Since 1986, employers in the United States have been required to confirm work authorization and verify the identity of their employees whether they are US citizens or foreign nationals. To do so, employers and employees must complete the Form I-9, Employment Eligibility Verification—which has recently been revised and updated—within the first three business days of the commencement of employment. E-Verify, launched in 1997, was created to add another level of verification. E-Verify is a voluntary (for most) and free, Internet-based system that compares information from an employee's Form I-9 to data from the US Department of Homeland Security (DHS) and Social Security Administration (SSA) records to confirm employment eligibility. Over 600,000 companies are currently enrolled in E-Verify with more than 1,400 new participating companies every week.