I have noticed in different insurance requirements and other regulartions that 50 lives are needed for compliance. Is there anyplace where the definition of 50 lives is? Is it just full time employees or a combination of full, part, temporary etc?

Thanks for your help.

Based on what regulations you are talking about there can be varying definitions of "employee". For the most part insurance companies look at eligible employees as their definition of an employee. This could mean employees who work anywhere from 30 hours a week to 40 hours depending on the insurer.