Stocks closed higher on Thursday with the major averages holding onto their gains after the Nasdaq reopened from a more than three hour trading halt.
A technical problem led to a halt of all Nasdaq trading shortly after midday. Shares of Nasdaq OMX were sharply lower following the halt.
Markets rose on encouraging manufacturing data out of the U.S., China and euro zone that pointed to global growth. But uncertainty persists as to when the Federal Reserve may begin to reduce its monthly bond purchases.
The Dow Jones Industrial Average rose, snapping a six session losing streak, led by gains Microsoft and Alcoa. Hewlett-Packard was a drag, down sharply after its earnings report on Wednesday. Despite today's fall, HPQ is still the best Dow stock this year, with a gain of 55 percent.
Among S&P sectors, energy and industrials paced the advance, while tech lagged.
Billionaire investor Carl Icahn tweeted on Thursday that he plans to meet with Apple's Tim Cook in September to discuss details of a possible stock buyback. What will be discussed is the magnitude of the shares repurchased, Icahn said.
(Read more: Icahn to meet with Apple CEO to discuss buyback)
Global data encouraging, Fed fears linger
Economic data is what drove markets on Thursday. The latest jobless claims report showed a rise in initial claims to 336,000, a bit higher than the 330,000 economists were looking for. July leading indicators were better than expected and Markit's "flash" U.S. manufacturing purchasing managers index posted its best showing since March.
"I do think the economy is in better shape than most people think, and that's why I think this setback over the last few days is a buying opportunity," Jim McCaughan of Principal Global Investors said.
In global economic data, HSBC's preliminary reading of Chinese PMI for August crossed the key 50-level for the first time in four months thanks to a rebound in new orders, pointing to potential stabilization.
"China's manufacturing growth has started to stabilize on the back of modest improvements in new business and output. This is mainly driven by the initial filtering through of recent fine-tuning measures and companies' restocking activities," said Qu Hongbin, the co-head of Asian economic research at HSBC.
European markets closed higher after Germany's PMI for August climbed in July. Broader euro zone PMI data also beat expectations.
"They're certainly good numbers, and we've been seeing this for the last four or five months in Europe," Richard Jerram, chief economist at the Bank of Singapore, told CNBC. "It does seem that as the headwinds from fiscal tightening fade, then the economies are starting to lift."
(Read more: Euro zone flash PMI at highest level since June 2011)
There remains ongoing uncertainty as to when the Fed will start tapering its massive stimulus program, however. Minutes from the central bank's last policy meeting, released on Wednesday, showed the Fed is preparing to start tapering, but provided little indication as to when it might do so.
UBS economist Maury Harris told CNBC, "The Fed is just apparently unable to send any kind of consistent message about what they're up to." Harris expects tapering to start in the fourth quarter, but it could be a "tiny taper" and "hardly enough to make any kind of difference."
The annual Fed symposium will start in Jackson Hole, Wyoming, on Thursday evening. Fed Chairman Ben Bernanke will break with tradition and not attend this year,and there will be plenty of speculation at the meeting as to who will replace him in January.
Retailers in focus
Retailers struggled following a weak earnings report from teen retailer Abercrombie and Fitch, which badly missed Wall Street expectations on both earnings and revenue. Shares tumbled nearly 20 percent.
Sears Holdings also got slammed after reporting a wider-than-expected loss of $1.46 a share, sending its stock down 8 percent.
GameStop shares surged after its earnings report.
Elsewhere, J.C. Penney announced a short-term stockholder rights plan.