"[T]he Government is concerned about grand jury witnesses (or their attorneys) who disclose information to other grand jury witnesses (or their attorneys) with the purpose of obstructing the criminal investigation. The Government identifies joint defense agreements among attorneys as a threat to the integrity of the grand jury process. But denying witnesses access to their own transcripts to help prevent witnesses from talking to others makes little sense to begin with – and makes even less sense given that grand jury witnesses are under no legal obligation of secrecy. A grand jury witness is legally free to tell, for example, his or her attorney, family, friends, associates, reporters, or bloggers what happened in the grand jury. For that matter, the witness can stand on the courthouse steps and tell the public everything the witness was asked and answered. The secrecy rules therefore are no justification for denying witnesses access to their own transcripts."
via White Collar Crime Prof