[castell]

Google Knowledge Graph is based on Freebase.com. Google shut it down, last month. IBM relied on Freebase for Watson, so they acquired Blekko last month, a real web search engine & knowledge base startup. Microsoft already owns Powerset company that powers their Cortana. Apple needs a up-to-date knowledge base too, currently they rely on WolframAlpha and Freebase, afaik.

Shutting down Freebase was a big hit for many projects in the AI space, Freebase had 2,903,361,537 facts in comparision Wikimedia's Wikidata has just 13,924,224 facts - that's still a huge difference.

http://en.wikipedia.org/wiki/Freebase , http://en.wikipedia.org/wiki/Knowledge_Graph , http://en.wikipedia.org/wiki/Blekko , http://en.wikipedia.org/wiki/Powerset_(company) , http://en.wikipedia.org/wiki/Knowledge_Vault , http://venturebeat.com/2015/03/27/ibm-acquires-web-crawling-...