Reuters reports that Tyler Lessard, RIM’s senior vice-president for global alliances and developer relations, left the company. He’s just the latest in a long line of people that are abandoning RIM.

Mike Kirkup, a director of developer relations, resigned in August. RIM’s head of marketing, Keith Pardy, left in March, just ahead of the PlayBook launch, and two of his staff later exited for jobs with Samsung, a fierce rival whose phones and tablets use Google’s Android.