[Code of Federal Regulations] [Title 21, Volume 2] [Revised as of April 1, 2008] From the U.S. Government Printing Office via GPO Access [CITE: 21CFR111.135] [Page 245] TITLE 21--FOOD AND DRUGS CHAPTER I--FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) PART 111_CURRENT GOOD MANUFACTURING PRACTICE IN MANUFACTURING, PACKAGING, LABELING, OR HOLDING OPERATIONS FOR DIETARY SUPPLEMENTS--Table of Contents Subpart F_Production and Process Control System: Requirements for Quality Control Sec. 111.135 What quality control operations are required for product complaints? Quality control operations for product complaints must include reviewing and approving decisions about whether to investigate a product complaint and reviewing and approving the findings and followup action of any investigation performed.