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What: Shares of retail options brokerage optionsXpress Holdings (Nasdaq: OXPS) climbed 15% on Monday after Charles Schwab (NYSE: SCHW) said it would buy the company for about $1 billion.

So what: The all-stock deal values optionsXpress at $17.91 per share and represents a 17% premium to its Friday closing price. The booming popularity of options trading in the U.S. makes the move an obvious one for Schwab, especially considering that its option-trading customers are about six times as active and tend to be longer-standing than other clients.

Now what: The acquisition, in which each optionsXpress share will be exchanged for 1.02 shares of Schwab, is expected to close in the third quarter. Schwab sees $80 million in revenue and synergies arising from the deal, as well as a modest profit boost in the first year as a combined company. Of course, with the trend toward nontraditional asset classes likely to continue, the long-term upside that Schwab gains is what's most appealing.   

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