Bloomberg reports that Apple is among 60 companies that have signed on to a filing that will be presented to the Supreme Court backing gay marriage in the United States. The court is currently weighing the constitutionality of California's Proposition 8, in which voters barred gay marriage in 2008. Apple had publicly opposed Proposition 8 at the time.“No matter how welcoming the corporate culture, it cannot overcome the societal stigma institutionalized by Proposition 8 and similar laws,” the companies will argue, according to a copy of the brief provided by Or