Ahead of market open, shares were up 39.3% to $9.86.
In a statement, privately-held Birch said the combination creates a "nationwide communications, cloud and managed services provider with approximately $700 million in annual revenue and approximately 200,000 business customers located in all 50 states."
Cbeyond stockholders will receive between $9.97 and $10 a share, the former a 56.8% premium to its stock price on November 5, 2013.
"After a thorough six-month strategic review process in which we evaluated a wide range of alternatives in addition to a sale, the Cbeyond board of directors determined that this all-cash transaction with Birch maximizes stockholder value through an attractive premium," said Cbeyond chairman and CEO James Geiger in a statement.
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