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  1. Professionals

Walter M. Berger

Partner

Chair, Houston Litigation Practice

Houston

+1 713-651-2611

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Chair of Houston’s Litigation Practice, Walter (Casey) focuses his practice on complex commercial business litigation and trial practice in securities, antitrust, consumer fraud, and class action defense matters. He has resolved billions of dollars in claims and disputes for his clients in just the past few years.

Casey’s range of experience includes defense of corporations, officers, and directors in private securities litigation, derivative actions, and enforcement proceedings; the defense of companies in antitrust and consumer fraud class actions; and the representation of major corporations in domestic and international arbitration. Casey has significant experience in all phases of trial and appellate practice in both state and federal courts, as well as arbitration proceedings throughout the United States and abroad. 

Key Matters

  • Lead trial counsel for the former CEO, CFO and founder of Alta Mesa Resources, Inc, a publicly traded oil and gas exploration and production company, in a securities class action and opt-out suit alleging securities and state law violations arising from a deSPAC transaction that was the first of its kind to go to trial. Claims were in excess of $1 Billion and the case settled favorably for our clients before closing arguments. Also handled the related bankruptcy claims against our clients. 
  • Lead counsel for a leading oilfield services company as a plaintiff against defendant E&P company in a breach of contract and fraud case arising out of a joint venture to develop oil and gas assets in the Powder River Basin. Obtained an 8-figure settlement for our client. 
  • Lead litigation counsel for the defendant buyer and related affiliates in merger litigation arising out of the US$500M acquisition of a major grocery store chain. Successfully negotiated an agreement that allowed the merger to close on schedule, and led the defense of the combined company in the post-closing litigation that continued thereafter. The class action was eventually settled on favorable terms. Successfully defended the company in the follow-on appraisal arbitration for those that opted out of the settlement, resulting in an award of damages to our clients.
  • Lead litigation counsel for private equity firm in bankruptcy litigation and related adversary proceedings arising out of the US$400M+ acquisition of a subprime mortgage lender that subsequently went bankrupt during the financial collapse in 2009. Led the insurance coverage negotiations and successfully resolved all of the claims against the represented defendants on favorable terms.
  • Lead counsel in the defense of an oilfield services company in an ICC Arbitration arising out of the termination of an exclusive dealer. Case was settled on favorable terms on the last day of the arbitration hearing.  
  • Successfully defended a syndicate of bank underwriters in a putative securities class action involving Section 11 of the Securities Act of 1933 and stemming from alleged misrepresentations relating to the IPO of a nationwide restaurant group. The case settled on favorable terms to our clients.
  • Represented a global financial institution in a nationwide class action in which plaintiff alleged the financial institution’s automatic payment system was crediting mortgage payments late in order to obtain more interest than the bank was entitled to under the mortgage loan documents.
  • Acted as lead counsel for defendant, an oil and gas equipment and services provider, in several consolidated shareholder class actions brought in Texas State Court seeking to enjoin the client’s US$5.5B acquisition of one of its competitors. The matters were resolved on favorable terms and the merger proceeded to consummation.
  • Represented a national services provider and its subsidiaries in a series of state court consumer fraud class actions across the country challenging the defendants’ pricing and notice practices. The cases were either dismissed on the pleadings or settled for less than nuisance value. No contested plaintiff classes were ever certified. 
  • Defended a European manufacturing firm in an antitrust class action arising out of an alleged international price-fixing and bid-rigging cartel in the marine hose industry.
  • Successfully defended a Fortune 200 company in an important case of first impression under state securities laws involving damages in excess of US$200M. Obtained a summary judgment verdict for the client, and successfully defended that judgment on appeal. 
  • Successfully defended a major international waste management company and its subsidiaries in several breach of contract and securities fraud actions in federal and state courts across the country. Damages claims ranged from US$5M to more than US$100M, and cases involved use of the multidistrict litigation transfer procedures. Obtained several dismissals in advance of trial, and successfully defended several dismissals on appeal to the U.S. Court of Appeals for the Fifth Circuit. 
  • Represented a major pharmaceutical company in a securities fraud class action filed in the Southern District of New York. The case was settled prior to the court’s ruling on class certification.
  • Defended a Fortune 200 company in an ICC arbitration that was tried in New York in 2005; claims were in excess of US$100M and involved French, U.S., and Latin American assets.
  • Served as lead counsel for venture capital firm and its portfolio technology companies in several employment, executive compensation, securities, and breach of contract disputes.
  • Successfully defended U.S. parent and Australian subsidiary in a breach of contract and tortious interference action related to a major construction dispute in Australia. The case involved proceedings in both state and federal court. Obtained effective dismissal under the International Abstention Doctrine, and defended that result in the Fifth Circuit.
  • Represented underwriters Credit Suisse Securities USA LLC, Robert W. Baird & Co., Inc., Lazard Capital Markets LLC, and others in a putative securities class action case involving Section 11 of the Securities Act of 1933 and stemming from alleged misrepresentations relating to the IPO of Ignite Restaurant Group. The case settled favorably for our clients.

Casey was recognized in the 2025 edition of The Best Lawyers in America® for Securities Litigation.  He was also recognized by Legal 500 US for Securities Litigation in 2018 and as a “Key Lawyer” in the area of Energy Litigation: Oil and Gas (2023–2024). He was recognized in Lawdragon’s  “500 Leading Energy Lawyers” for Oil and Gas Litigation (2024–2025) and the Lawdragon’s  “Green 500 Leading Environmental Lawyers” in 2025.  He was named a “Texas Litigation Star” in Benchmark Litigation US (2015–2025) and was selected repeatedly as a “Rising Star” for Business Litigation by Texas Monthly. He is part of the group awarded the “2015 Team of the Year” in Cartel Defense by The Legal 500 US.

