Amazon.com hasn't always had the best reputation when it comes to charitable giving. But CEO Jeff Bezos continues to make his own stock gifts to nonprofits. Bezos gave 8,270 shares of Amazon stock to undisclosed nonprofit organizations on Aug. 18, according to a company SEC filing. Amazon stock was trading at $82.12 that day, putting the value of the Bezos gift at around $679,000.

The filing doesn't specify if the gift went to the Bezos Family Foundation or other organizations, and Amazon didn't respond for a request for comment. Bezos has made a series of nonprofit stock contributions in recent years -- more than 9,600 shares this year, 8,200 shares last year, and 21,000 shares in 2007, according to SEC filings. He had a bigger year in 2006, making gifts of 104,000 shares to nonprofits.

Amazon as a company has gotten periodically dinged for philanthropic stinginess, which is striking given that Patricia Stonesifer, the former head of The Bill & Melinda Gates Foundation, the world's biggest philanthropy, sits on the Amazon board. Recently, Amazon has taken steps to tout its charitable giving efforts on its website.

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