Apple Inc.'s (AAPL - Get Report) statement that it will sell fewer iPhones in China than initially expected sent chills down the spines of stock investors Thursday. 

Not only did Apple fall more than 9% to almost $140 a share Thursday, but the entire U.S. market was down. Apple's warning is yet another strong indicator that the Chinese economy is slowing, causing investors to flock from equities. 

One casualty of Apple's many may not be immediately thinking about: Warren Buffett. 

Berkshire Hathaway Inc. Class A (BRK.A - Get Report) is the second largest Apple shareholder in the world, owning about 5.32% of the company. Berkshire, which has only bought more Apple stock of late, was down more than 5% Thursday. Vanguard is the largest Apple shareholder, owning about 6.99%, according to FactSet. Vanguard has sold tons of Apple stock in the past month. 

Elsewhere, companies with heavy Chinese exposure were getting crushed. Skyworks Solutions Inc., (SWKS - Get Report) , an Apple chip supplier, was losing more than 11% Thursday. Not only does Skyworks derive almost half of its revenue from Apple, but it gets more than 80% of its revenue from Chinese buyers, which Apple is one of. 

Wynn Resorts, Limited (WYNN - Get Report) stayed pretty flat on the day. It gets more than 70% of its revenue from China. Wynn is down 14% in the past month, during which time investors have reconciled that the Chinese economy is due to slow down soon. 

Qorvo Inc. (QRVO - Get Report) , a chip maker, gets about 50% of its revenue from China. It was down almost 10%. 

As for Apple itself, hey maybe it's time to hop in and buy the thing, RealMoney's Kevin Curran wrote. The stock has been plummeting the last few months, and Thursday, Wall Street issued several downgrades to the stock. Now it's trading at a somewhat attractive 11.65 trailing one year price-to-earnings ratio. 

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