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Pro Se 11

Third Party Complaint

Federal · United States Courts · Effective December 1, 2016

This form is a Third-Party Complaint used in federal court to file a complaint against a third person. It asks the court to consider the relationship between the filer and the third-party defendant, and why the third-party defendant should be responsible for any money awarded to the original plaintiff.

Open the official PDFfrom United States Courts

Where this fits in a case

Start a case

Stage: Start a case

This form is used when a party involved in a lawsuit wants to bring a new claim against a third person who was not part of the original lawsuit.

Either party may file.

Common questions

Who fills out this form?
This form is for a party who is representing themselves (pro se) to file a complaint against a third party.
What information does it ask for?
It asks for details about the original plaintiff, the defendant/third-party plaintiff, and the third-party defendant, including addresses and contact information.
Does it require legal arguments?
Yes, the form requires the filer to describe the relationship with the third-party defendant and explain why that person should be responsible for damages.

Revision history

No changes recorded since we started tracking this form on October 9, 2026. The current version took effect December 1, 2016.

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