Claim for Refund of Tax and License Fees Erroneously Paid to the State of Maryland Through the Clerk of Court OC Form X-4 is a form used to request a refund of taxes and/or license fees that have been erroneously paid to the State of Maryland. This form is used when the individual or business believes that taxes or fees were wrongly paid to the state, for example, due to a mistake or an error in the calculation. The form is available for download from the Maryland Courts website. It must be completed in full, and all required supporting documentation must be attached. The form must be signed, dated, and returned to the Clerk of Court in the county in which the taxes or fees were paid. Types of Claim for Refund of Tax and License Fees Erroneously Paid to the State of Maryland Through the Clerk of Court OC Form X-4 include: * Refund of Business Taxes * Refund of Personal Property Taxes * Refund of Motor Vehicle Registration Fees * Refund of Motor Vehicle Excise Tax * Refund of Real Property Taxes * Refund of State Income Tax * Refund of Other Taxes/Fees.