* Euro zone to seek Greek aid deal without write-off
* Qatar cashes in Barclays warrants, shares dip
* Knight Capital in talks for unit sale; shares jump in premarket trade
* Futures lower: S&P 4.9 pts, Dow 52 pts, Nasdaq 4.25 pts
By Angela Moon
NEW YORK, Nov 26 (Reuters) - Wall Street was set for a lower open on Monday as investor returned to the market after a holiday-shortened trading week, focused on the meeting of euro zone finance ministers on Greece and negotiations over the U.S. "fiscal cliff."
Euro zone finance ministers and the International Monetary Fund will seek to unfreeze the second bailout package for Greece on Monday, but they first need to agree if some of the official loans to Athens might eventually be forgiven to cut Greek debt.
U.S. lawmakers have made little progress in the past 10 days toward a compromise to avoid the harsh tax increases and government spending cuts scheduled to start taking effect on Jan. 1, a senior Democratic senator said on Sunday.
"On the most pressing issue for the markets into year end, that of the tax and spending issues in the U.S., the Sunday morning talk shows didn't reveal that we're on the cusp of a deal as more horse trading will go on in the weeks to come," said Peter Boocvkar, managing director at Miller Tabak & Co in New York.
S&P 500 futures lost 4.9 points and were below fair value, a formula that evaluates pricing by taking into account interest rates, dividends and time to expiration on the contract. Dow Jones industrial average futures fell 52 points, and Nasdaq 100 futures dropped 4.25 points.
Investors were also ready to book profits after the Dow and S&P 500 both closed above key technical levels for the first time since Nov. 6 on Friday. The Dow ended above 13,000, while the S&P broke above 1,400. For the week, the Dow rose 3.3 percent for the week, while the Nasdaq jumped 4 percent. The Nasdaq had ended lower for the previous six weeks in a row.
Knight Capital Group Inc is in talks about possibly selling its market-making operation, its largest and most profitable business, but it is not known if a deal will happen, sources familiar with the matter said on Saturday. The stock jumped 13.7 percent to $2.83 in premarket trade.
Qatar has cashed in its remaining warrants in Britain's Barclays Plc, a move that should yield a $280 million profit and still leaves the sovereign wealth fund as the bank's top shareholder following a controversial fundraising in 2008. U.S.-listed shares of Barclays fell 5.1 percent to $15.45 in premarket trade.
Apple Inc has asked a federal court to add six more products to its patent infringement lawsuit against Samsung Electronics Co, including the Samsung Galaxy Note II, in the latest in move in an ongoing legal war between the two companies.
U.S. shoppers went to stores earlier this Thanksgiving weekend and bought online more than in years past, giving retailers a strong start to the holiday shopping season, data showed on Sunday. Total spending for the long weekend rose to $59.1 billion, up 12.8 percent from last year, according to the National Retail Federation.
Black Friday's online sales topped $1 billion for the first time ever as more consumers used the Internet do their early holiday shopping, comScore Inc said on Sunday.
Over the weekend, separatist parties from Spain's Catalonia region won almost two-thirds of seats in the local parliament, backed by voters frustrated over the country's economic crisis and a tax system seen as unfair to the wealthy region.
European banks have asked the European Commission to postpone the introduction of tougher global bank capital rules by a year to 2014 after U.S. regulators delayed application of the new requirements.
U.S.-based stock funds suffered the most outflows since late July as U.S. lawmakers inched ahead in talks to avert the "fiscal cliff" of tax hikes and spending cuts set to occur in January, data from Thomson Reuters' Lipper service showed on Friday.
U.S. stocks rose for a fifth day during a holiday-shortened, thinly traded session on Friday as investors picked up recently beaten-down shares of large technology companies.