The Assistant Attorney General in charge of the Antitrust Division of the Department of Justice shall designate an antitrust investigator to serve as custodian of documentary material, answers to interrogatories, and transcripts of oral testimony received under this chapter, and such additional antitrust investigators as he shall determine from time to time to be necessary to serve as deputies to such officer.
Any person, upon whom any demand under section 1312 of this title for the production of documentary material has been duly served, shall make such material available for inspection and copying or reproduction to the custodian designated therein at the principal place of business of such person (or at such other place as such custodian and such person thereafter may agree and prescribe in writing or as the court may direct, pursuant to section 1314(d)  of this title) on the return date specified in such demand (or on such later date as such custodian may prescribe in writing). Such person may upon written agreement between such person and the custodian substitute copies for originals of all or any part of such material.
In the event of the death, disability, or separation from service in the Department of Justice of the custodian of any documentary material, answers to interrogatories, or transcripts of oral testimony produced under any demand issued pursuant to this chapter, or the official relief of such custodian from responsibility for the custody and control of such material, answers, or transcripts, the Assistant Attorney General in charge of the Antitrust Division shall promptly (1) designate another antitrust investigator to serve as custodian of such material, answers, or transcripts, and (2) transmit in writing to the person who produced such material, answers, or testimony notice as to the identity and address of the successor so designated. Any successor designated under this subsection shall have with regard to such material, answers, or transcripts all duties and responsibilities imposed by this chapter upon his predecessor in office with regard thereto, except that he shall not be held responsible for any default or dereliction which occurred prior to his designation.