What are the product MPN and Brand Fields?
The product MPN and Brand are unique identifiers used for Google Product Search. Google now requires a unique identifier for all products (except custom made items), which you can read more about here: http://support.google.com/merchants/bin/answer.py?hl=en&answer=160161
The table below shows you which unique identifiers you need to use for your product types.
|Category||Identifiers required for each product|
|Media (i.e., Music, Movies, Video games)||UPC, EAN, or JAN|
|Books||ISBN (Either ISBN-10 or ISBN-13. Exceptions apply for books published before 1970.)|
|Custom made goods||No identifiers are required at the moment|
At least two of the following three identifiers: