Apax Partners “is likely to wind up as the largest single equity holder” in Cengage Learning, an Apax portfolio company that currently is in Chapter 11 bankruptcy protection, according to LBO Wire. Apax is expected to see around 97% of its equity investment wiped out, but the firm also acquired much of Cengage’s first-lien debt prior to the bankruptcy, which could leave it with around a 19% stake in the restructured company. www.apax.com

The Cortec Group is in talks to acquire Weiman Products LLC, a Gurnee, Ill.–based maker of buy cleaning and polishing products, from The Randolph Group, according to an FTC filing.www.weiman.com

Lynx Equity has acquired Majestic Media Ltd., a Canadian developer of custom social media campaigns and applications. No financial terms were disclosed. www.majesticmedia.ca

Riverstone Holdings has committed $200 million to help form Abaco Energy Technologies, a new Houston-based company that will acquire, integrate and develop energy manufacturing and service businesses. It is led by Ken Babcock  and Roger Rivet, the former CEO and CFO, respectively, of former Riverstone portfolio companies Titan Specialties and International Logging.www.riverstonellc.com

Sheridan Legacy Group has acquired Progenicare, an Austin, Texas-based provider of autologous stem cell therapies to orthopedic surgeons and hospitals across the Western U.S. No financial terms were disclosed. www.sheridanlegacy.com

Sun Capital Partners has acquired a controlling stake in Demilec Group, a Canadian maker and distributor of spray polyurethane foam insulation and related products. www.demilec.com

Baird Capital has acquired Kason Corp., a Millburn, N.J.-based maker of industrial filtration and separation processors. No financial terms were disclosed. www.BairdCapital.com

Insight Venture Partners has acquired a majority stake in Unitrends, a Columbia, S.C.–based
provider of backup, archiving, instant recovery and disaster recovery solutions. No financial terms were disclosed. The company had raised VC funding from Charleston Angel Partners, eCentury Capital Partners, Harbert Venture Partners, MMV Financial, Paladin Capital Group, The Aurora Funds and The Trelys Funds. www.unitrends.com

Ontario Teachers’ Pension Plan has acquired Busy Bees Nursery Group, an operator of 213 childcare facilities in the UK, from Knowledge Universe. No financial terms were disclosed.www.busybeeschildcare.co.uk

TPH Partners has formed Elk Meadows Resources LLC, a Denver-based upstream energy company focused on the acquisition and development of onshore oil and gas properties across the Permian Basin and the Rockies. No financial terms were disclosed. www.elkmeadowsenergy.com