The Lead Investigator may enter into discussions with appropriate parties to address problems identified with the submission of evidence requested pursuant to Sec. 270.313 of this subpart. Should negotiations fail to result in the submission of such evidence, a subpoena may be issued pursuant to Sec. 270.315. [68 FR 4694, Jan. 30, 2003, as amended at 68 FR 24345, May 7, 2003]