U.S. Court of Appeals for the Tenth Circuit

Niederer v. LPL Financial

September 8, 2026

Summary

The Tenth Circuit affirmed the district court’s dismissal of Niederer’s federal complaint. The court held that his §1983 claim failed because LPL is a private party, and that his remaining claims were barred by claim preclusion based on the arbitration award confirmed by a Wyoming court. The court also affirmed that the district court lacked jurisdiction to consider post‑appeal motions.