KeHE Distributors, LLC v. Killion

(1) Whether an employee's right to join a collective action under the Fair Labor Standards Act (FLSA) is waivable (as the Second, Third, Fourth, Fifth, Eighth, Ninth, and Eleventh Circuits have held) or non-waivable (as the Sixth Circuit held here); and (2) whether employees make "sales" within the meaning of the FLSA when they work entirely on commission based on orders that they "write and transmit" to replenish a customer's inventory, but do not singlehandedly cause sales volume to increase.