Many issues arise when an officer or director involuntarily leaves a company. Companies are quick to enforce non-compete agreements and protect trade secrets against the former officer, but often do not consider protection of legal communications in which the officer participated.
A former officer inherently maintains insider information, including the contents of privileged emails and other communications that he created or 
But in post-departure litigation between the officer and the company, the question arises whether the corporation may prevent the use of privileged, officer-created communications or whether the privilege equally belongs to the former officer turned adversary.
In my recent article, What’s Mine is Not Yours: Former Officers and Directors and the Corporation’s Attorney-Client Privilege, co-written with Kristi Wilcox Arth, I discuss that courts take two approaches to this issue: the collective-corporate-client approach and the entity-as-client approach.  The approach a court takes will determine whether the corporation may prevent a former officer from using privileged communications.
This article, available here, was originally published in The Corporate Counselor, and I thank this publication for permission to reprint the article on my blog. The article was later re-published in The Association of Corporate Counsel Newsstand and Corporate Counsel.  And for a specific discussion of a court addressing these issues, see my prior post Who’s the Client? Former CEO Not Entitled to Company’s Privileged Documents.
I hope you find the article informative and helpful.