A few years ago now, the U.S. Supreme Court has found section 3 of the Defense of Marriage Act (DOMA) unconstitutional.
Effective immediately then, U.S. government agencies began adjudicating applications for federal benefits that are based on a same-sex marriage in the same way that we adjudicate applications for opposite gender spouses.
This means that the same-sex / LGBT- spouse will be eligible for the same or derivative benefits, as would a spouse of opposite gender. Likewise, stepchildren acquired through same sex marriages can also qualify as beneficiaries or for derivative status.
If your marriage is valid in the jurisdiction (U.S. state or foreign country) where it took place, it is valid for purposes of obtaining federal government benefits. At this time, only a relationship legally considered to be a “marriage” in the jurisdiction where it took place establishes eligibility as a spouse for immigration purposes.
For most federal benefits involving children or step-children, the marriage must have taken place before the child in question turns or turned 18.
If cases were previously submitted and denied by the government, solely based on reasons relating to “DOMA”, the government will now usually reopen those petitions or applications.
The government will usually take steps to reconsider its prior adverse decision, as well as reopen associated applications to the extent they were also denied as a result of the primary denial (Example: when Form I-130 was denied, and subsequently Form I-485 is denied, all related cases will be reopened).