Explained: 5 retired MLB umpires — including Joe West — sue benefit plan, alleging they are owed more money

Five retired MLB umpires sued their retirement plan and its retirement committee

ERISA

The Employee Retirement Income Security Act of 1974, a federal law governing retirement and benefit plans

Retirement committee

The body overseeing the umpires' retirement plan named as a defendant in the suit

Pretrial conference

A court hearing held before trial to address procedural matters