Markets were choppy as the prospect of strong corporate results ran into fresh signs that economic growth looks sluggish at best.
European shares snapped a six-day winning run, with banks sliding on worries that tough new capital and risk rules will be imposed on the sector.
But Wall Street nosed higher, led by technology stocks, after Intel Corp late on Tuesday posted forecast-beating quarterly earnings and revenue that allayed fears of a technology spending slowdown.
Global shares measured by MSCI's all-country world index rose almost 0.6 percent.
At 12:30 p.m. the Dow Jones Industrial Average was up 16.72 points, or 0.16 percent, at 10,379.74. The Standard & Poor's 500 Index was up 2.23 points, or 0.20 percent, at 1,097.57. The Nasdaq Composite Index was up 15.86 points, or 0.71 percent, at 2,257.89.
The FTSEurofirst 300 of top European shares fell less than 0.1 percent to close at 1,045.11 points.
The euro was up 0.32 percent at $1.2767.
The dollar was down against a basket of major currencies, with the U.S. Dollar Index down 0.47 percent at 83.252. Against the yen, the dollar was down 0.18 percent at 88.51.
Talk of a possible debt downgrade for Spain, heightened by a surge in borrowing by Spanish banks from the European Central Bank in June to a new record high, also eroded risk appetite and drove up the price of safe-haven assets like debt.
Earlier in Asia, stocks rose to a three-week high. Japan's Nikkei average surged 2.7 percent to its highest close in three weeks, while the MSCI ex-Japan share index was up 1.4 percent.
Spot gold prices fell $3.25 to $1,207.40 an ounce.
Meanwhile, world oil prices rose on Wednesday after data showed crude stockpiles fell by a sharper than expected amount in top consumer the United States.
New York's main contract, light sweet crude for delivery in August, climbed 75 cents to $77.90 a barrel.
Brent North Sea crude for August gained 79 cents to $77.44.
The US Department of Energy (DoE) said US crude stockpiles slumped 5.1 million barrels last week. Analyst forecasts had been for a drop of only 1.2 million barrels, according to Dow Jones Newswires.
"US crude stocks dropped by five million barrels for the second consecutive week but remained close to historical highs for this time of year," said Christophe Barret, an oil analyst for Credit Agricole.
"The crude drop is likely to be related to better refinery demand."
Oil prices extended gains after soaring Tuesday, when the dollar weakened and the International Energy Agency (IEA) forecast that demand was projected to increase slightly this year.
"In its latest monthly report, the IEA increased its outlook for 2010 oil demand growth slightly to 1.77 million barrels per day," said analysts at the JBC Energy consultancy in Vienna.
"Given the ongoing discussions of a double-dip recession and the absence of a clear sign of the sustainable recovery of the global economy, the figure seems fairly optimistic.
"Furthermore, the IEA sees demand growth in 2011 slowing down to 1.3 million barrels per day, indicating that the vast majority of the economic uptick will take place in 2010."
