Cozen O’Connor: Wischhusen, Carl B.

Carl B. Wischhusen


New York

(212) 883-4991

(646) 588-1376

Carl B. Wischhusen has extensive experience in litigation, patent prosecution, and due diligence in the electrical and mechanical fields. His current practice includes:

Preparation of claim construction briefs, invalidity contentions, and other litigation filings. Performing validity and infringement analyses in support of litigation. Preparation of briefs and responses for inter partes reviews. Preparation of invalidity, patentability, and freedom-to-operate opinions. Counseling clients on prosecution strategy, design-around solutions, and patent licensing.

Performing day-to-day work on all aspects of prosecution for U.S., PCT, and foreign patent applications for clients such as Orange (formerly France Telecom), Siemens, Osram, and Konica-Minolta. Preparing patent applications, amendments, reexams, reissues, appeal briefs, and other prosecution-related papers, and conduct interviews.

Performing intellectual property due diligence in support of business and investment deals, including analysis of patent portfolio for ownership, validity, and scope of coverage. Performing analysis of existing and proposed products for freedom-to-operate. Conducting review of IP-related representations and warranties and other IP-related portions of asset purchase and licensing contracts.


Performed pre-litigation research and analysis for various litigation clients, including Intel, Research In Motion, Apple, STMicroelectronics, and State Street Bank. Analyzed portfolios of pending patent applications to evaluate strength and propose prosecution strategies in view of potential future litigation. Performed infringement analysis on competitors’ products and invalidity analysis on competitors’ patents. Prepared claim construction and technology tutorial materials for Markman hearings. Researched and interviewed expert witnesses.

Managed patent prosecution group, including associates and technology specialists, handling portfolio of electrical and biomedical engineering technologies for Columbia University. Managed patent prosecution for other clients, including Endeca, State Street Bank, and Constar. Performed patent prosecution, opinion work, client counseling and litigation support in the electrical, business/financial, and mechanical fields. Clients included American Express and Michelin, among a wide range of large corporations, small companies and start-up companies.


  • Georgetown University Law Center, J.D., 2000
  • Virginia Polytechnic Institute and State University, B.S.E.E.
  • Johns Hopkins University, M.S.E.E.
  • New York
  • United States Patent and Trademark Office
  • U.S. District Court -- Eastern District of New York
  • U.S. District Court -- Southern District of New York