Short answer. Yes, with the court's permission. Section 9 of Rule 11 lets a counterclaim or cross-claim that matured or was acquired after the answer was served be presented, by supplemental pleading before judgment, if the court allows it, rather than leaving that later-arising claim to be pursued only in a separate lawsuit.
What the law says
A counterclaim or a cross-claim which either matured or was acquired by a party after serving his or her pleading may, with the permission of the court, be presented as a counterclaim or a cross-claim by supplemental pleading before judgment.
Rule 11, Section 9 — Counterclaim or cross. Read the full provision →
The scenario this section addresses
Section 9 covers claims that did not yet exist, or that the party did not yet hold, at the time their answer was filed — a claim that either matured or was acquired by a party after serving his or her pleading. This is the counterpart to the preceding section, which requires an already-existing compulsory counterclaim or cross-claim to be included in the answer itself; this section handles the case where the claim simply wasn't ripe yet at that point. This does not cover claims that already existed and were simply overlooked when the answer was filed; a compulsory counterclaim the party already held at that time falls under the preceding section's stricter rule, not this one, and an omission there is not cured by treating the claim as newly matured.
How such a claim gets into the case
Rather than requiring — or even allowing — an amendment to the already-filed answer, Section 9 specifies that such a claim may be presented as a counterclaim or a cross-claim by supplemental pleading before judgment. This uses the supplemental pleading mechanism (addressed generally in Rule 10) specifically for claims that arose or matured after the answer was already on file. This mechanism binds the party seeking to add the claim to file the supplemental pleading itself, not simply announce the new claim informally in a motion or during a hearing; without an actual supplemental pleading presenting it, the newly matured or acquired claim does not become part of the case.
Permission of the court is required, and there's a deadline
This is not an automatic right — Section 9 conditions it on the permission of the court, echoing the general requirement for supplemental pleadings elsewhere in the Rules. There is also a firm outer limit: the supplemental pleading presenting the claim must come before judgment. A defendant who discovers a newly matured or acquired claim against the plaintiff needs to act while the case is still pending, not after judgment has already been rendered.
Related provisions
- Rule 11, Section 9 — Counterclaim or cross
- Rule 11, Section 8 — Existing counterclaim or cross
- Rule 11, Section 10 — Omitted counterclaim or cross