“This is good for our company and clients, but more importantly, it’s the right thing to do,” JPMorgan Chief Executive Officer Jamie Dimon said in a statement from the New York-based bank, the largest in the U.S. by assets. “The rights of all people are important and must be protected.”

The court overturned by a 5-4 majority the U.S. Defense of Marriage Act, rejecting many of the justifications for treating same-sex and heterosexual couples differently. The court also reinstated a judge’s order allowing gay marriages in California, the nation’s largest state by population.

Some of the biggest financial firms have criticized prohibitions of same-sex marriage, saying the measures could make it harder to recruit staff. Insurer Chubb Corp., which highlights the benefits it offers to domestic partners, said in 2011 that DOMA “imposes burdens” on businesses.

“Marriage equality lowers burdens and challenges imposed on employers, and will lead to building successful businesses and a strong American economy,” New York-based Goldman Sachs said in an e-mailed statement. “We strongly support the Supreme Court’s affirmation today of marriage equality.”

The ruling could simplify administrative duties for employers in states like New York where gay marriage is legal, said J.D. Piro, national practice leader for the health-and- benefits legal practice at Aon Plc’s Aon Hewitt consulting business.

Joint Returns

“Now, according to the decision, you look at the state law’s definition of what is a marriage, and who is a spouse, and interpret the federal law that way,” Piro said in a phone interview. “So in New York, for example, whereas previously you had to file separate federal income tax returns but a joint New York state income tax return, now you’d be able to file a joint federal return.”

Apple Inc., the world’s most valuable technology company, and Citigroup Inc., the third-largest U.S. bank by assets, also welcomed the court’s decision.

“Apple strongly supports marriage equality,” Kristin Huguet, a spokeswoman for the Cupertino, California-based company, said in an e-mail. “We consider it a civil rights issue.”