Updated from 7:16 a.m.

NEW YORK (TheStreet) -- Here are 10 things you should know for Thursday, May 21:

1. -- U.S. stock futures were sinking Thursday as investors felt dissatisfied with the Federal Reserve's reticence about when it would raise rates, and as big banks paid huge fines for foreign exchange rate rigging. CVS (CVS) announced a big deal to buy Omnicare (OCR).

European stocks struggled to gain momentum on Thursday after disappointing purchasing managers' data from China to Europe offset dovish minutes from the Fed's last meeting.

Asian stocks were mixed, as Tokyo's Nikkei 225 hit a new 15-year high and the Topix closed up. In Hong Kong, the Hang Seng closed down on volatile trading. Mainland Chinese indices closed up after weaker-than-expected Markit purchasing managers' data, which fueled hopes of more monetary stimulus. The Shanghai Composite Index closed strongly up.

2. -- The economic calendar in the U.S. on Thursday includes jobless claims at 8:30 a.m., the PMI manufacturing index flash at 9:45 a.m., the Philadelphia Fed business outlook survey at 10 a.m., existing home sales numbers at 10 a.m. and the Conference Board's leading indicators data at 10 a.m.

3. -- U.S. stocks on Wednesday softened from the records set earlier in the week on uncertainty over the timing of the Federal Reserve's interest rate hike.

The Dow Jones Industrial Average (DIA) fell 0.15% to 18,285.40. The S&P 500 (SPY) dropped 0.09% to 2,125.85. The Nasdaq (QQQ) moved up 0.03% to 5,071.74.

4. -- Pharmacy CVS Health (CVSwill buy Omnicare (OCR) for $12.7 billion, including $2.3 billion in debt, the companies announced Thursday morning. The move will allow CVS to sell prescriptions in long-term care and assisted-living facilities, which are Omnicare's focus. Both companies' boards have approved the deal, but Omnicare shareholders will also need to accept it.

In premarket trading, CVS stock was up 1.03%. Omnicare rose 1.2%.

5. -- The Federal Reserve released minutes from its Fed Open Market Committee recent meeting. However, the Fed kept its cards close it its vest about when an increase in interest rates would finally come. The economy needs to show stable growth before the Fed will boost rates, the report said.

The Fed has not increased interest rates since 2006, and interest rates have been at 0% since 2008. Market players are keenly interested in when the Fed will raise rates, although it will likely do so in small increments.

6. -- Initial jobless claims data came in at 274,000 for last week. Unemployment claims are hitting a 15-year low. Analysts at Econoday anticipated that about 270,000 new jobless claims were reported for last week, slightly below the actual figure. Two weeks ago, 264,000 unemployment claims were reported.

A low number of unemployment claims indicates an improving economy and may nudge the Fed into raising rates sooner rather than later.

7. -- Oil company BP (BP) has settled its dispute over the 2010 Deepwater Horizon oil spill with Halliburton (HAL) and Transocean (RIG). In September, a judge ruled that BP was primarily at fault for the spill, not Transocean (which owned the rig in question) or Halliburton. Transocean and Halliburton have paid about $1 billion each in fines for their role in the disaster. BP will pick up most of the tab, though, with a potential $13.7 billion fine for violating the Clean Water Act.

In premarket trading, BP's ADRs were rising by 1.24%.

8. -- Barclays (BCS), Citigroup (C), JPMorgan Chase (JPM) and the Royal Bank of Scotland (RBS) have joined UBS (UBS) in paying huge fines for their role in rigging foreign exchange and interest rates. In total, the banks will pay fines of $5.9 billion. And all those banks but UBS will plead guilty to violating antitrust laws, as well. (UBS has pleaded guilty to wire fraud.)

Despite the rebuke, large-cap bank stocks have been rising faster than the wider markets this quarter.

In premarket trading, Citigroup was falling by 0.26%, JPMorgan Chase was rising by 0.02% and UBS's New York-traded stock was down 0.23%. Barclays ADRs were rising by 0.77%, and RBS was level.

9. -- Protestors demonstrated in front of McDonald's (MCD) Oak Brook, Ill., headquarters Wednesday to demand a raise to $15 an hour. McDonald's claimed that it couldn't tell franchisees what to pay their employees. McDonald's directly owns only about 10% of its stores; the rest are franchised.

McDonald's annual shareholder meeting takes place Thursday. A smaller protest is planned.

In premarket trading, McDonald's stock was down 0.29%.

10. -- On the earnings calendar today, there are reports from Aeropostale (ARO), Best Buy (BBY), Dollar Tree (DLTR), Gap (GPS), Hewlett-Packard (HPQ) and Intuit (INTU).

Best Buy's quarterly earnings and revenue beat expectatations, and the stock is rising by 6.22% in premarket trading.

More from Stocks

Time Warner's Jeff Bewkes: Department of Justice Theories Are 'Ridiculous'

Time Warner's Jeff Bewkes: Department of Justice Theories Are 'Ridiculous'

Amazon, Procter & Gamble, Southwest and Netflix - 5 Things You Must Know

Amazon, Procter & Gamble, Southwest and Netflix - 5 Things You Must Know

Just How Bad Is Facebook's Diversity Problem?

Just How Bad Is Facebook's Diversity Problem?

2 More Reasons to Sell All Your Stocks and Run Away

2 More Reasons to Sell All Your Stocks and Run Away

Why Aren't Markets Thinking About the Risk of a Syrian Counterattack?

Why Aren't Markets Thinking About the Risk of a Syrian Counterattack?