New York (CNN) Wall Street's leading banks have signed a "friend of the court" brief pressing the Supreme Court to back same-sex marriage.

Major financial firms including AIG, Bank of America, BlackRock, Credit Suisse, Deutsche Bank, Goldman Sachs JPMorgan, UBS and Wells Fargo signed the brief that will be filed on Thursday.

Spokespeople at each of the companies confirmed to CNN that they are named in the brief. Other signatories include a range of small and large companies in a variety of sectors including technology, healthcare and retail.

"The brief argues that the existing confused legal landscape places significant burdens on employers and their employees—making it increasingly hard to conduct business," said Elliott Frieder, a spokesman for Morgan, Lewis & Bockius, the law firm that will file the brief on behalf of the firms.

The case, Obergefell v. Hodges, centers around the question of whether states are required to recognize the marriage laws of other states. It originated in Ohio, where same-sex couple James Obergefell and John Arthur argued that the state discriminates against couples that were married out-of-state. They were married in Maryland.

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