Married 5 years and the 401K plan was started prior to marriage. Will spouse get half in Oregon under legal separation proceedings?

She may get half of any contributions made during the marriage. She would need to file a QDRO as part of the divorce. The 401(k) would probably not be part of a separation.

No she won't get anything at this point until the divorce is final except a possible decree from the courts stating that no modification is to take place until the final order.