You must have and post a Minor Work Permit for every workplace where you employ one or more people under 18 years of age. What does an employer have to do to hire minors?Post a current Minor Work Permit endorsement. All minors who wish to work in Washington are required to obtain a work permit. This guide covers the cost, timeline, and process for filing Form I-765, also known as the Application for Employment Authorization. Use Form I9 to verify the identity and employment authorization of individuals hired for employment in the United States. First, you should have a job offer. Then complete and sign the Request for Work Permit Form, and bring it in person to school to have it processed. Employer's work permit. The University maintains a general work permit exemption as a Washington state institution and public employer.