NEW YORK (CNNMoney.com) -- Stocks appeared poised for losses at the start of Friday's session as investors kept an eye on oil prices and worries about financial firms persisted.

At 8:10 a.m. ET, Nasdaq and S&P futures were lower, with a comparison to fair value suggesting a negative open for Wall Street.

Trading is likely to be volatile as stock futures and options and stock index futures and options all expire simultaneously Friday - a situation known as "quadruple witching."

"The market will be all over the map today," said Dave Rovelli, managing director of U.S. equity trading at Canaccord Adams. "There will be a lot of options covering."

Stocks finished Thursday's session higher after oil prices skidded. But crude prices rebounded early Friday, ahead of a special summit on oil prices that Saudi Arabia will convene this weekend.

Crude for July delivery added $2.72 to $134.65 a barrel in electronic trading. Crude prices sank nearly $5 a barrel Thursday after China said it would hike fuel prices.

With no major economic reports on tap, ongoing worries about economic weakness and the fallout from the credit crunch could pressure sentiment. Investors may also be on edge ahead of the Fed's upcoming two-day meeting, which starts next Tuesday.

Companies: Moody's Investor Service said it has lowered its credit rating on bond insurers MBIA (MBI) and Ambac Financial Group (ABK). The ratings agency cut MBIA's "Aaa" rating to "A2" and Ambac's "Aaa" rating to "Aa3" amid concerns about the companies' financial strength.

A Wachovia (WB, Fortune 500) investment unit has liquidated a fund that specialized in mortgage-backed securities worth $403 million, the Wall Street Journal reported.

The news comes amid fears about Wachovia's financial health after the company slashed jobs and announced the departure of its chief executive earlier this month.

Yahoo (YHOO, Fortune 500) is planning a major reorganization of its business, according to the Journal. The report comes amid a flurry of executive departures at the tech firm, which announced last week that merger talks with Microsoft (MSFT, Fortune 500) had failed.

Continental (CAL, Fortune 500) and UAL Corp.'s (UAUA, Fortune 500) United Airlines announced a marketing alliance Thursday that they hope will help raise revenue to offset rising fuel costs.

Live Nation (LYV) is negotiating the exit of its chairman, Michael Cohl, the Wall Street Journal reported late Thursday.

Other markets: In global trade, stocks in Asia fell for a second straight session. European markets drifted lower in morning trading.

The dollar fell against the euro as investors await decisions on interest rates from the European Central Bank and the Federal Reserve.  

NEW YORK (CNNMoney.com) -- The Nasdaq led a broader market advance Thursday after oil prices slumped nearly $5 a barrel on news out of China that could mean less demand and lower prices.

Blue-chip gains were limited by Citigroup's warning that it will take substantial second-quarter mortgage-related writedowns and a big drop in a key manufacturing index.

The Dow Jones industrial average (INDU) rose 0.3%. The broader Standard & Poor's 500 (SPX) index climbed 0.4% and the tech-heavy Nasdaq composite (COMP) gained 1.3%, thanks to strength in chips and software.

The selloff in oil prices propelled shares of airlines, truckers and railroads, bringing relief to sectors that depend directly on fuel. That lifted the Dow Jones Transportation average by 3.4%.

U.S. light crude oil for July delivery fell $4.75 to settle at $131.93 a barrel on the New York Mercantile Exchange after China said it will lift fuel subsidies on gas and diesel - a move that could curb demand in the country and lower prices globally. (Full story)

"Lower oil prices are helping today, with the China announcement a big positive," said Ron Kiddoo, chief investment strategist at Cozad Asset Management.

However, he said that the market remains at the mercy of day-to-day news and any rally could disappear if the next news item is more negative.

The financial sector briefly turned higher, with AIG (AIG, Fortune 500) gaining on a Citigroup upgrade to "buy" from "hold." But that was countered by bearish comments from Citigroup (C, Fortune 500)'s chief financial officer at an investor conference.

"The market is going to be choppy through the whole summer and maybe longer until we stop getting these kinds of announcements from financial firms," Kiddoo said.

