Carl Icahn isn't the only billionaire investor with an appetite for Apple's stock.
Regulatory documents filed Wednesday show wealthy financier George Soros more than doubled his stake in the iPhone and iPad maker in recent months.
Soros' fund held 66,800 shares of Apple Inc. stock at the end of June, up from 26,800 shares in March.
The disclosure came a day after Icahn took to his Twitter account to announce he has built a large stake in Apple, too.
Icahn hasn't yet specified how much Apple stock that he owns, but has already urged Apple CEO Tim Cook to increase the amount of money that the company is spending to buy back its stock.
Soros hasn't indicated that he intends to pressure Apple to do things differently.
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