Threadneedle head of marketing Dennis Tumbult confirmed that Moore, who could not be reached for comment, had left the company. Tumbult declined to comment further.
He added that Threadneedle planned to hire a replacement for Moore and expand its three-strong comms team.
Tumbult is taking full control of Threadneedle's PR and marketing in anticipation of the departure of director of marketing Richard Eats, who is to retire in the next 18 months after ten years with the fund manager.
Eats has taken the role of acting head of comms until Threadneedle finds a replacement for Moore.