Warren A. Koshofer

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Warren A. Koshofer

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Banking & Financial Services
Consumer Products
Commercial & Business Litigation
Regulatory & Administrative Law

New York

Bar & Court Admissions

  • State Bar of California
  • State Bar of New York
  • State Bar of New Jersey
  • State Bar of Pennsylvania
  • U.S. Court of Appeals for the Third Circuit
  • U.S. Court of Appeals for the Ninth Circuit
  • U.S. District Court for the Eastern, Central, and Southern Districts of California
  • U.S. District Court for the Southern, Eastern, and Northern Districts of New York
  • U.S. District Court for the District of New Jersey

Industry Association

  • The Risk Management Society (RIMS)

Professional Affiliations

  • American Bar Association
  • California State Bar Association
  • New Jersey State Bar Association
  • New York State Bar Association

Community Involvement

  • Make a Wish Foundation
  • March of Dimes
  • United Way
  • Local Youth Football


  • Rutgers University School of Law, J.D.
  • Rutgers University, B.A.

Warren Koshofer is a partner in M&R’s New York office and member of the firm’s Commercial & Business Litigation Practice Group. Warren focuses his practice on business, commercial, environmental, insurance, and real estate related litigation. He also routinely handles due diligence, indemnification, and risk management related analyses for mergers and acquisitions which involve commercial or industrial real estate assets and potential environmental liabilities.

Among the cases Warren handles are those in involving the oil and gas, chemical, consumer product manufacturing, and financial spaces, including contract negotiations and disputes, intra-company disputes, environmental, insurance coverage and defense, toxic tort defense, real estate transactions, and due diligence and indemnification relating to company mergers and acquisitions. Warren does so on behalf of clients—including Fortune 100 companies, partnerships, and high-profile individuals—at the state and federal trial and appellate court levels, as well as before administrative law courts, regulatory agencies, and in alternative dispute resolution forums across the country.

Of note, Warren has orchestrated several landmark victories in the insurance, environmental, manufacturing, financial, and hospitality industries, as well as in the oil, gas, chemical and energy sectors in litigation alleging, among other things, toxic exposures, product defects, and Proposition 65 violations. Of note, Warren is regularly called upon to tackle disputes that are at the intersection of law and science.

Business Litigation: Represented a cannabis-related business in wrestling control of its dispensary operations back from minority partners and obtaining favorable decisions on the client’s super-majority ownership rights.
CERCLA Defense: Successfully represented a metal plating operation in defense of CERCLA contribution claims brought by a neighboring property owner who, after aggressive litigation and receipt of counterclaims filed on the clients’ behalf, settled with the client for a “walk-away” dismissal of all claims.
Consumer Litigation (Insurance): Represented a large international insurance company sued by a public company policyholder contending that an insurance product was illusory, illegal and evidenced a pattern and practice justifying over $100M in damages. Devised a defense strategy that included filing suit against the policyholder for failing to pay certain policy premiums. Through litigation, secured a dismissal of the plaintiff’s lawsuit and recovered approximately $5M on client’s behalf.
Corporate Dispute: Successfully represented a managing member of an LLC by defeating all claims brought by other members of the LLC which alleged that the managing member misappropriated corporate opportunities and violated fiduciary duties. The client was completely vindicated in defense of all claims.
Due Diligence: Conducted due diligence on behalf of banks and other financial investors associated with contemplated new investments or loans, particularly with respect to environmental and litigation risks.
Environmental Defense: Successfully defended a client against action by the USEPA, which filed a complaint seeking millions of dollars in penalties for alleged regulatory violations. The USEPA alleged the client operated a plant that leaked a hazardous substance into the air before being shut down by USEPA. Choosing to push back against the proposed penalties versus a merit-based challenge, the dispute was favorably resolved for $5,000.
Insurance Coverage (Bad Faith Defense): Represented a prominent insurance company in the defense of an arbitration proceeding where the insured, under CGL insurance policies issued by the client, sought the return of several million dollars paid by the insured for, among other things, deductible obligations. After an aggressive defense, the case ultimately settled at mediation with the insured paying the insurer several million dollar.
Insurance Coverage (Policyholder): Represented product manufacturers in lawsuits with their liability insurers arising out of environmental and toxic tort claims. Overcame numerous challenges by the insurers, including claims that underlying layers of coverage were not exhausted and occurrences did not take place in particular policy years, to drive the insurers to the settlement table to fund environmental cleanup and defend toxic tort actions.
Proposition 65: Represented product manufacturers in California Proposition 65 cases relating to various products, including a bicycle manufacturer defending claims that the cables on its bicycles were subject to Prop 65 disclosures.
Securities Fraud Defense: Represented an investment banking firm in defense of a securities fraud case alleging hundreds of millions of dollars of losses stemming from an alleged pump and dump stock scheme.
Toxic Tort Defense: Represented a chemical manufacturer in the defense of more than 80 separate toxic tort cases filed by teachers and students at an elementary school which neighbored a plating operation site where the client’s chemicals were allegedly used. Led the defense to a very favorable settlement on client’s behalf.
  • AV® Preeminent Peer Review Rating, Martindale-Hubbell
  • New York “Super Lawyers
  • California “Super Lawyers”
  • Who’s Who in Law, Marquis