Google has began enforcing their API policy to prevent automated access to their search results. Google’s adWords API has been used by a variety of search engine tools to help marketers research search phrases and other activities.
As seen in the post below Google has prevented WordStream from publishing their data showing CPC rates for a variety of industries. Other major SEO tool providers have been impacted by the new enforcement. RavenSEOtools is shutting down their rank tracking features to maintain their AdWords API.
Early last year Google revoked wide spread access to the AdWords API in apparently the first step of restricting access.
It’s hard to say what this enforcement means. It could be simply maintaining the API required a lot of resource and cost. Or it may be the sign of more changes to come from Google. Preventing scraping of the search results will make it more difficult for the SEO industry to evaluate the impact of future algorithmic changes.
Google maintains the recent crack down on tool providers is nothing new as their Terms of Service have not been changed.
Read more about the latest at Search Engine Land