The Abernathy MacGregor Group in New York is working with Comcast, while Kekst & Company is aiding Disney in its defence.
Abernathy chief operating officer Adam Miller, who confirmed that his firm is working with Comcast, said that it has worked with the cable operator since 1996, including on its takeover of AT&T Broadband in 2001.
Kekst is working with Disney, according to a source familiar with the deal. Both declined to comment.
As of last week, Disney rejected Comcast's unsolicited stock offer of about $50bn (£26.5bn), saying it was too low. There is speculation that Comcast’s next move might be to file a motion to ask shareholders to remove Disney’s board of directors.
Disney’s eagerly anticipated annual general meeting takes place on 3 March.