Haw. Rev. Stat. § 668-2
Subject to the rules of court and section 668-8.5, plaintiff shall join as a party every person having or claiming to have, as far as known to the plaintiff, any legal or equitable right, title, or interest in the property described in the complaint or any part thereof or any lien or other claim with respect thereto. Such persons shall be named in the complaint as far as known to the plaintiff.
All persons interested or who may claim any interest in the premises who cannot be identified or whose names are unknown to the plaintiff, shall be made parties as provided by the rules of court.
HRS § 668-2
Petition to partition equitable title allowed without joining trustees who held legal title under trust for execution of mortgage, since discharged. 10 H. 487. State not "person" having interest; no waiver of sovereign immunity.48 Haw. 92, 96,395 P.2d 620. Intervening minor.30 Haw. 323. Unborn heirs.31 Haw. 517. Cited:35 Haw. 262, 292.