Louisiana-Pacific Corp. (NYSE: LPX) has agreed to acquire Ainsworth Lumber Co. (TSX: ANS). The deal is valued at US$1.1 billion, or C$3.76 per share (30% premium). Sellers include Brookfield Asset Management, whichholds a 54% stake in Ainsworth. www.ainsworthengineered.com

Mail.ru has sold its remaining Facebook (Nasdaq: FB) stake, around 14.2 million shares, for approximately $525 million. The Russian company also had approximately $745 million worth of Facebook shares during last year’s Facebook IPO. Its original investment was $200 million.www.mail.ru

Madison Square Garden Co. (Nasdaq: MSG) has invested $175 million to help Irving Azoff launchAzoff MSG Entertainment, which will include talent management, performing rights, music publishing and a blogger management unit.

American Family Insurance has agreed to acquire Homesite Group Inc., a Boston–based direct homeowners insurer. No financial terms were disclosed. Sellers include Metalmark Capital,Alleghany Corp. and The Plymouth Rock Co. www.amfam.com

Platinum Equity and The Gores Group have sold Alliance Entertainment, a Coral Springs, Fla.-based music, video and accessories distributor, to Super D, an Irvine, Calif.-based music and video wholesaler. No financial terms were disclosed. www.sdcd.com

EP Energy has filed for a $100 million IPO. It plans to trade on the NYSE under ticker symbol EPE. The company reports $87 million in net income on $850 million in revenue for the first six months of 2013, compared to a $256 million loss on $803 million in revenue for the year-earlier period. EP Energy was acquired from El Paso Corp. last year for nearly $7.2 billion by Apollo Global Management, Access
Industries, Riverstone Holdings and Korea National Oil Corp. www.epenergy.com

Five Prime Therapeutics Inc., a South San Francisco-based developer of protein therapeutics that block disease processes, has set its IPO terms to 4 million shares being offered at between $12 and $14 per share. It would have an initial market cap of approximately, were it to price in the middle of its range. The company plans to trade on the Nasdaq under ticker symbol FPRX, with Jefferies, BMO Capital Markets and Wells Fargo serving as lead underwriters. Shareholders include Pfizer (10.1% pre-IPO stake), Kleiner Perkins (6.7%), TPG Capital (6.7%), Versant Ventures (6.7%), HealthCap (6.7%), Advanced Technology Ventures (6.7%), Domain Associates (6.7%), GlaxoSmithKline (4.7%) and Johnson & Johnson (3.9%).  www.fiveprime.com

Macrogenics Inc., a Rockville, Md.-based developer of monoclonal antibody-based therapeutics for the treatment of cancer and autoimmune diseases, has filed for a $60 million IPO. It plans to trade on the Nasdaq under ticker symbol MGNX, with BoA Merrill Lynch serving as lead underwriter. Shareholders include TPG Capital, Alta Partners, InterWest Partners, MPM Capital, Caisse de dépôt et placement du Québec and Ventures West.  www.macrogenics.com

Surgical Care Affiliates Inc., a Deerfield, Ill.-based provider of surgical care optimization solutions, has filed for a $100 million IPO. It plans to trade on the Nasdaq, with JPMorgan and Citigroup serving as lead underwriters.The company reports $42.2 million of net income on nearly $389 million of revenue for the first six months of 2013. TPG Capital acquired SCA in 2007 from HealthSouth for $945 million. www.scasurgery.com

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