On Oct. 23, 2008, the Department of Homeland Security (“DHS”) issued a final version of its “no-match letter” regulation and has filed a motion to vacate the preliminary injunction issued by the U.S. District Court, Northern District of California, which is barring its implementation. The no-match regulations describe the steps an employer should take when it receives a letter from a government agency advising that an employee’s social security or I-9 information cannot be verified. An employer who receives such a notice and takes no action can be found to have constructive notice that the employees mentioned in the letters were unauthorized workers and face both civil and criminal penalties for continuing to employ such persons. However, by taking the voluntary procedural and time-limited steps outlined in the no-match regulations, the employer can qualify for “safe harbor” provisions and shield itself from a finding that it had constructive knowledge of the employees’ unauthorized status. Importantly, these safe harbor regulations do not protect an employer who has actual knowledge that its workforce is unauthorized. Know what to do when your company receives a no-match letter, and contact your immigration counsel to put together a plan of action.