USCIS has published a new version of Form I-407, the Record of Abandonment of Lawful Permanent Status. Users can begin using the form as of March 23, 2015; it is available on the USCIS website. The current edition is dated 2/26/2015. Previous form editions will not be accepted.
Form I-407 allows nonimmigrants to formally record with USCIS their decision to voluntarily abandon their status as a lawful permanent resident (LPR) of the United States. There is no filing fee.