this is dependant on the working contract with the previous employer.

I work as a sysadmin, and I copy my code (small perl hacks and such) from employer to employer. this is my personal code toolbox, and I have to keep it, update it, and bring it with me.

I got a job offer from an ISP at one time, and they wanted me to sign a contract with a non-compete clause, and a ownership of code/ideas clause.. I wouldn't be able to work in the ISP industry for 2 years if i quit, and anything I did, at home or at work would belong to them.. as a sysadmin, I find this intolerable.. I told them to go take a flying leap.