Impleader
Impleader: Bringing a third party into a lawsuit because that party may be liable for some or all of the claim. Also called a third-party complaint.

What impleader means
In practice, you will see impleader in pleadings, motions, orders and court rules. The definition above explains the general meaning. Even so, the meaning can shift with context. Therefore, always read it alongside the rule or document where it appears.
Where impleader comes up
For example, the term appears in these procedures:
- Third-Party Complaint (Impleader) (Fed. R. Civ. P. 14(a)): a defending party brings in a nonparty who is or may be liable to it for all or part of the claim against it.
How to research the term
Start with the primary source. For example, if impleader appears in a federal rule, read the rule itself and its official notes. After that, check your court’s local rules and any standing orders from the judge. In addition, search recent decisions from your own state or federal district. They show how courts read impleader in practice. Because state rules often differ, our state procedures guide links to each state’s official rules. Above all, make sure the version you read is still in force.
You can read the official rule text online for free.
Related legal terms
- Holder: under UCC § 1-201(b)(21)(A), the person in possession of a negotiable instrument payable to bearer or to that identified person.
- Holder in due course: a holder who took a negotiable instrument for value, in good faith and without notice of listed problems, and so takes free of many defenses.
- In forma pauperis: proceeding without prepaying court fees because of inability to pay.
- In propria persona: latin for "in one's own person." Appearing in court for yourself, without an attorney. Also called pro per or pro se.
Why precise terms matter
Courts read legal terms closely. As a result, knowing the exact meaning of a word helps you follow orders, rules and filings. Each glossary entry on Lawtopolis is short on purpose and links to the pages where the term is used.
Sources
Sources last reviewed: 2026-10-23
Lawtopolis provides legal information and education, not legal advice. Using this site does not create an attorney-client relationship. Laws and court rules vary by jurisdiction and change over time; verify every authority against the official source and consult a licensed attorney in your jurisdiction about your situation.
