Private equity firm Avista Capital Partners announced today it has signed a definitive agreement to acquire Top-Co Inc., a privately-held, designer and manufacturer of specialized casing cementing products used in the drilling and completion of oil, natural gas and geothermal wells. Terms of the transaction, which is expected to close in the second quarter of 2012, were not disclosed. 

Environmental Drilling Solutions, LLC, a provider of solids control, cuttings processing and zero discharge services, has received a growth equity investment from Element Partners and CSL Capital Management.  

Dahlman Rose & Co., LLC announced today that its parent company has entered into a definitive agreement to sell an additional $10 million of equity to affiliates of Lovell Minnick Partners LLC, a private equity firm that specializes in the global financial services industry.

Argentina-based Valle Silencioso SA, a company managed by Sophia Capital, has acquired 50% of the outstanding shares of SO-4 Ltd. from 4D Global Energy Investments Plc.

Calgary-based Encana Corporation (TSX, NYSE: ECA) has reached an agreement with Toyota Tsusho Wheatland Inc., a subsidiary of Toyota Tsusho Corporation, that will see the Japanese company invest approximately C$602 million (US$608 million) to acquire a 32.5% royalty interest in natural gas production from a portion of Encana’s coalbed methane (CBM) resource play.

Toronto-based Scotiabank said April 18 that it has closed the acquisition by Scotia Capital Inc. of Howard Weil Incorporated, a US energy investment boutique with major offices in New Orleans and Houston. Terms of the transaction were not disclosed.

High oil prices continue to support stable credit quality for US exploration and production (E&P) companies this year, according to Standard & Poor’s.

How will the Volcker Rule affect oil and gas companies? The Volcker rule is a specific section of the Dodd-Frank Wall Street Reform & Consumer Protection Act intended to restrict certain kinds of speculative investments that do not benefit their customers.

A class-action lawsuit has been filed against Houston-based CARBO Ceramics (NYSE: CRR) on behalf of investors who bought the company’s stock between Oct. 27, 2011, and Jan. 26, 20-12.