Olympus said on Monday it was preparing to file its July-September earnings by December 14, a necessary step for the disgraced 92-year-old firm to remain listed.

The company also said it would hold a briefing on December 15 to explain the results after admitting to a $1.7 billion scheme to hide investment losses stretching back more than a decade.

The scandal has put the future of the 92-year-old maker of cameras and endoscopes at risk. Even if the company meets the earnings deadline, the Tokyo Stock Exchange can still decide to delist Olympus depending on the scale of its past misreportings.

Ousted CEO, British-born Michael Woodford, who blew the whistle on the scheme, arrives in Tokyo this week on a mission to persuade employees and shareholders he is the right person to get the company back on track.

But he faces a battle with current management, who want to pick their own successors.

(Reporting by Isabel Reynolds; Editing by Edwina Gibbs)