Apple's charitable contributions continue to grow, with another half-million dollars given to SF Gives, a charity that fights poverty in San Francisco, Calif.

The donation from Apple, which was revealed by sources to Fortune, brings SF Gives $500,000 closer to reaching its goal of $10 million to fund local charitable programs. SF Gives hopes to have a total of 20 businesses contribute to reach that mark.

Other companies that have reportedly pitched in to SF Gives are Google, LinkedIn and Zynga. There have been 15 corporate contributors thus far, Monday's report said.

Still, 10 or so companies are said to have declined chipping in, citing their own, separate charitable contributions. SF Gives hopes to reach the $10 million mark by a self-imposed deadline of Wednesday.

Donations to SF Gives through the Tipping Point Community are not limited to corporations. Individuals can also contribute at the program's official website.

Under Chief Executive Tim Cook, Apple has been much more open about its philanthropic endeavors than it was under the leadership of secretive company co-founder Steve Jobs. But perhaps Apple's greatest charitable contribution has come from a program started under Jobs: Product (RED) devices, which to date have raised more than $70 million for the Global Fund to Fight AIDS.