A third-party complaint — the mechanism is often called impleader — lets an existing defendant bring an entirely new party into the case, asserting that this new party (the third-party defendant) is or may be liable to the original defendant for all or part of what the original defendant might owe the plaintiff. Classic examples include a defendant impleading an insurer that may owe coverage, a subcontractor a general contractor blames for the defect, or a manufacturer a retailer blames for a defective product.

Impleader is procedurally distinct from a cross-claim or counterclaim because it adds a party who was not previously in the case at all. Courts generally require the third-party claim to be derivative — tied to the original claim through indemnification, contribution, or subrogation — rather than an independent dispute the defendant happens to also have with someone else.

Juricratic represents an impleaded third-party defendant as a new party node connected to the matter through the specific derivative theory (indemnification, contribution) that justifies bringing them in, so a simulated run can show how bringing in — or not bringing in — that third party redistributes exposure across all the parties actually at the table.

Defense counsel use a third-party complaint to pull in an insurer, subcontractor, co-obligor, or upstream supplier who should ultimately bear some or all of the liability, rather than paying a judgment and then having to file a separate reimbursement lawsuit later. It consolidates related liability questions into one proceeding, which usually saves cost and avoids inconsistent outcomes across separate cases.