The Department of Veterans Affairs also has a database of veteran-owned businesses that is used. It was developed to support federal agencies and private businesses who want to find veteran-owned businesses and to support veteran-owned businesses who want an easier way to market to all potential federal customers.
When registering in the VIP database, your veteran status is automatically verified by Veterans Affairs. You will be designated as a veteran-owned small business (VOSB) or a service-disabled veteran-owned small business (SDVOSB). In both cases, the veteran must own not less than 51% of the business (or, in the case of a public company, not less than 51% of the stock), and must control the management and daily business operations of the business.
The Vendor Information Pages Database is the only federally controlled database in which a legal verification process is used to determine service-disabled or veteran status of a small business.
Taken from http://www.vetbiz.gov.