[reply to a deleted comment] That's a nice method of cooperation with a search engine, but in the majority of the cases (Reddit upvotes, Facebook likes, Twitte

[reply to a deleted comment] That's a nice method of cooperation with a search engine, but in the majority of the cases (Reddit upvotes, Facebook likes, Twitter followers) it's not implemented. A related question is if Google uses APIs or other external databases to get more semantically useful data? And if they use things like an Twitter API, do they have specific agreements with the sites? Or maybe they are not doing it in full agreement with TOS-es?