In one sentenceRule 40 lets plaintiffs join together, or defendants be joined, when their claims arise from the same transaction or occurrence and share a common question of law or fact.
(a)Permissive Joinder. All persons may join in one action as plaintiffs if they assert any right to relief jointly, severally, or in the alternative in respect of or arising out of the same transaction, occurrence, or series of transactions or occurrences and if any question of law or fact common to all of them will arise in the action. All persons may be joined in one action as defendants if there is asserted against them jointly, severally, or in the alternative any right to relief in respect of or arising out of the same transaction, occurrence, or series of transactions or occurrences and if any question of law or fact common to all of them will arise in the action. A plaintiff or defendant need not be interested in obtaining or defending against all the relief demanded. Judgment may be given for one or more of the plaintiffs according to their respective rights to relief, and against one or more defendants according to their respective liabilities.
(b)Separate Trials. 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 delay or prejudice.
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Plain-English Summary
Rule 40 sets when parties may be grouped in one suit by choice. Plaintiffs may join as plaintiffs, and defendants may be joined as defendants, when the claims arise out of the same transaction, occurrence, or series of them and share a common question of law or fact. A party need not have a stake in all of the relief sought.
To keep joinder fair, the court may order separate trials or enter other orders so that a party is not embarrassed, delayed, or burdened by being grouped with a claim that has nothing to do with it.
Frequently Asked Questions
When can plaintiffs join in one Texas lawsuit?
When their claims arise out of the same transaction, occurrence, or series of them and share a common question of law or fact, under Rule 40.
Can the court split joined claims for trial?
Yes. Under Rule 40, the court may order separate trials or other protective orders to prevent prejudice, delay, or expense.
Source & verification. Rule text and the official Notes and Comments are reproduced verbatim from the
Texas Rules of Civil Procedure (Tex. R. Civ. P. 40), published by the Texas Judicial Branch (txcourts.gov).
Promulgated by the Supreme Court of Texas. The plain-English summary is original and draws on official sources. Last verified June 28, 2026. ·
Official source
Also known as:permissive joinder of partiesjoinder of partiessame transaction or occurrencecommon questionTRCP 40