This case illustrates the difference between legal malpractice claims and overbilling claims.  Ironicly, the defendant law firm concerntrates [specializes?] in legal malpractice litigation.

Gamiel v Curtis & Riess-Curtis, P.C. ,2007 NY Slip Op 07341 ,Decided on October 4, 2007
Appellate Division, First Department 

"Plaintiff’s affidavit was conclusory (see Murray Hill Invs. v Parker Chapin Flattau & Klimpl, 305 AD2d 228, 229 [2003]), and failed to set forth the requisite "but for" causation with respect to her legal malpractice claims (see Aquino v Kuczinski, Vila & Assoc., P.C., 39 AD3d 216, 218-219 [2007]), a deficiency not remedied by her attorney’s affirmation. However, we find that plaintiff sufficiently set forth the merit of her claims concerning overbilling and the withholding of her files to
preclude summary resolution of those claims (see Batra v Office Furniture Serv., 275 AD2d 229 [2000]). "