The FMLA permits an employer to require that an employee submit a timely, complete, and sufficient certification to support a request for FMLA leave due to a serious injury or illness of a servicemember. If requested by the employer, your response is required to obtain or retain the benefit of FMLA-protected leave. 29 U.S.C. 2613, 2614(c)(3). Failure to do so may result in a denial of an employee’s FMLA request. 29 CFR 825.310(f). The employer must give an employee at least 15 calendar days to return this form to the employer.