According to an April 14, 2011 U.S. Citizenship and Immigration Services (USCIS) release, a final rule has been adopted, without change, for the interim rule (which has been in effect since April 3, 2009) to improve the integrity of the Employment Eligibility Verification (Form I-9) process. Employers and others are required by the process to verify the identity and employment authorization of each person they hire for employment in the United States (see section 274A(a)(1)(B) of the Immigration and Nationality Act, 8 U.S.C. 1324a(a)(1)(B)). The main changes made to the Form I-9 process by the interim rule and adopted by the final rule include prohibiting employers from accepting expired documents for completion of Form I-9 and adding and modifying several documents on the Lists of Acceptable Documents. The final rule became effective on May 16, 2011. According to the USCIS release, the final rule confirms that no new Form I-9 is being issued, and that employers may continue to use the current version of the Form I-9 (Rev. 08/07/2009), or the previous version (Rev. 02/02/2009).