Rogers & Wells partner Kevin Arquit is a man who might know a thing or twoabout ghosts.

Seven years ago, as the zealous director of the Federal Trade Commission’sBureau of Competition, Arquit helped conjure up a novel legal stratagem.Now, as the zealous lead counsel for generic drug maker Mylan LaboratoriesInc., he has found his past returning to haunt him. Citing Arquit’shandiwork, the FTC is trying to collect $120 million from his client in asuit filed in D.C. federal court.