Fascinating. I've never thought of this. What is the law in the US? If I e-mail a friend during work hours (or write this comment during lunch), does my company own the rights to this?
If you were hired to do some work, the result is "work for hire" and the copyright resides in the company. If you write software, emails, etc unrelated to your job you would ordinarily retain copyright to those. Cases like the one in the story are rather ambiguous. That's employment agreements almost always elaborate on the topic, saying that, for instance, code you write on company computers or on company time belongs to the company.
If you were hired to do some work, the result is "work for hire" and the copyright resides in the company. If you write software, emails, etc unrelated to your job you would ordinarily retain copyright to those. Cases like the one in the story are rather ambiguous. That's employment agreements almost always elaborate on the topic, saying that, for instance, code you write on company computers or on company time belongs to the company.