Multiple user in one customer id

[Mark Anthony Gutierrez]

Is it okay to use one client_customer_id to many users requesting at the same time?

[Sreelakshmi Sasidharan (AdWords API Team)]

Hi Mark, 

Same or different users can make parallel calls to the same account. However, if the number of calls issued against a single account exceeds a limit in a short duration of time, you will encounter rate limit error with ACCOUNT scope. To read more about rate limit errors please check this guide. If you encounter the rate limit error, you will need to wait for the time specified in retryAfterSeconds before you make any new API calls. It's recommended to set a reasonable upper bound for the total number of concurrent threads that are going to make requests (across all processes and machines), and adjust upward from there to optimize your throughput without exceeding the rate limit. You can find the best practices guide here. Let me know if you have any additional questions. 

Thanks,
Sreelakshmi, AdWords API Team