Hi Orestis,
I wasn't able to find a Genesys resource that explicitly confirms licensing behaviour for OAuth clients, but based on the documentation available:
Client Credentials is designed for non-user applications and operates outside the context of a user, with access controlled by the roles assigned directly to the OAuth client.
https://help.mypurecloud.com/articles/create-an-oauth-client/
Because of that, my understanding is that the OAuth client itself does not behave like a named user consuming a license. Instead, access is governed by the permissions assigned, and your organisation still needs to be entitled to the underlying outbound functionality those permissions relate to.
For anything contract-specific around licensing, hopefully someone from community might add more to this. Following this post.
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Phaneendra
Technical Solutions Consultant
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