2009 California Code of Civil Procedure - Section 872.510-872.550 :: Article 4. Parties

872.510.  The plaintiff shall join as defendants in the action all
persons having or claiming interests of record or actually known to
the plaintiff or reasonably apparent from an inspection of the
property, in the estate as to which partition is sought.

872.520.  (a) If the name of a person described in Section 872.510
is not known to the plaintiff, the plaintiff shall so state in the
complaint and shall name as parties all persons unknown in the manner
provided in Section 872.550.
   (b) If the ownership or the share or quantity of the interest of a
person described in Section 872.510 is unknown, uncertain, or
contingent, the plaintiff shall so state in the complaint. If the
lack of knowledge, uncertainty, or contingency is caused by a
transfer to an unborn or unascertained person or class member, or by
a transfer in the form of a contingent remainder, vested remainder
subject to defeasance, executory interest, or similar disposition,
the plaintiff shall also state in the complaint, so far as is known
to the plaintiff, the name, age, and legal disability (if any) of the
person in being who would be entitled to ownership of the interest
had the contingency upon which the right of such person depends
occurred prior to the commencement of the action.
   (c) The court shall upon its own motion or upon motion of any
party make such orders for joinder of additional parties and for
appointment of guardians ad litem pursuant to Sections 372, 373, and
373.5 as are necessary or proper.

872.530.  (a) If a person described in Section 872.510 is dead and
the plaintiff knows of a personal representative, the plaintiff shall
join such personal representative as a defendant.
   (b) If a person described in Section 872.510 is dead, or is
believed by the plaintiff to be dead, and the plaintiff knows of no
personal representative:
   (1) The plaintiff shall state these facts in an affidavit filed
with the complaint.
   (2) Where it is stated in the affidavit that such person is dead,
the plaintiff may join as defendants "the testate and intestate
successors of ____ (naming such deceased person), deceased, and all
persons claiming by, through, or under said decedent," naming them in
that manner.
   (3) Where it is stated in the affidavit that such person is
believed to be dead, the plaintiff may join such person as a
defendant, and he may also join "the testate and intestate successors
of ____ (naming such person) believed to be deceased, and all
persons claiming by, through, or under such person," naming them in
that manner.

872.540.  Where property is subject to a lease, community lease,
unit agreement, or other pooling arrangement with respect to oil or
gas or both, the plaintiff need not join as defendants persons whose
only interest in the property is that of a lessee, royalty-owner,
lessor-owner of other real property in the community, unit, or pooled
area, or working interest owner, or persons claiming under them, and
the judgment shall not affect the interests of such persons not
joined as defendants.

872.550.  Where partition is sought as to all interests in the
property, the plaintiff may join as defendants "all persons unknown
claiming any interest in the property," naming them in that manner.