U.S. stock market index futures were slightly lower Monday, after major averages finished higher for the fourth-consecutive week, amid ongoing concerns the Federal Reserve may begin to taper off its quantitative easing program sooner than expected.
(Read More: Why This Week Could See Start of of Risk-Off)
Last week, both the Dow and S&P 500 hit fresh highs and all three major averages logged their fourth-straight weekly gains. The S&P 500 closed at 1,667 points, and is up nearly 150 percent since the financial crisis when it reached a low of 666.79 in March 2009.
This week's highlight will be Fed Chairman Ben Bernanke's testimony before the Senate on Wednesday, which may illuminate the Fed's plans regarding reducing or ending bond purchases.
With that in mind, a speech by Chicago Fed president Charles Evans will be listened to with interest on Monday, especially as Evans is a voting member of the FOMC (Federal Open Market Committee). Last week's comments by the Fed's John Williams and Charles Plosser suggested they were both were open to reducing asset purchases in the near-future.
Yahoo said it will acquire blogger service Tumblr for about $1.1 billion in cash. The deal marks the largest acquisition of a social networking company in years, exceeding Facebook's $1 billion purchase of Instagram last year.
Also on the M&A front, Warner Chilcott advanced after Actavis confirmed it will acquire the pharmaceutical company in a stock-for-stock transaction valued at $5 billion.
And Pactera Technology International skyrocketed more than 30 percent after a Blackstone affiliate proposed to take the IT consulting company private.
In the final stretch of earnings season, 27 S&P 500 companies are due to post results this week.
Campbell Soup climbed after the soup maker posted higher-than-expected earnings and lifted its full-year forecast, thanks to improved sales.
Urban Outfitters and TiVo are slated to report after the closing bell.
So far, 93 percent of S&P 500 companies have reported quarterly results, with 67 percent of firms topping earnings expectations and 24 percent missing forecasts, according to data from Reuters. If all remaining companies report earnings in line with estimates, earnings will be up 4.8 percent from last year's first quarter.
Precious metals were in focus earlier in the day, after spot silver prices dropped by as much as 9 percent in Asian trading and gold prices fell 2 percent.
"There has been chatter suggesting the outsized move was driven by a margin call and subsequent liquidation by an investor. Notably, gold is poised to close weaker for the tenth time in 11 sessions, and is now trading at similar levels as the April lows ($1345 per ounce)," said Deutsche Bank's Jim Reid in a research note on Monday.
—By CNBC's JeeYeon Park. Follow JeeYeon on Twitter: @JeeYeonParkCNBC
Coming Up This Week:
MONDAY: Fed's Evans speaks; Earnings fromUrban Outfitters, TiVo
TUESDAY: Fed's Bullard speaks, Fed's Dudley speaks, 2-yr note auction, Apple's Cook on the Hill, JPMorgan shareholder mtg, Xerox shareholder mtg; Earnings from Home Depot, Medtronic, Vodafone, Best Buy, Saks, TJX, NetApp
WEDNESDAY: Mortgage applications, existing home sales, Ben Bernanke speaks, oil inventories, 5-yr note auction, FOMC minutes, Boeing analyst day, Royal Caribbean shareholder mtg, Travelers shareholder mtg; Earnings from Lowe's, Target, Staples, Toll Brothers, Hewlett-Packard, L Brands, PetSmart
THURSDAY: Fed's Bullard speaks, jobless claims, PMI manufacturing index flash, FHFA home price index, natural gas inventories, Kansas City Fed survey, 7-yr note auction, Fed balance sheet/money supply, Goldman Sachs annual mtg, L Brands shareholder mtg, McDonald's shareholder mtg, Time Warner shareholder mtg; Earnings from Dollar Tree, Gamestop, Ralph Lauren, Sears Holdings, Gap, Marvell Tech, Ross Stores, Aeropostale, Pandora
FRIDAY: Durable goods orders; Earnings from Abercrombie & Fitch
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