One of the limitations of the federal family and medical leave act is that it only applies to those companies that have or more employees during 20 or more calendar work weeks in the current or preceding year

I believe the answer is: companies that have 50 or more employees

This limitation means that federal family and medical leave act wouldn't covered full time workers for small business that on average only have less than 7 employees and it also wouldn't covered employees that hired on freelance/contractual bassis.