What circumstances led to his expulsion or subjection are unknown; nothing is heard of him until his death in 302 BCE.
However, it appears that he had submitted to the Macedonian Antigonus, who, to prevent him from joining the league of Cassander and his confederates, arranged for his assassination in Cius.
Therefore, it is likely that he was the same Mithradates, son of Ariobarzanes prince of Cius, who is mentioned by Xenophon[5] as having betrayed his father, and the same circumstance is alluded to by Aristotle[6].
Neither is he the Mithridates mentioned by Xenophon[7] as satrap of Cappadocia and Lycaonia in the late 5th century BCE.
Between 362 and 337 BCE the family fiefdom of Cius in Mysia was held by Ariobarzanes II (possibly Mithridates' brother).