21 CFR §507.120

1. (a)The receiving facility must approve suppliers in accordance with the requirements of § 507.110(d), and document that approval, before receiving raw materials and other ingredients received from those suppliers;
2. (b)
   1. (1)Written procedures for receiving raw materials and other ingredients must be established and followed;
   2. (2)The written procedures for receiving raw materials and other ingredients must ensure that raw materials and other ingredients are received only from approved suppliers (or, when necessary and appropriate, on a temporary basis from unapproved suppliers whose raw materials or other ingredients are subjected to adequate verification activities before acceptance for use); and
   3. (3)Use of the written procedures for receiving raw materials and other ingredients must be documented.