Hartley, 25, was cited following an alleged incident in the first half of England's 30-9 RBS 6 Nations victory over Ireland at Twickenham last Saturday.
The Northampton hooker remains suspended until he appears before the independent Six Nations disciplinary committee, which will be chaired by Roger Morris.
A biting offence carries a low-end entry point of a 12-week suspension, with 18 weeks for mid-range and 24-plus weeks at the top end in the International Rugby Board's disciplinary sanctions table.
If Hartley is banned, he could be ruled out of England's three-Test tour to South Africa in June.
Match referee Nigel Owens did not see the alleged incident, but the Welsh official told the two captains - England's Chris Robshaw and Ireland's Rory Best - that he had received "an accusation of biting" and had seen "a clear mark on the finger".
Robshaw insisted after the game that he had not seen anything untoward on the pitch.
Asked how he would react if one of England's players had bitten an opponent, Robshaw said: "It is one of those things we will have to address when we meet up, but at the moment it is innocent until proven guilty, so to speak.
"We will see what happens."