Casey is a member of the American Bar Association and the Houston Young Lawyers Association. He has served on the Board of Directors for the Litigation Section of the Houston Bar Association. 

Capabilities

Litigation/Trials
Securities, M&A & Corporate Governance Litigation
Antitrust/Competition
Commercial Litigation & Disputes
Class Actions & Group Litigation
International Arbitration
Financial Services Litigation
Financial Services
Medical Devices
Energy
Oil & Gas

Key Matters

  • Lead trial counsel for the former CEO, CFO and founder of Alta Mesa Resources, Inc, a publicly traded oil and gas exploration and production company, in a securities class action and opt-out suit alleging securities and state law violations arising from a deSPAC transaction that was the first of its kind to go to trial. Claims were in excess of $1 Billion and the case settled favorably for our clients before closing arguments. Also handled the related bankruptcy claims against our clients. 
  • Lead counsel for a leading oilfield services company as a plaintiff against defendant E&P company in a breach of contract and fraud case arising out of a joint venture to develop oil and gas assets in the Powder River Basin. Obtained an 8-figure settlement for our client. 
  • Lead litigation counsel for the defendant buyer and related affiliates in merger litigation arising out of the US$500M acquisition of a major grocery store chain. Successfully negotiated an agreement that allowed the merger to close on schedule, and led the defense of the combined company in the post-closing litigation that continued thereafter. The class action was eventually settled on favorable terms. Successfully defended the company in the follow-on appraisal arbitration for those that opted out of the settlement, resulting in an award of damages to our clients.
  • Lead litigation counsel for private equity firm in bankruptcy litigation and related adversary proceedings arising out of the US$400M+ acquisition of a subprime mortgage lender that subsequently went bankrupt during the financial collapse in 2009. Led the insurance coverage negotiations and successfully resolved all of the claims against the represented defendants on favorable terms.
  • Lead counsel in the defense of an oilfield services company in an ICC Arbitration arising out of the termination of an exclusive dealer. Case was settled on favorable terms on the last day of the arbitration hearing.  
  • Successfully defended a syndicate of bank underwriters in a putative securities class action involving Section 11 of the Securities Act of 1933 and stemming from alleged misrepresentations relating to the IPO of a nationwide restaurant group. The case settled on favorable terms to our clients.
  • Represented a global financial institution in a nationwide class action in which plaintiff alleged the financial institution’s automatic payment system was crediting mortgage payments late in order to obtain more interest than the bank was entitled to under the mortgage loan documents.
  • Acted as lead counsel for defendant, an oil and gas equipment and services provider, in several consolidated shareholder class actions brought in Texas State Court seeking to enjoin the client’s US$5.5B acquisition of one of its competitors. The matters were resolved on favorable terms and the merger proceeded to consummation.
  • Represented a national services provider and its subsidiaries in a series of state court consumer fraud class actions across the country challenging the defendants’ pricing and notice practices. The cases were either dismissed on the pleadings or settled for less than nuisance value. No contested plaintiff classes were ever certified. 
  • Defended a European manufacturing firm in an antitrust class action arising out of an alleged international price-fixing and bid-rigging cartel in the marine hose industry.
  • Successfully defended a Fortune 200 company in an important case of first impression under state securities laws involving damages in excess of US$200M. Obtained a summary judgment verdict for the client, and successfully defended that judgment on appeal. 
  • Successfully defended a major international waste management company and its subsidiaries in several breach of contract and securities fraud actions in federal and state courts across the country. Damages claims ranged from US$5M to more than US$100M, and cases involved use of the multidistrict litigation transfer procedures. Obtained several dismissals in advance of trial, and successfully defended several dismissals on appeal to the U.S. Court of Appeals for the Fifth Circuit. 
  • Represented a major pharmaceutical company in a securities fraud class action filed in the Southern District of New York. The case was settled prior to the court’s ruling on class certification.
  • Defended a Fortune 200 company in an ICC arbitration that was tried in New York in 2005; claims were in excess of US$100M and involved French, U.S., and Latin American assets.
  • Served as lead counsel for venture capital firm and its portfolio technology companies in several employment, executive compensation, securities, and breach of contract disputes.
  • Successfully defended U.S. parent and Australian subsidiary in a breach of contract and tortious interference action related to a major construction dispute in Australia. The case involved proceedings in both state and federal court. Obtained effective dismissal under the International Abstention Doctrine, and defended that result in the Fifth Circuit.
  • Represented underwriters Credit Suisse Securities USA LLC, Robert W. Baird & Co., Inc., Lazard Capital Markets LLC, and others in a putative securities class action case involving Section 11 of the Securities Act of 1933 and stemming from alleged misrepresentations relating to the IPO of Ignite Restaurant Group. The case settled favorably for our clients.

Credentials

Education

Casey received his B.A., cum laude, from Pomona College in 1992, where he also attended Cambridge University on an international studies program in 1991. He received his J.D., with honors, from the University of Texas School of Law in 1996.

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    Capabilities

    Litigation/Trials
    Securities, M&A & Corporate Governance Litigation
    Antitrust/Competition
    Commercial Litigation & Disputes
    Class Actions & Group Litigation
    International Arbitration
    Financial Services Litigation
    Financial Services
    Medical Devices
    Energy
    Oil & Gas
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