Can you be open source and not open source?

“As an example, I was at a conference several years back when
Zimbra was first acquired by Yahoo and the head of Zimbra discussed
how about 99.5% of their code was written and maintained by the
employees of Zimbra and not the broader community. In fact, Zimbra
was not interested in having external parties submit code as their
development process was tightly managed and run via internal
processes. The source code was publically available to anyone
wishing to review or download it. Thus, I consider them an open
source project.”

Complete
Story