The Dow Jones Industrial Average (DJINDICES: ^DJI) plunged more than 160 points as of 11:30 a.m. EST. Dow component IBM (NYSE: IBM) defied its index, posting a minor gain, while shares of Logitech (NASDAQ: LOGI) rallied more than 20%. Nokia (NYSE: NOK) was a notable tech loser, as shares fell nearly 10% in morning trading.

U.S. stocks drop following disappointing Chinese data
The sell-off in the Dow Jones may have been prompted by Chinese economic data. Last night, HSBC's Chinese purchasing managers' index came in worse than economists expected -- a reading of 49.6 versus the 50.6 estimate -- and indicated that China's manufacturing sector is contracting. In addition, the Bank of Japan hinted that it may be less stimulative going forward.

Both factors could weigh on U.S. equities, as China remains the world's second largest economy and the Bank of Japan has been particularly aggressive in its economic stimulus measures in recent months.

IBM sells server business to Lenovo
IBM edged up a modest 0.3%. The rally was likely prompted by IBM's announcement that it would sell its low-power server business to Chinese PC giant Lenovo. IBM will get $2 billion in cash and $300 million in shares in the deal.

IBM's performance has been disappointing in recent quarters, and the company's latest earnings report came in below analyst expectations on Wednesday. Shedding this part of its operations may prove beneficial to shareholders.

Nokia posts disappointing earnings
Shares of Nokia plunged on Thursday after the company reported earnings. For the the fourth quarter, earnings fell 27% from the prior year and sales dropped 21%. Nokia sold 30 million Lumia handsets in 2013, but fewer than expected in the fourth quarter.

But Nokia investors won't have to mind the company's handset business for much longer -- Microsoft is set to take over that part of the company's operations.

Logitech reports strong quarter
In contrast, another European-based company, Logitech, was surging on Thursday -- shares gained more than 20% in early trade. Like Nokia, the move was related to earnings, but in this case results came in far better than expected.

Logitech beat analyst expectations for earnings and revenue, and also raised its guidance. Investors may have thought that Logitech, as a supplier of PC accessories, would have been hurt by the weakness in the PC space. However, Logitech seems to have successfully transitioned to mobile, as sales of its tablet accessories grew 95%.