Oak Hill Capital Partners has agreed to sell Security Networks LLC, a West Palm Beach, Fla.–based home security solutions provider, to Monitronics International, a subsidiary of Ascent Capital Group Inc. (Nasdaq: ASCMA). The deal is valued at around $507 million, including $487.5 million in cash. www.securitynetworks.net
QLess Inc., an Altadena, Calif.–based mobile queuing solution, has agreed to acquire Supalocal, a London-based virtual queue management company. No financial terms were disclosed. www.qless.com
Noble Group Inc. (Singapore: N21) is considering a bid for Australian iron-ore miner Western Desert Resources Ltd. (ASX: WDR), according to the WSJ. WDR has a market cap of around A$235 million.www.thisisnoble.com
Western Digital Corp. (Nasdaq: WDC) has acquired VeloBit, a Lincoln, Mass.–based provider of storage I/O optimization software. No financial terms were disclosed. VeloBit had raised VC funding from Fairhaven Capital Partners and Longworth Venture Partners. www.velobit.com
Cellular Dynamics International Inc., a Madison, Wis.-based maker of human-induced pluripotent stem cells and tissue cells, has set its IPO terms to 3.85 million shares being offered at between $12 and $14 per share. It would have an initial market cap of around $205 million, were it to price in the middle of its range. The company plans to trade on the Nasdaq under ticker symbol ICEL, with J.P. Morgan serving as lead underwriter. Cellular Dynamics has raised more than $100 million in VC funding since 2004, from Tactics II Stem Cell Ventures (56.4% pre-IPO stake), Sixth Floor Investors (17.3%), Equity Group Investments (7.9%) and G Force Investments. www.cellulardynamics.com
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