For each business that is owned by the same person, a different FEIN number is required to represent the business. A FEIN is unique to a business just like Social Security number is unique to an individual.
Additional meaning of Federal Employer Identification Number (FEIN):
Federal Employer Identification Number or (FEIN)) is the corporate equivalent to a Social Security Number, although it can be issued to anyone, including individuals, who have to pay withholding taxes on employees. FEIN or Federal Employer Identification Number is also known as Federal Tax Identification Number.