"Do not author or modify product data"
Creating new data is the purview of the CAD software
"Do not create alternative repositories, especially outside firewall"
Data management & storage is the scope of PDM/PLM systems
"Consume product design data without sacrificing IP"
Respect sanctity of the design while giving access to widest audience in the enterprise
"Do not write back to PDM/PLM system"
Keeps enterprise systems secure and prevents corruption of data