It should be the abbreviation of the state where the dividends was received from. See discussions here: State ID
You received form 1099-OID is due to there is an original issue discount interest being reported to you. You would need to report it as part of income on your taxes. OID stands for "original issue discount". OID occurs when a bond is issued for a price less than its face value or principal amount.
**Say "Thanks" by clicking the thumb icon in a post
**Mark the post that answers your question by clicking on "Mark as Best Answer"