N.Y. Civil Practice Law & Rules § 1002: Permissive joinder of parties

§ 1002. Permissive joinder of parties. (a) Plaintiffs. Persons who

assert any right to relief jointly, severally, or in the alternative

arising out of the same transaction, occurrence, or series of

transactions or occurrences, may join in one action as plaintiffs if any

common question of law or fact would arise.

(b) Defendants. Persons against whom there is asserted any right to

relief jointly, severally, or in the alternative, arising out of the

same transaction, occurrence, or series of transactions or occurrences,

may be joined in one action as defendants if any common question of law

or fact would arise.

(c) Separate relief; separate trials. It shall not be necessary that

each plaintiff be interested in obtaining, or each defendant be

interested in defending against, all the relief demanded or as to every

claim included in an action; but the court may make such orders as will

prevent a party from being embarrassed, delayed, or put to expense by

the inclusion of a party against whom he asserts no claim and, who

asserts no claim against him, and may order separate trials or make

other orders to prevent prejudice.