Pursuant to CPLR 3116(a), a plaintiff's unsigned deposition transcript
may be used as though fully signed, where defendant submitted proof that
the certified transcript was provided to plaintiff's attorneys for execution and
not returned. An unsigned but certified transcript may be used as an admission, especially where there is no dispute as to the transcript's accuracy.
Luna v. CEC Entertainment, Inc., NY Slip Op 01429 (1st Dep't March 6, 2018)
Here is the decision.