Denying allegations that he stole a lucrative whistleblower client on his way out of Grant & Eisenhofer, former director Reuben Guttman on Tuesday accused the plaintiffs firm of rehashing old claims and using a recent breach-of-contract lawsuit to sully his reputation.

Represented by employment law boutique Outten & Golden, Guttman and his current firm, Washington, D.C.-based whistleblower boutique Guttman, Buschner & Brooks, filed several motions in response to a contract lawsuit Grant & Eisenhofer brought in August in D.C. federal court. The lawsuit seeks $7 million in damages, plus a share of a $280 million settlement in a False Claims Act whistleblower case in which drug company Celgene Corp. was accused of illegally promoting medications for off-label uses.