-30 13F MERUS N V COM N5749R100 65,771 49,712 309.56 1,317 261.81 0.0003
2022-08-15 2022-06-30 13F MERUS N V COM N5749R100 16,059 -662,676 -97.63 364 -97.97 0.0001
2022-05-16 2022-03-31 13F MERUS N V COM N5749R100 678,735 81,393 13.63 17,946 -5.52 0.0037
2022-02-14 2021-12-31 13F MERUS N V COM N5749R100 597,342 419,152 235.23 18,995 384.57 0.0039
2021-11-15 2021-09-30 13F MERUS N V Cmn N5749R100 178,190 -35,446 -16.59 3,920 -12.91 0.0008
2021-08-16 2021-06-30 13F MERUS N V COM N5749R100 213,636 162,986 321.79 4,501 325.43 0.0010
2021-05-21 2021-03-31 13F/A-1 MERUS N V COM N5749R100 50,650 50,650 1,058 0.0003
2021-05-17 2021-03-31 13F MERUS N V COM N5749R100 50,650 50,650 1,058 0.0003
2020-11-16 2020-09-30 13F MERUS N V Cmn N5749R100 0 -20,565 -100.00 0 -100.00
2020-08-14 2020-06-30 13F MERUS N V Cmn N5749R100 20,565 20,565 331 0.0001
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
(%)
2026-02-17 2025-12-31 13F MERUS N V COM Call 0 -100.00 0 n/a n/a n/a
2025-11-14 2025-09-30 13F MERUS N V COM Call 76,000 25.83 7,155 125.21 n/a n/a n/a
2025-08-14 2025-06-30 13F MERUS N V COM Call 60,400 459.26 3,177 599.78 n/a n/a n/a
2025-05-15 2025-03-31 13F MERUS N V COM Call 10,800 120.41 455 120.39 n/a n/a n/a
2025-02-14 2024-12-31 13F MERUS N V COM Call 4,900 -78.97 206 -82.30 n/a n/a n/a
2024-11-14 2024-09-30 13F MERUS N V COM Call 23,300 -31.07 1,164 -41.77 n/a n/a n/a
2024-08-14 2024-06-30 13F MERUS N V COM Call 33,800 6.96 2,000 40.58 n/a n/a n/a
2024-05-15 2024-03-31 13F MERUS N V COM Call 31,600 3,060.00 1,423 5,166.67 n/a n/a n/a
2024-02-14 2023-12-31 13F MERUS N V COM Call 1,000 -76.74 28 -73.27 n/a n/a n/a
2023-11-14 2023-09-30 13F MERUS N V COM Call 4,300 -77.95 101 -80.31 n/a n/a n/a
2023-08-14 2023-06-30 13F MERUS N V COM Call 19,500 267.92 513 428.87 n/a n/a n/a
2023-05-15 2023-03-31 13F MERUS N V COM Call 5,300 -79.46 98 -75.69 n/a n/a n/a
2023-02-14 2022-12-31 13F MERUS N V COM Call 25,800 399 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
(%)
2026-02-17 2025-12-31 13F MERUS N V COM Put 0 -100.00 0 n/a n/a n/a
2025-11-14 2025-09-30 13F MERUS N V COM Put 30,700 -13.03 2,890 55.71 n/a n/a n/a
2025-08-14 2025-06-30 13F MERUS N V COM Put 35,300 263.92 1,857 354.90 n/a n/a n/a
2025-05-15 2025-03-31 13F MERUS N V COM Put 9,700 -42.94 408 -42.86 n/a n/a n/a
2025-02-14 2024-12-31 13F MERUS N V COM Put 17,000 -15.00 715 -28.53 n/a n/a n/a
2024-11-14 2024-09-30 13F MERUS N V COM Put 20,000 -34.21 999 -44.44 n/a n/a n/a
2024-08-14 2024-06-30 13F MERUS N V COM Put 30,400 4.11 1,799 36.83 n/a n/a n/a
2024-05-15 2024-03-31 13F MERUS N V COM Put 29,200 145.38 1,315 301.83 n/a n/a n/a
2024-02-14 2023-12-31 13F MERUS N V COM Put 11,900 -48.26 327 -39.67 n/a n/a n/a
2023-11-14 2023-09-30 13F MERUS N V COM Put 23,000 42.86 542 28.13 n/a n/a n/a
2023-08-14 2023-06-30 13F MERUS N V COM Put 16,100 -8.00 424 31.37 n/a n/a n/a
2023-05-15 2023-03-31 13F MERUS N V COM Put 17,500 430.30 322 531.37 n/a n/a n/a
2023-02-14 2022-12-31 13F MERUS N V COM Put 3,300 51 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.