Art. 1037.Action Instituted Separately
Book II. Ordinary Proceedings · Title I. Pleading · Chapter 6. Incidental Actions · Enacted 1990 · no amendments on record · Last verified July 30, 2026
Full Text of Art. 1037
Amendment History
Acts 1990, No. 521, §2, eff. 1/1/1991.
Plain-English Summary
Most of the incidental-demand devices in this chapter are optional. If a defendant has a claim against the plaintiff and chooses not to raise it as a reconventional demand, Article 1037 says that choice doesn't cost the defendant the right to sue on that claim in a later, separate action. The same goes for claims that could have been raised as a cross-claim or third-party demand but weren't.
Two exceptions cut the other way. Article 1061 makes some reconventional demands compulsory — claims arising from the same transaction or occurrence as the principal demand generally have to be raised there or not at all. And Article 1113 imposes its own consequence when a defendant fails to bring in a third party who owed reimbursement, at least where the third party can show real prejudice from being left out.
The practical lesson is to check which of the two exceptions might apply before assuming a claim can wait. Most incidental demands are use-it-or-lose-nothing; a narrow but important set are use-it-or-lose-it.
Frequently Asked Questions
If a defendant doesn't file a reconventional demand, can the defendant still sue the plaintiff later?
Usually yes, under Article 1037's general rule. But if the claim is a compulsory reconventional demand under Article 1061 — one arising from the same transaction or occurrence as the principal demand — it has to be raised in the pending suit or it's lost.
Does failing to file a cross-claim or intervention forfeit the claim?
No. Article 1037's general rule preserves the right to bring the claim separately later, since cross-claims and interventions aren't subject to the compulsory exception that applies to some reconventional demands.
What happens if a defendant doesn't bring in a third party who owes reimbursement?
Article 1113 controls that situation specifically. The defendant generally keeps the right to sue the third party later, unless the third party can show it had a defense it lost the chance to use because it wasn't brought into the case.