The U.S. Citizenship and Immigration Services’ (USCIS) Nebraska Service Center (NSC) has recently begun to more aggressively review F-1 STEM Optional Practical Training (OPT) extension applications. In addition to evidencing that the student has graduated with a STEM major and is (or will be) working for an E-Verify employer, some USCIS officers at the NSC are currently requesting verification of the student’s employment history during the regular 12 month OPT period. In addition to employment confirmation letters, some officers are requesting copies of payroll statements and W-2 forms. If the student is unable to evidence that he/she had valid employment authorization during the entire OPT period, some of the USCIS officers will then explore whether the student exceeded the 90-day unemployment window during post-completion OPT. If the USCIS officer determines that the student was unemployed for more than 90 days during the post-completion OPT period, the USCIS officer may deny the STEM OPT extension application stating that the student has failed to maintain valid F-1 status.