Is Academia.edu's "mentions" feature real?
It is so clearly a hoax, trying to get more subscribers. Please, Academia.edu software engineers, do not try the "we make errors" card, as it is not believable. 

I do believe they are legit, but this mentions baiting reeks of dark patterns. If they continue doing this, they will lose credibility with the public, and end up losing the one thing people are willing to pay for, especially in research: a trusted reputation.