Stock index futures were little changed on Friday, following a late rally in a choppy session on Wall Street as investors positioned for the expiration of futures and options contracts.

Four types of June equity futures and options contracts expire Friday, a convergence known as quadruple witching. Traders expected a quiet session as volatility has receded lately.

I believe most of the action takes place early in the(expirations) week. You might have a volatile close, but most of the real volatility precedes the expiration, said Peter Cardillo, chief market economist at Avalon Partners in New York.

For most of the day, it is probably going to be a non-event market, barring any unforeseen news.

S&P 500 futures up 0.6 of a point and were flat in terms of 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 dipped 6 points and Nasdaq 100 futures were up 1.5 point.

At Thursday's close, open interest in the SPDR S&P 500 fund , commonly called the Spiders, showed calls and put options clustered around the $110 strike. The SPDR is currently down 0.5 percent at $111.58, which suggests the S&P 500 index will likely close near the 1,110 level.

The euro, a yardstick used lately by traders to gauge risk aversion, held at three-week highs against the U.S. dollar and was on track for its second straight positive week and its strongest week in percentage gains in at least nine months.

BP Plc shares rose 2.7 percent to $32.57 in premarket trading in New York after its chief executive survived a bruising appearance before a U.S. congressional committee and on hopes its $20 billion oil spill compensation and clean-up fund will cap public anger.

Motorola Inc will buy back most of its debt and pump the bulk of its remaining cash into a proposed spinoff of its money-losing mobile devices unit, the Wall Street Journal reported, citing sources.

Private equity group Kohlberg Kravis Roberts & Co will buy Intelligence Ltd, a unit of cable broadcaster Usen Corp <4842.OJ>, for 32.5 billion yen ($357 million) in its first significant deal in Japan.

A Democratic bill to extend jobless benefits and raise taxes on investment fund managers failed a key vote in the U.S. Senate on Thursday, dealing a blow to U.S. President Barack Obama's push to boost the economy.

U.S. stocks edged higher on Thursday in a choppy, thinly traded session as investors built on momentum after the S&P 500 index broke through its 200-day moving average earlier this week.

The S&P 500 has held above the average since Tuesday in a bullish signal, but could find resistance near the 1,121 level, a key technical level that marks the 50 percent retracement of its decline from the October 2007 historic highs to the lows of March 2009.

(Additional reporting by Angela Moon; editing by Jeffrey Benkoe)

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