CPLR 321(a)
Boente v Peter C. Kurth Off. of Architecture & Planning, P.C., 2014 NY Slip Op 00473 [2nd Dept. 2014]
As the plaintiff correctly contends, the Supreme Court erred in accepting an untimely, pro se answer from the defendant corporation, and in thereby denying that branch of the plaintiff's motion which was for leave to enter a default judgment on the complaint. The proffered answer was a nullity, since a corporation must be represented by an attorney and cannot proceed pro se (see CPLR 321[a]; Pisciotta v Lifestyle Designs, Inc., 62 AD3d 850, 853; Bilello v Genesis Seafood, Inc., 12 AD3d 474; World On Columbus v L.C.K. Rest. Group, 260 AD2d 323, 324).
Emphasis mine
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