Per the FAQ section of the Oregon Department of Revenue website, if you want your Oregon refund apportioned between spouses, you need to request it in writing. When your return is processed, the department will notify you with details on how the refund will be applied. Once you receive that notice, you must send a request to the department of revenue within 30 days. You must include a copy of your federal return, including federal Form 8379, Injured Spouse Allocation.
Address your refund request to:
Oregon Department of Revenue
955 Center Street NE
Salem OR 97301-2555
Note that any link in the information above is updated each year automatically and will take you to the most recent version of the document at the time it is accessed.