I have to assume that there is also a policy to prevent firing them as soon as they get back from leave, or else the whole thing is useless. I also have to ass

I have to assume that there is also a policy to prevent firing them as soon as they get back from leave, or else the whole thing is useless. I also have to assume that a replacement hired has the same rights as the employee who took leave. So there could be successive waves of sabbaticals. This policy would instantly destroy Silicon Valley. I can picture companies with more employees on leave to start startups than actual working employees of the company!