About GP12
Early Production Containment (GP12)
First, GP12 represents a level designation.
GP is the final inspection procedure before shipment for automotive parts manufacturers supplying General Motors. Its purpose is for the supplier to conduct a final inspection of products before warehousing from the customer's perspective.
GP10, GP11, and GP12 are not quality management methods, but rather abbreviations for quality management processes that General Motors (GM) uses for internal and supplier training. For example: GP4: General Procedure #4 - Supplier Submission of Material for Proc. Application.