This is going to be a busy trading day.
Here are the four things you need to know before the opening bell rings in New York:
1. Greek drama rattles Europe: The main stock market index in Greece is getting pummeled and the rest of Europe's stock markets are down after the European Central Bank said late Wednesday that it would no longer accept Greek government bonds as collateral.
"In short, the ECB has commenced cutting off Greece's cash lifelines," explained Mike O'Rourke, chief market strategist at JonesTrading.
Greece's new government has been suggesting different ways for it to repay its massive bailout debts to its European partners, but the ECB move shows it faces an uphill battle.
Market watchers continue to warn that a Greece exit from the eurozone is still in the cards.
2. U.S. premarket moves: U.S. stock futures are relatively steady ahead of the open. All the major U.S. indexes took a small tumble in late dealing Wednesday in reaction to the ECB announcement.
The Dow Jones industrial average closed off its highs for the day, gaining only 6 points. The S&P 500 fell 0.4% and the Nasdaq lost 0.2%.
3. Earnings and economics: Dunkin Brands (DNKN) and Michael Kors (KORS) are among the key companies reporting results before the opening bell.
Yum! Brands (YUM) -- the company that owns KFC, Pizza Hut and Taco Bell -- just reported results that showed the firm is still struggling in China after being slammed by a food scandal last year.
Twitter (TWTR), LinkedIn (LNKD), GoPro (GPRO), and News Corp (NWS) will report after the close.
The U.S. government will post weekly jobless claims at 8:30 a.m. ET. December's trade balance will also come out at the same time.
4. Stock market movers -- Keurig, Fox, BT, Sony: Shares in Keurig Green Mountain (GMCR) fell in extended trading after the company said it had a weaker than expected holiday season.
Watch trading in 21st Century Fox (FOX), which could be on the move after the company reported earnings late Wednesday. The results impressed Wall Street, but CEO Rupert Murdoch delivered an apology to investors about poor ratings at Fox.
Shares in BT (BT) are jumping in London by about 5% after the company agreed to pay £12.5 billion ($19 billion) to buy mobile operator EE.
Sony's (SNE) stock soared 12% in Tokyo after the company reassured markets that last year's cyberattack would not have a significant impact on earnings.
