Most people who work in software development have signed an Intellectual Property Rights Assignment notice whenever they start a new job. The purpose of these assignments is to ensure the employer obtains ownership of anything the employee creates which would either attract copyright, or be suitable for patenting.
Although they are meant to cover work done on the employer's behalf, they are nearly always written fairly broadly, effectively covering anything the employee creates during their period of employment (even when 'off duty').
The implication of this is that a contributor to your project, who submits their contributions under a CTA (Copyright Transfer Agreement) might not actually own the copyrights they are assigning to your project.
Is anyone aware of this having been tested in court, or of cases where this has caused problems?
Is it possible to craft a CTA to work around this issue?