Jason Haddock - 12 Dec 2025 Form 4 Insider Report for Merus N.V. (MRUS)

Role: Director
Signature: /s/ Peter Silverman as attorney-in-fact
Issuer symbol: MRUS
Transactions as of: 12 Dec 2025
Transactions value $: $0
Form type: 4
Filing time: 12 Dec 2025, 19:02:22
Previous filing: 27 May 2025
SEC: View on sec.gov

Reporting Owners (1)

Name	Relationship	Address	Signature	Signature date	CIK
Haddock Jason	Director	C/O MERUS N.V., UPPSALALAAN 17, UTRECHT, NETHERLANDS	/s/ Peter Silverman as attorney-in-fact	12 Dec 2025	0001680628

Derivative Securities (e.g., puts, calls, warrants, options, convertible securities)

Type	Sym	Class	Transaction	Value $	Shares	Change %	* Price $	Shares After	Date	Underlying Class	Amount	Exercise Price	Ownership	Footnotes
transaction	MRUS	Share Option (right to buy)	Disposed to Issuer	$0	-13.2K	-100%	$0.00	0	12 Dec 2025	Common Shares	13.2K	$41.60	Direct	F1, F2
transaction	MRUS	Share Option (right to buy)	Disposed to Issuer	$0	-17.7K	-100%	$0.00	0	12 Dec 2025	Common Shares	17.7K	$48.73	Direct	F1, F2

* An asterisk sign (*) next to the price indicates that the price is likely invalid.

Jason Haddock is no longer subject to Section 16 filing requirements. Form 4 or Form 5 obligations may continue.

Explanation of Responses:

Id	Content
F1	On September 29, 2025, Merus N.V. (the "Issuer") entered into a transaction agreement (as it may be amended, supplemented or otherwise modified from time to time, the "Transaction Agreement") with Genmab A/S ("Genmab") and its wholly owned subsidiary, Genmab Holding II B.V. (the "Purchaser"). Pursuant to the terms of the Transaction Agreement, the Purchaser commenced a tender offer for all the issued and outstanding common shares, par value EUR 0.09 per share (the "Shares"), of the Issuer (the "Offer"), and, on December 12, 2025 (the "Acceptance Time"), the Purchaser accepted all of the Shares that were validly tendered and not properly withdrawn pursuant to the Offer as of the Acceptance Time in exchange for a cash payment equal to $97.00 per Share, without interest and less applicable withholding taxes (the "Offer Consideration"), which Offer Consideration will be paid as soon as practicable following the Acceptance Time.
F2	This option was cancelled pursuant to the Transaction Agreement in exchange for cash (without interest and net of applicable withholding tax and other applicable deductions) in an amount equal to the product of (i) the amount by which the Offer Consideration exceeds the applicable exercise price per Share of such option and (ii) the aggregate number of Shares underlying such option.

Content

On September 29, 2025, Merus N.V. (the "Issuer") entered into a transaction agreement (as it may be amended, supplemented or otherwise modified from time to time, the "Transaction Agreement") with Genmab A/S ("Genmab") and its wholly owned subsidiary, Genmab Holding II B.V. (the "Purchaser"). Pursuant to the terms of the Transaction Agreement, the Purchaser commenced a tender offer for all the issued and outstanding common shares, par value EUR 0.09 per share (the "Shares"), of the Issuer (the "Offer"), and, on December 12, 2025 (the "Acceptance Time"), the Purchaser accepted all of the Shares that were validly tendered and not properly withdrawn pursuant to the Offer as of the Acceptance Time in exchange for a cash payment equal to $97.00 per Share, without interest and less applicable withholding taxes (the "Offer Consideration"), which Offer Consideration will be paid as soon as practicable following the Acceptance Time.

This option was cancelled pursuant to the Transaction Agreement in exchange for cash (without interest and net of applicable withholding tax and other applicable deductions) in an amount equal to the product of (i) the amount by which the Offer Consideration exceeds the applicable exercise price per Share of such option and (ii) the aggregate number of Shares underlying such option.