Packer means any person who, within the area, stems, sorts, cleans, or seeds raisins, grades stemmed raisins, or packages raisins for market as raisins: Provided, That:

(a) No producer with respect to the raisins produced by him, and no group of producers with respect to raisins produced by the producers comprising the group, and not otherwise a packer, shall be deemed a packer if he or it sorts or cleans (with or without water) such raisins in their unstemmed form;

(b) Any dehydrator shall be deemed to be a packer, with respect to raisins dehydrated by him, only if he stems, cleans with water subsequent to such dehydration, seeds or packages them for market as raisin;

(c) The Committee may, with the approval of the Secretary restrict the exceptions as to permitted cleaning if necessary to cause delivery of sound raisins; and

(d) No person shall be deemed a packer by reason of the fact he repackages for market (with or without additional preparation) packed raisins which, in the hands of a previous holder, have been inspected and certified as meeting the applicable minimum grade standards for packed raisins.