European shares were up 0.3 percent on Wednesday morning while the euro was flat, with many investors out of the markets after Germany reiterated its staunch opposition to common bonds to share the euro zone's debt burden ahead of a European crisis summit.

Best Buy Co Inc (BBY.N) will be in focus after sources said founder Richard Schulze is working with banks including Credit Suisse (CSGN.VX) to explore a potential private takeover of the world's largest consumer electronics retailer. Shares of Best Buy trading in Frankfurt (BBY.F) were up 3.1 percent.

On the macro front, investors awaited May durable goods orders, due at 1230 GMT. Economists in a Reuters survey expect a 0.4 percent rise in May orders compared with an unchanged reading in April. Also on deck, pending home sales for May, due at 1400 GMT.

Drugmaker Bristol-Myers Squibb Co (BMY.N) on Tuesday said its board authorized the repurchase of $3 billion of the company's common stock in addition to the $3 billion share buyback program it announced in 2010.

A judge on Tuesday backed Apple Inc's (AAPL.O) request to stop Samsung Electronics (005930.KS) selling its Galaxy Tab 10.1 tablet in the United States, giving the iPhone maker a significant win in the global smartphone and tablet patent wars.

Google Inc (GOOG.O) plans to unveil a $199 tablet co-branded with Tawian's Asustek Computer Inc (2357.TW) at its developer conference this week, taking direct aim at Apple Inc's (AAPL.O) iPad, Bloomberg reported, citing two people familiar with the matter.

H&R Block Inc (HRB.N) posted a lower fourth-quarter profit on charges related to job cuts earlier this year, but the top U.S. tax preparer said it gained market share in the highly competitive tax filing business.

Qatar Holding's shock rebuff of Glencore's (GLEN.L) offer in its $30 billion takeover bid for miner Xstrata (XTA.L) indicates a new, muscular stance by the sovereign fund which had long been content to be the quiet investor in its big-name portfolio. Late Tuesday, Qatar, Xstrata's second largest shareholder and a potential kingmaker for the deal, said Glencore should pay 3.25 of its shares per Xstrata share, rather than the 2.8 on offer.

Wall Street's top financial firms delivered highly-anticipated assessments of social networking phenomenon Facebook Inc (FB.O) on Wednesday, giving a cautious nod of approval about the company a month after its rocky initial public offering.

Sealy Corp's (ZZ.N) second-quarter profit beat analysts' expectations as the mattress maker gained from a shift to higher priced products.

Major U.S. stock indexes bounced back on Tuesday, but trading was light with the outlook clouded by doubts before yet another summit to tackle the European debt crisis.

The Dow Jones industrial average .DJI rose 32.01 points, or 0.26 percent, to 12,534.67. The S&P 500 Index .SPX gained 6.27 points, or 0.48 percent, to 1,319.99. The Nasdaq Composite Index .IXIC gained 17.90 points, or 0.63 percent, to 2,854.06.

(Reporting by Blaise Robinson; editing by Ron Askew)

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