While making AdWords API calls, a common task that you have to perform as a developer is to ensure that the SOAP requests you make to the server are valid. This includes validation in terms of parameters required for an API call, as well as ensuring that your ads and criteria are in accordance with Adwords policies. AdWords API v200909 introduces a new RequestHeader field named validateOnly to help you validate your API calls. While making an API call in AdWords API v200909,