Apple Inc. is donating $100,000 to fight Proposition 8, which seeks to end same-sex marriage in California by amending the Constitution to define marriage as between a man and a woman.

"Apple was among the first California companies to offer equal rights and benefits to our employees' same-sex partners, and we strongly believe that a person's fundamental rights - including the right to marry - should not be affected by their sexual orientation," the company said Friday in a statement on its Web site.

Apple joins Google, which came out publicly against Prop. 8 last month. Google founders Sergey Brin and Larry Page reportedly have donated a combined $140,000 to fight the measure.

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In revealing its support, Google officials voiced similar points, saying the company sees the issue as one of equality and is opposed to the elimination of fundamental rights.

"While we respect the strongly held beliefs that people have on both sides of this argument, we see this fundamentally as an issue of equality. We hope that California voters will vote no on Proposition 8 - we should not eliminate anyone's fundamental rights, whatever their sexuality, to marry the person they love," Brin said.

It is not common practice for either company to take a stand on political measures. It remains to be seen what effect the move might have on Proposition 8 supporters, who might avoid doing business with companies that oppose the measure.