Lightower Fiber Networks, the premier metro fiber and bandwidth provider in the Northeast, and Sidera Networks, the leading provider of tailored, high-capacity communications services to large enterprise, carrier and data center customers, announced that they have signed a definitive agreement for a transaction valued at over $2 billion led by Berkshire Partners, a Boston-based investment firm, and management, to acquire and merge both companies. M/C Partners and Pamlico Capital acquired Lightower from National Grid plc in August 2007. Pamlico Capital, a significant Lightower investor, and ABRY Partners, a significant Sidera investor, will remain as investors in the new company. The combined company will be led by current Lightower CEO, Rob Shanahan. The merger is pending regulatory approval and is expected to close in the second quarter of 2013.