Grant Permission from another MCC or PCC account [0-3933000013694]

[an...@samcomtechnobrains.com]

We are implementing one product which can save time for managing some groups and campaign.

My question is we have get approved API from MCC account called "A"

My product is ready for account "A" . Now i want to launch this product for all user. so i guess lots of customer will use this service. and for that customer i need to implement something like then can login with google. 

For the manage their campaigns & Groups and Ads i need to grant Permission from MCC account "B" or PCC account "C" after that i can manage Ads or campaigns. but i don't want to link Account "B" & "C" to "A" .

 Can you please let me know if any API will solve my question or any other way to access & manage adword using login will google API .

Looking foreword from you 

Thanks

Ankit