As of Release 4.0A, the material group is no longer stored at document item level but at individual service level.
A set of service specifications with several service lines can have a different material group in each such line.
This facilitates analyses by material group at service line level as of Release 4.0A.
In the case of services without master records, the valuation class for account determination is found on the basis of the material group at service level.
You can set a default value for the material group at item level among the default values for each purchasing organization or client. This makes document processing easier for the user.
For more on this topic, refer to the IMG documentation
Source determination and default values .