A collection code is a client-specific 7-digit alphanumeric code that helps Google identify which books belong in which client's account.
Please note that if your client has multiple imprints or templates under one account, each imprint or template has a separate collection code. The collection code can be found by going to your Service Provider Partner Center and following these steps:
- Sign in to the Partner Center at: play.google.com/books/publish.
- Select your client's account.
- Go to the Book Catalog.
- Click the Advanced button and select Manage templates.
- Look for the 7-digit alphanumeric collection code next to the template name.
If you don't yet have access to your client's account and need their collection code, ask them to follow the above steps. (They can skip the second step, where they select a specific account.)