A sign of Research in Motion (RIM) is seen at its headquarters in Waterloo, Ontario, January 22, 2012. - Photo by AFP

NEW YORK: The founders and CEOs of Canadian telecommunications company Research in Motion, Jim Balsillie and Mike Lazaridis, announced on Sunday that they were leaving their posts.

“In every successful company that's developed by founders,” Lazaridis said in a statement quoted by The New York Times, “there comes a time when it enters a new phase of growth and it's time for the founders to pass the baton to new management.”

BlackBerry maker Research in Motion's share of the US smartphone market declined during the three months ending in November, while Apple and Google's Android platform both made gains, according to industry tracker comScore.

The Waterloo, Ontario-based RIM saw its share of US smartphone subscribers fall to 16.6 percent at the end of November from 19.7 per cent at the end of August, according to comScore.

Android was the top smartphone platform with a 46.9 per cent share of the US market at the end of November, up from 43.8 per cent.

Apple's market share also rose during the period – by 1.4 percentage points to 28.7 per cent.

Microsoft, meanwhile, saw its share of the smartphone market fall to 5.2 per cent from 5.7 per cent.

RIM has been struggling in recent months and has been the subject of persistent takeover speculation.