In recent guidance, the Department of Treasury and the IRS issued proposed rules that clarify under the Internal Revenue Code (Code) that the terms “spouse” and “husband” and “wife” refer to individuals who are lawfully married to one another regardless of that person’s gender.  The guidance is in response to the recent Supreme Court decision in Obergefell v. Hodges, 135 S. Ct. 2584 (2015), which legalized same sex marriage across all 50 states.  The regulations will affect sections of the Code that involve marriage, including payroll, income, and estate tax provisions, as well as a number of dependency exemptions.  The proposed regulations instruct that the IRS’s updated interpretation of these terms in the Code does not extend to individuals who are part of a civil union or registered as domestic partners.  For more details on the impact of Obergefell on employer sponsored benefit plans, please see our prior alert here.