A savvy webmaster was curious when he noticed that BingBot was crawling his site from Google IP addresses. Did Google acquire Bing's crawler? Was it some sort of fake bot trying to rip off content?
The question was brought up at Stack Exchange:
As it shows, user-agent shows it is bingbot. But whois data of IP address(126.96.36.199 and 188.8.131.52) shows it is from google servers.
So is it Google,Bing or any other content scrappers?
John Mueller of Google responded saying both! It was BingBot crawling a URL through Google's PageSpeed tool. John explained:
I double-checked with the team about these requests, and they appear to be for the PageSpeed service, which can act as a cache/proxy for websites. If search engines - like Bing or Google - crawl URLs like that, the service will forward those requests to your website when needed. That can make it look like these requests are coming from Google IP addresses, even though they initially originated elsewhere.
Forum discussion at Stack Exchange.