21 C.F.R. § 1303.26
The Administrator may at any time reduce an individual manufacturing quota for a basic class of controlled substance listed in Schedule I or II which he has previously fixed in order to prevent the aggregate of the individual manufacturing quotas and import permits outstanding or to be granted from exceeding the aggregate production quota which has been established for that class pursuant of § 1303.11 , as adjusted pursuant to § 1303.13 . If a quota assigned to a new manufacturer pursuant to § 1303.23(b) , or if a quota assigned to any manufacturer is increased pursuant to § 1303.24(c) , or if an import permit issued to an importer pursuant to part 1312 of this chapter, causes the total quantity of a basic class to be manufactured and imported during the year to exceed the aggregate production quota which has been established for that class pursuant to § 1303.11 , as adjusted pursuant to § 1303.13 , the Administrator may proportionately reduce the individual manufacturing quotas and import permits of all other registrants to keep the aggregate production quota within the limits originally established, or, alternatively, the Administrator may reduce the individual manufacturing quota of any registrant whose quota is suspended pursuant to § 1303.24(b) or § 1301.36 of this chapter, or is abandoned pursuant to § 1303.27 .
21 C.F.R. §1303.26