He said that even the occasional upbeat economic report, like the recent May retail sales index or this morning's leading economic indicators (LEI) gets overshadowed by ongoing worries about the financial sector.

What would help stocks is oil continued to move downward over the next few weeks, a development that seems unlikely considering the global demand.

"If oil really starts coming down, people would eventually pull money out of energy and start putting it to work in the stock market," said Dean Barber, president at Barber Financial Group.

Stocks have been under pressure this week as oil prices have flirted with new records, adding to worries about inflation. Concerns about the ongoing credit market fallout have also been in play after Morgan Stanley and Goldman Sachs both reported big drops in quarterly profit.

There are no market-moving earnings or economic news tomorrow.

Friday brings the quadruple options expiration Friday, a quarterly event in which stock futures and options and stock index futures and options all expire simultaneously. This can sometimes add volatility to the underlying stocks.

On the move: A number of big technology stocks rose, including Intel (INTC, Fortune 500), Broadcom (BRCM), Microsoft (MSFT, Fortune 500) and Oracle (ORCL, Fortune 500).

Intel and Microsoft are Dow components. Boeing (BA, Fortune 500), Home Depot (HD, Fortune 500), Merck (MRK, Fortune 500) and DuPont (DD, Fortune 500) were among the other stocks helping to lift the Dow.

But Dow financial components JP Morgan Chase (JPM, Fortune 500) and Bank of America (BAC, Fortune 500) both dipped on Citigroup (C, Fortune 500)'s warning.

Two former Bear Stearns hedge fund managers surrendered to authorities. They are facing federal criminal charges related to the collapse of two Bear funds that made bad bets on the subprime mortgage market. (Full story).

Shares of Ford (F, Fortune 500) gained modestly on news that billionaire Kirk Kerkorian's Tracinda Corp. had boosted its stake in Ford to 6.49% from 5.5%.

Circuit City (CC, Fortune 500) reported a wider loss from a year earlier on weaker revenue due to sluggish sales amid the consumer spending slowdown. Circuit City's per-share-loss was narrower than what analysts were expecting, while the revenue drop was wider.

Market breadth was mixed. On the New York Stock Exchange, losers and winners were narrowly mixed on volume of 1.29 billion shares. On the Nasdaq, advancers beat decliners 4 to 3 as 2.29 billion shares changed hands.

Economy: The Philadelphia Fed index, a regional reading on manufacturing, weakened to minus 17.1 in June from minus 15.6 in May, a bigger drop than what economists surveyed by Briefing.com had expected. It was the index's seventh straight monthly decline. Any negative reading shows contraction in the sector.

The number of Americans filing new claims for unemployment fell modestly by 5,000 last week to 381,000, but stayed at levels that continued to reflect a struggling economy. (Full story).

Another economic report was more positive. The Conference Board's index of leading economic indicators rose 0.1% in May, as it did in April. Economists had expect LEI to remain unchanged. (Full story)

Investors were also keeping an eye on comments from Treasury Secretary Henry Paulson, who said changes need to be made to how the financial system is regulated.

Other markets: The national average price for a gallon of regular unleaded gas eased to $4.073 from $4.075 the previous day, according to AAA. (Full story).

COMEX gold for August delivery rose $10.70 to settle at $904.20 an ounce.

In currency trading, the dollar rose versus the euro and the yen.

In the bond market, Treasury prices fell, raising the yield on the benchmark 10-year note to 4.21% from 4.13% late Wednesday. Bond prices and yields move in opposite directions. 

The Dow Jones industrial average (INDU) closed down nearly 1.1% and the broader Standard & Poor's 500 index (SPX) was down 0.9%. The Nasdaq composite (COMP) was also down about 1.1% at the end of a volatile trading day.

Markets were volatile in part because investors are unwinding their positions ahead of the so-called "quadruple witching" day on Friday. "Quadruple witching" refers to the day - four times a year - when a range of options expire.

The markets began to sell off Wednesday morning following weak quarterly results from FedEx and Morgan Stanley. The selling accelerated in afternoon trading as financial stocks joined in Morgan's disappointment.

