Extract taken from Whitepaper "10 Reasons for Transitioning to CATIA V6" by TECHNIA's 3DEXPERIENCE/V6 Specialist Technical Team
Typically a PLM system will allow you to create a separate BOM tree from the CATIA structure with the BOM manager overseeing the reconfiguration of this BOM to the real purchased BOM. However they are often using only attributes about the parts, like part number and description, to work with. The 3DEXPERIENCE platform has numerous advantages here:
In many industries, it is often the case that assemblies are not merely the sum of their parts. Various operations are only performed after the parts have been assembled (drilling new holes, grinding down faces etc.) In most CAD systems, CATIA V5 included, it is awkward to represent both how the parts are made individually whilst also showing the finished assembly. This usually involves creating a “Phantom” part to represent the finished assembly. This is improved in V6 where geometry can be inserted directly against the assembly, with a special function called “Derived Representation” which copies all the required geometry of the assembly into one representation. This allows the post-assembly operations to be specified without needing to take out dummy part numbers.
Similarly, the ability to insert geometry directly against assemblies removes the need to create “Skeleton” parts to contain construction geometry for assemblies (patterns, package boundaries, centrelines etc.)