By Sara Sjolin, MarketWatch

SolarCity slides premarket after earnings

LONDON (MarketWatch) -- U.S. stocks were struggling to make headway on Thursday, lower oil prices hit energy-related shares and more uncertainty over a Greece bailout vied for investor attention with the prospect of a more dovish Federal Reserve.

Investors have also been skittish ahead of a raft of quarterly results and economic reports.

Futures for the Dow Jones Industrial Average (DJH5) had been flipping between small gains and losses, but, at last check, were off 18 points to 17,977, while those for the S&P 500 index (SPH5) were off 1.8 points to 2,093.60. Futures for the Nasdaq-100 index (NDH5) stayed in positive territory -- barely -- with a four-point gain to 4,390.

Markets had closed slightly lower on Wednesday, as investors wrestled with interpreting minutes from the Federal Reserve's latest meeting, which suggested the first rate hike might come later than expected. The report showed the central bank is worried about the low rate of inflation and slow pickup in wages, emphasizing the importance of those data points.

Setback for Greece: Media reports on Thursday said Germany has rejected Greece's request for a six-month loan extension agreement, noting that their application is "not a substantial proposal for a solution." The Greek government had formally requested a six-month extension to its loan agreement, sending stocks higher in Athens. But those gains have been pared and the Stoxx Europe 600 index was flat and the euro (EURUSD)

Senior eurozone finance ministers are expected to meet later on Thursday to discuss the request, but it isn't a given that they'll grant Greece the extension. The country's antiausterity government has distinguished between a mere loan agreement and a continuation of the full bailout program, which it argues hurts the Greek society and economy. The full Eurogroup of eurozone finance ministers is scheduled to meet on Friday.

Data: Investors on Thursday might get more hints to whether wages are likely to improve, with a reading on weekly jobless claims due at 8:30 a.m. Eastern Time. Economists polled by MarketWatch expect 290,000 Americans filed for unemployment benefits last week, down from 304,000 the week before.

The Philadelphia Fed's manufacturing index for February is out at 10 a.m. Eastern. Economists expect a slight rebound to 8 from the sharp decline to 6.3 in January, compared with 24.3 in December. The leading indicators readings is scheduled for 10 a.m. Eastern as well.

Oil blues: Energy companies and oil-related funds were hit hard in premarket trade, as crude-oil prices slid and hovered around $50 a barrel. The oil slump came after reports showed a whopping jump in U.S. oil stockpiles, which underscored concerns of a supply glut. Among oil-tracking indexes, the iPath Goldman Sachs Crude Oil Total Return Index ETN (OIL) fell 3.4%, and the Velocity Shares 3X Long Crude ETN (UWTI) slumped 8.8%.

ConocoPhillips dropped 1.4% ahead of the open, while Exxon Mobil Corp. (XOM) shaved off 0.9%, and Halliburton Co. (HAL) lost 1.8%.

Earnings: It is a busy premarket lineup on the earnings front: T-Mobile US Inc.(TMUS) said it swung to a profit in the fourth quarter and reported a better-than-expected surge in revenue. Shares were unchanged ahead of the bell.

Hormel Foods Corp.(HRL) beat Wall Street's earnings expectations and raised its 2015 adjusted earnings guidance. Shares didn't move premarket.

Wal-Mart Stores Inc.(WMT) is projected to report fourth-quarter earnings of $1.54 a share, according to a consensus survey by FactSet.

Priceline Group Inc.(PCLN) shares popped 6% after profit and sales beat expectations.

DirecTV(DTV) is projected to post fourth-quarter earnings of $1.39 a share.

Movers and shakers:SolarCity Corp.(SCTY) slumped 6.3% after the solar-energy firm late Wednesday said it swung to a fourth-quarter loss of 4 cents a share, from a profit of 28 cents a share a year ago.

Counterpart SunEdison Inc.(SUNE) fell 4%. The solar-energy company late Wednesday reported a smaller-than-expected fourth-quarter loss.

BJ's Restaurants Inc.(BJRI) surged 10% after reporting a sharp rise in profit for the fourth quarter.

Other markets: In Asia, Japanese stocks rose to a 15-year intraday high, while the rest of Asia closed mixed. Chinese markets were closed for the Lunar New Year celebrations.

Gold rallied (GCJ5) after the Federal Open Market Committee minutes dashed hopes of a midyear rate hike.

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