profit from, profit off, profit off of

These are the three variations that can be found to express the concept that someone is making money out of something or someone.  The most acceptable of these is profit from which is listed in the OED and which is evidenced in Google Ngram.  Profit off draws a blank in both those language resources, but it undoubtedly has currency. As is often the way, when there are two lexical items meaning the same thing we try to draw a distinction between them. In this case it is being argued that profit from is neutral in tone, whereas profit off implies that the profitable activity is exploitative.  The verb profit off has negative connotations.

 Profit off of is the least acceptable with off of having the force of from. It is common enough in speech so a problem arises with reported speech in the media. If Donald Trump Jnr says that he did not profit off of the Trump presidency, then that is what must appear in media texts.  This allows us all to hear and read profit off of more frequently than we used to, and perhaps to drift into some kind of acceptance of it. It is a clumsy construction made even worse when another preposition follows it as in Solutions others can profit off of for free.  Note that I say clumsy rather thanincorrect, because the construction does have a long history in British English, becoming colloquial and nonstandard in later use. Yes, Shakespeare did say ‘A fall off of a tree’.  And American English has carried it comfortably as well.   ‘Take the cup off of the shelf’ would pass without notice in that variety of English. 

 I’m prepared to accept the distinction between profit from and profit off, contrived though I suspect it to be. I am not happy with profit off of.