When working with instances of an object, you can assign Color Per Vertex data to instances separately from their source. This allows you to create shared CPV data across all instances based on an existing instance, assign different CPV data to all instances.
To create shared Color Per Vertex data per instance
The painted colors appear on all instances of the object (including the source).
To create unshared Color Per Vertex data per instance
The painted colors appear on all instances of the object (including the source).
Each instance you create a new unshared color set for, is colored differently. If you rename one of these unshared color sets, the corresponding unshared color sets on other instances are renamed accordingly.
It is highly recommended that you rename unshared color sets since they can become very difficult to manage with default names.