v3.25.4

Cover	Feb. 23, 2026
Document Type	8-K
Amendment Flag	false
Document Period End Date	Feb. 23, 2026
Entity File Number	001-43119
Entity Registrant Name	HCM IV Acquisition Corp.
Entity Central Index Key	0002089982
Entity Tax Identification Number	98-1883478
Entity Incorporation, State or Country Code	E9
Entity Address, Address Line One	85 Washington St
Entity Address, Address Line Two	1F
Entity Address, City or Town	Stamford
Entity Address, State or Province	CT
Entity Address, Postal Zip Code	06854
City Area Code	203
Local Phone Number	930-2200
Written Communications	false
Soliciting Material	false
Pre-commencement Tender Offer	false
Pre-commencement Issuer Tender Offer	false
Entity Emerging Growth Company	true
Elected Not To Use the Extended Transition Period	false
Units, each consisting of one Class A ordinary share and one-fourth of one Redeemable Warrant
Title of 12(b) Security	Units, each consisting of one Class A ordinary share and one-fourth of one Redeemable Warrant
Trading Symbol	HACQU
Security Exchange Name	NASDAQ
Class A Ordinary Shares, par value $0.0001 per share
Title of 12(b) Security	Class A Ordinary Shares, par value $0.0001 per share
Trading Symbol	HACQ
Security Exchange Name	NASDAQ
Redeemable Warrants, each whole warrant exercisable for one Class ordinary share at a price of $11.50 per share
Title of 12(b) Security	Redeemable Warrants, each whole warrant exercisable for one Class ordinary share at a price of $11.50 per share
Trading Symbol	HACQW
Security Exchange Name	NASDAQ

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Commission file number. The field allows up to 17 characters. The prefix may contain 1-3 digits, the sequence number may contain 1-8 digits, the optional suffix may contain 1-4 characters, and the fields are separated with a hyphen.

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Boolean flag that is true when the Form 8-K filing is intended to satisfy the filing obligation of the registrant as written communications pursuant to Rule 425 under the Securities Act.

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HCM IV Acquisition Corp. 8-K