Updated from 6:08 a.m. ET

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Here are five things you must know for Tuesday, June 27:

1. -- U.S. stock futures pointed lower on Tuesday, June 27, and European shares turned mixed ahead of an appearance by Federal Reserve Chair Janet Yellen that investors hope will shed more light on expectations for the next interest rate hike from the U.S central bank.

Yellen is scheduled to discuss global economic issues with Lord (Nicholas) Stern, president of the British Academy in London, at 1 p.m. ET.

Other top central bank officials -- such as European Central Bank President Mario Draghi, Bank of England Gov. Mark Carney and Fed Presidents Patrick Harker and Neel Kashkari -- will be making the rounds on Tuesday.

The economic calendar in the U.S. on Tuesday also includes the S&P Corelogic Case-Shiller Home Price Index for April at 9 a.m., and Consumer Confidence for June at 10 a.m.

2. -- Alphabet Inc.'s (GOOGL) - Get Report Google division was fined a record €2.42 billion ($2.7 billion) by the European Commission for abusing its dominance as a search engine by giving itself an advantage in comparison shopping services.

"What Google has done is illegal under EU antitrust rules," said Competition Commissioner Margrethe Vestager. "It denied other companies the chance to compete on the merits and to innovate. And most importantly, it denied European consumers a genuine choice of services and the full benefits of innovation."

Google now has 90 days to end its conduct or face payments of up to 5% of the average daily global revenue of its parent company, Alphabet Inc., the commission said.

The fine is the largest in EU history, topping the €1.06 billion penalty levied on Intel Corp. in 2009.

Alphabet shares fell 1.2% in premarket trading.

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3. -- Sprint Corp. (S) - Get Report is in into exclusive talks with Charter Communications Inc. (CHTR) - Get Report and Comcast Corp. (CMCSA) - Get Report about a partnership that could bolster the cable companies' plans for wireless services, The Wall Street Journal reported, citing people familiar with the matter.

Sprint and the cable companies have entered into a two-month, exclusive agreement for discussions through late July, putting merger talks with T-Mobile US Inc. (TMUS) - Get Report on hold, the people told the Journal.

One arrangement under consideration is for Charter and Comcast to invest in improving Sprint's network in exchange for favorable terms to offer wireless service using Sprint's network, the people said. The cable companies could take a stake in Sprint under such a deal, some of the people told the Journal.

The talks also include the possibility for the cable companies to jointly acquire Sprint, some of the people said, but that scenario is seen as much less likely.

Sprint rose 6.2% in premarket trading on Tuesday.

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4. -- Swedish automaker Volvo Cars and supplier Autoliv Inc. (ALV) - Get Report signed a deal with Nvidia Corp. (NVDA) - Get Report to develop advanced systems and software for self-driving cars.

The three companies will work together along with Zenuity -- a joint venture equally owned by Volvo and Autoliv -- to develop next-generation self-driving car technologies, the companies said in a statement.

Production vehicles built on Nvidia's computing platform are planned for sale by 2021.

"Artificial intelligence is the essential tool for solving the incredibly demanding challenge of autonomous driving," said Nvidia CEO Jensen Huang. "We are building on our earlier collaboration with Volvo to create production vehicles that will make driving safer, lead to greener cities and reduce congestion on our roads."

Nvidia gained 0.5% in premarket trading.

5. -- General Motors Co. (GM) - Get Reportlowered the forecast for industry-wide new vehicle sales in the U.S. to the "low 17 million" unit range.

"The market is definitely slowing -- it's something we are going to monitor month to month," said Chief Financial Officer Chuck Stevens in a conference call with analysts. "Pricing is more challenging."

The automaker previously said it expected new vehicle sales in 2017 in the "mid-17 million" unit range.

The auto industry reported a record 17.55 million new vehicles were sold in 2016.

GM also said it expects the charge for the sale of its Opel unit to French carmaker Peugeot to be $5.5 billion; it previously estimated the charge would be $4.5 billion.

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