A Florida man accused of running an unlicensed bitcoin exchange and who is among five defendants linked to last summer’s massive data breach at JPMorgan Chase & Co is in talks to resolve his criminal case, according to court papers filed Friday. Eun Young Choi, a prosecutor under Manhattan U.S. Attorney Preet Bharara who made the submission, said negotiations were not yet complete and sought an extension until Sept. 28 for when a grand jury would need to indict Lebedev. Mark Bernett, Lebedev’s lawyer, did not respond to requests for comment.