Television footage showed Mourinho saying something, apparently in his native Portuguese, while at one point looking into a camera, as he headed towards the tunnel after the final whistle of the 3-2 comeback win over Newcastle on October 6.
But now the FA have opted to appeal the charge, meaning Mourinho could yet find himself in hot water.
Both sides will submit their evidence for the new commission to hear, although with the appeal hearing not scheduled until next week, Mourinho will be on the touchline for Sunday's Manchester derby at the Etihad Stadium.
Jose Mourinho could still face punishment after the FA appealed against the decision to clear him of an abusive language charge.
Mourinho had been under intense pressure heading into the Newcastle game at Old Trafford amid speculation he would be sacked as United had not won any of their four previous matches.
"The written reasons for that decision were published on Wednesday and the FA has chose to challenge the ruling, meaning Mourinho could still face punishment".
" In reply to the charge, JM served his own expert report from Simao Valente, an Assistant Professor at the University of Lisbon and an expert in the Portuguese language, including colloquialisms". His words were inaudible.
"Do you understand Italian?" said Mourinho.
Valente said that "the victory was vindication" and he did not consider the words used in the context to be abusive, insulting or improper. Thus, the objective person would have had to lip read JM's mouth and interpret Portuguese colloquialisms to accurately decipher the comments.
In this context, Mr Valente described that JM had just won a match which had been more hard than anticipated, after a hard start of the season in which he had been subjected to significant criticism in the media. Xavier said that he believed Mourinho twice said "Vós sois uns filhos da puta", which Xavier said translates to "sons of a whore" in English.