He was selected for an FAA-mandated random drug test, to be performed by a company called LabCorp. Pasternack arrived at the testing site, provided urine, but LabCorp told him that he hadn’t provided enough and had to wait. Pasternack was supposed to see a patient soon, though, so he asked whether he could leave and come back. There was no objection. Pasternack left, returned three hours later, and provided a urine sample that tested negative. Later, though, LabCorp determined that when Pasternack left to see a patient, it counted as a “refusal to test.”