Sample Letter of Authorization. Please be advised that.A Letter of Authorization authorizes payment for medical services received over 12 months before the current month. This Authorized Representative form is enclosed for this purpose. If you want to authorize someone to represent you at the hearing, please complete this form. The requesting physician must complete all identifying information regarding the employee, the claims administrator, and the physician. What are some samples of authorization letters? Authorization letters are letters that empower someone else to take actions on your behalf. Include the full legal name of the authorized party and their relationship to the account holder. Account Holder Signature(s):.