(1) Plaintiffs. Persons may join in one action as plaintiffs if:
(A) they assert any right to relief jointly, severally, or in the alternative with respect to or arising out of the same transaction, occurrence, or series of transactions or occurrences; and
(B) any question of law or fact common to all plaintiffs will arise in the action.
(2) Defendants. Persons—as well as a vessel, cargo, or other property subject to admiralty process in rem—may be joined in one action as defendants if:
(A) any right to relief is asserted against them jointly, severally, or in the alternative with respect to or arising out of the same transaction, occurrence, or series of transactions or occurrences; and
(B) any question of law or fact common to all defendants will arise in the action.
(3) Extent of Relief. Neither a plaintiff nor a defendant need be interested in obtaining or defending against all the relief demanded. The court may grant judgment to one or more plaintiffs according to their rights, and against one or more defendants according to their liabilities.
(b) Protective Measures. The court may issue orders—including an order for separate trials—to protect a party against embarrassment, delay, expense, or other prejudice that arises from including a person against whom the party asserts no claim and who asserts no claim against the party.
(As amended Feb. 28, 1966, eff. July 1, 1966; Mar. 2, 1987, eff. Aug. 1, 1987; Apr. 30, 2007, eff. Dec. 1, 2007.)
Notes of Advisory Committee on Rules—1937
The provisions for joinder here stated are in substance the provisions found in England, California, Illinois, New Jersey, and New York. They represent only a moderate expansion of the present federal equity practice to cover both law and equity actions.
With this rule compare also [former] Equity Rules 26 (Joinder of Causes of Action), 37 (Parties Generally—Intervention), 40 (Nominal Parties), and 42 (Joint and Several Demands).
The provisions of this rule for the joinder of parties are subject to Rule 82 (Jurisdiction and Venue Unaffected).
Note to Subdivision (a). The first sentence is derived from English Rules Under the Judicature Act (The Annual Practice, 1937) O. 16, r. 1. Compare Calif.Code Civ.Proc. (Deering, 1937) §§378, 379a; Ill.Rev.Stat. (1937) ch. 110, §§147–148; N.J.Comp.Stat. (2 Cum.Supp., 1911–1924), N.Y.C.P.A. (1937) §§209, 211. The second sentence is derived from English Rules Under the Judicature Act (he Annual Practice, 1937) O. 16, r. 4. The third sentence is derived from O. 16, r. 5, and the fourth from O. 16, r.r. 1 and 4.
Note to Subdivision (b). This is derived from English Rules Under the Judicature Act (The Annual Practice, 1937) O. 16, r.r. 1 and 5.
Notes of Advisory Committee on Rules—1966 Amendment
See the amendment of Rule 18(a) and the Advisory Committee's Note thereto. It has been thought that a lack of clarity in the antecedent of the word “them,” as it appeared in two places in Rule 20(a), contributed to the view, taken by some courts, that this rule limited the joinder of claims in certain situations of permissive party joinder. Although the amendment of Rule 18(a) should make clear that this view is untenable, it has been considered advisable to amend Rule 20(a) to eliminate any ambiguity. See 2 Barron & Holtzoff, Federal Practice & Procedure 202 (Wright Ed. 1961).
A basic purpose of unification of admiralty and civil procedure is to reduce barriers to joinder; hence the reference to “any vessel,” etc.
Notes of Advisory Committee on Rules—1987 Amendment
The amendments are technical. No substantive change is intended.
Committee Notes on Rules—2007 Amendment
The language of Rule 20 has been amended as part of the general restyling of the Civil Rules to make them more easily understood and to make style and terminology consistent throughout the rules. These changes are intended to be stylistic only.