US SB2197

Allows legally married same-sex couples to amend tax returns filed before September 16, 2013, to change their filing status from separate to joint returns

Extends the statute of limitations for filing amended returns and claiming refunds for affected couples until the tax filing deadline for the year this Act is enacted

Applies to individuals first recognized as married under IRS Revenue Ruling 2013-17, which followed the Supreme Court's Windsor decision striking down the Defense of Marriage Act

Removes the standard cap on refund amounts (normally limited to taxes paid within 3 years) for these specific amended returns

Restricts the extended filing period solely to amendments related to changing marital status; other types of amendments remain subject to normal deadlines