8.06—Investigations.
(a)
Each exchange shall establish and maintain a disciplinary procedure which requires the enforcement staff of the exchange to conduct investigations of possible rule violations within the disciplinary jurisdiction of the exchange. Such an investigation shall be commenced:
(2)
Upon the discovery or receipt of information by the exchange which, in the judgment of the enforcement staff, indicates a possible basis for finding that a violation has occurred or will occur.
(b)
Each enforcement staff investigation shall be completed within four months, unless there exists significant reason to extend it beyond such period. If for any reason the enforcement staff closes an investigation before determining whether a reasonable basis exists for finding that a violation has occurred, the staff shall fully set forth the reasons for so closing the investigation in its report.