"A couple of household names have come out showing how difficult it is to make money in this market," said Art Hogan, chief market strategist at Jefferies and Company Inc.

Oil prices are also wrecking havoc on investors, with Hogan noting that crude futures are more than twice as expensive than they were this time last year.

"It is impossible to separate corporate America from energy prices and although we are down today and that is good news, we are being reminded that the high energy prices affect business," said Hogan.

Thursday brings a number of economic reports. The Labor Department reports initial claims for unemployment benefits before the opening bell. The Conference Board, a business research group, releases the Leading Indicator index, which predicts the economy's future performance. In addition, the Philadelphia Federal Reserve bank announces its regional manufacturing survey for June.

FedEx swings to loss: FedEx said it swung to a fiscal fourth-quarter loss, hurt by high fuel prices and slowing growth in its domestic-package business. Memphis-based FedEx (FDX, Fortune 500) Corp. posted a loss of $241 million. (Full story.)

FedEx is "a reflection of the overall heart of the economy because they ship goods," said Fred Dickson, chief market strategist at D.A. Davidson & Co. "We have the twin worries coming together there - energy prices and slowing overall consumer demand."

Morgan Stanley leads the financials down: Profits at Morgan Stanley (MS, Fortune 500) fell by more than half last quarter, hurt by a decline in its investment banking and sales and trading businesses, the company reported. The No. 2 investment bank reported a 57% decline in profits. (Full story.)

Other financial shares weakened. Merrill Lynch (MER, Fortune 500), Lehman Brothers (LEH, Fortune 500), and Citigroup (C, Fortune 500) were also trading in the red. Shares of Goldman Sachs (GS, Fortune 500), however, were up in early trading on Wednesday. On Tuesday, Goldman reported sales and profits down from a year ago, but the bank beat estimates.

Financials are one of the main factors leading the markets lower, according to Harry Clark, founder and CEO of Clark Capital Management Group.

Fifth Third Bancorp (FITB, Fortune 500) shares were down most of the day after announcing it will cut its dividends by two thirds. The bank also said that it is working to raise capital to protect against future loan losses. (Full story.)

Shares of the exchange-listed futures broker MFGlobal (MF) also traded down as much as 40% the day after announcing that the company will sell shares to raise $300 million to pay back debts.

Market breadth was negative. On the New York Stock Exchange, decliners beat advancers 3 to 1 on a volume of 1.28 billion shares. On the Nasdaq, decliners beat advancers 5 to 2 on a volume of 2.1 billion shares.

Airlines have to hike fares: As the price of jet fuel approaches $4 a gallon, even traditionally low-cost carriers are being forced to raise fares. Southwest Airlines (LUV, Fortune 500), known for its low fares, said at a conference will need to follow the rest of the industry to keep up with the price of oil.

Energy prices: In a nearly $5 swing from its lows, crude prices ended sharply higher Wednesday following a report that Nigerian oil workers are threatening to go on strike. U.S. crude for July delivery rose $2.67 to settle at $136.68 a barrel on the New York Mercantile Exchange. Oil traded as low as $131.82 shortly after the government released its weekly inventory report before starting the dramatic rebound in the afternoon.

Bush: U.S. "must produce more oil" Congress must face a hard reality," the president said. "Unless members are willing to accept gas prices at today's painful prices or even higher, our nation must produce more oil, and we must start now."

The remarks highlighted the growing political pressure to reduce dependence on foreign oil and deal with rising gas prices.

Gas prices fall: Retail gasoline prices eased for the second day in a row, retreating slightly from their record high, according to a daily survey released by auto club AAA. The national average price for a gallon of regular gas fell three-tenths of a cent to $4.075, according to AAA. (Full story.)

Other markets: In currency trading, the dollar lost against both the euro and the yen in afternoon trading. The dollar's decline was sparked on Tuesday with the release of a report from the Labor Department that showed increasing food and energy prices had driven up wholesale inflation in the United States by 1.4%.

COMEX gold for August delivery was up $6.60 to $893.50 an ounce.

In the bond market, Treasury prices gained, lowering the yield on the benchmark 10-year note to 4.13%. Bond prices and yields move in opposite directions.