Chair of the firm, Mr. Karp has achieved national prominence as both a litigator and corporate adviser. Mr. Karp has extensive experience defending financial institutions and other companies in "bet the company" litigations and regulatory matters. Prior to being named chair of Paul, Weiss, Mr. Karp chaired the firm's Litigation Department.

Mr. Karp has been profiled as one of the leading lawyers in the United States by The Wall Street Journal, The New York Times, The Financial Times, The American Lawyer, Chambers, The Lawyer (U.K.), Crain’s, The National Law Journal, The New York Law Journal, Lawdragon, Best Lawyers in America, Legal 500, Euromoney Institutional Investors, Best of the Best USA, Law360, and Benchmark/Institutional Investor.

In 2003, Mr. Karp was profiled in The American Lawyer as one of the 45 leading lawyers in the United States under the age of 45. Mr. Karp's successful representation of financial institutions in complex litigations and regulatory matters was featured in a January 2010 American Lawyer story, "Wall Street Bailout," and in a January 2006 American Lawyer cover story, "The Lifesavers," in which Paul, Weiss was selected as the best litigation firm in the United States. In 2011, Mr. Karp was named one of the Most Influential People in the Boardroom by the National Association of Corporate Directors. Also in 2011, Lawdragon named Mr. Karp its “Lawyer of the Year” and Chambers selected him as the only “Star” in its Nationwide Securities Litigation category. He was also named "Litigator of the Week" in the November 11, 2011 issue of Am Law Litigation Daily in connection with the firm's successful defense of Citigroup in an arbitration brought before the AAA International Centre for Dispute Resolution by the Abu Dhabi Investment Authority (ADIA). Mr. Karp was named 2012 “Securities Lawyer of the Year” by Best Lawyers.

Currently, Mr. Karp is lead counsel for Citigroup in numerous matters, including, among others, its subprime, credit crisis and mortgage-related litigations and regulatory matters; its auction rate securities litigations and regulatory matters; its Lehman-related litigations; its failed investment litigations and regulatory matters; its Enron-related litigations and regulatory matters; its Parmalat-related litigations; its research analyst litigations; and a nationwide employment discrimination class action. Mr. Karp quarterbacked the successful defense of Citigroup in (i) the multi-billion-dollar Terra Firma fraud trial arising out of Terra Firma’s 2007 acquisition of EMI, and (ii) the multi-billion-dollar arbitration brought by Abu Dhabi Investment Authority, arising out of its December 2007 $7.5 billion investment in Citigroup. Mr. Karp also recently represented Citigroup in connection with the Financial Crisis Inquiry Commission investigation into the causes of the financial crisis.

In addition, Mr. Karp is lead counsel for JPMorgan in several matters, including the litigations and regulatory matters arising out of Bear Stearns' March 2008 collapse, various subprime, credit-crisis and mortgage-related litigations, and the Financial Crisis Inquiry Commission investigation into the causes of the financial crisis. Mr. Karp is representing Bank of America in several matters, including the litigations and regulatory matters arising out of Bank of America's 2008 merger with Merrill Lynch. Mr. Karp is representing Bank of New York in several matters, including the litigations and regulatory matters arising out of the bank’s foreign exchange standing instruction orders. Mr. Karp also is representing syndicates of Wall Street underwriters in several securities class action litigations, including, among others, class actions arising out of the $25 billion GM/GMAC bond offering and the $20+ billion AIG bond offering, as well as class actions arising out of the Ambac and American Home Mortgage bond offerings. In addition, Mr. Karp is lead counsel for the National Football League in the pending litigations alleging that the League is responsible for concussion-related injuries sustained by its former players.

Currently, Mr. Karp is representing Citigroup, JPMorgan/Bear Stearns, Bank of America/Merrill Lynch, Wells Fargo/Wachovia, Morgan Stanley, HSBC, Goldman Sachs, Bank of New York Mellon, UBS, Apollo, Deloitte, Ernst & Young, the National Football League, MacAndrews & Forbes, ING, Ericsson, Newmont Mining, Sumitomo, SICPA, Hexion, Vivendi, Scottish Power, BB&T, Eton Park, Oppenheimer, OneWest Bank, CIM Group, Fortress, Dresser-Rand and Repsol YPF, S.A., among others, in significant securities, commercial and regulatory matters. Mr. Karp also is handling a range of litigations and special projects for Major League Baseball, Sotheby's and Alcoa.

Mr. Karp is a frequent lecturer and writer, having spoken at more than 350 conferences and published more than 400 articles on business litigation and securities law issues. Mr. Karp has lectured on business litigation and securities litigation at Harvard Law School and Columbia Law School. For the past 26 years, Mr. Karp has written a monthly column for the New York Law Journal, "Second Circuit Review," which analyzes developments in the Second Circuit Court of Appeals, and is a frequent contributor to The Harvard Law School Forum on Corporate Governance and Financial Regulation.

Mr. Karp is active in the community, serving as a director/trustee of the Legal Action Center, the Riverdale Country School, The Partnership for New York City, the Harvard Law School Leadership Council, Practicing Attorneys for Law Students Program, Inc., American Friends of Hebrew University, the New York Bar Foundation, the Program Advisory Board of the Brennan Center for Justice, the Best Lawyers Advisory Board, the Economic Club of New York, the Federal Bar Council Second Circuit Inn of Court, the Union College President’s Council, and the United States Supreme Court Historical Society. Mr. Karp also is a founding member of the PriceWaterhouse Leaders Council examining financial services industry regulatory reform.

Recently, Mr. Karp was awarded the Extraordinary New Yorker Award by the JBFCS, the Torch of Learning Award by American Friends of Hebrew University and The Arthur Liman Public Interest Award by the Legal Action Center.