Mark G. Hanley, JD, MBA, BSEE

I believe our clients benefit from the real-world engineering experience that our practitioners bring to the firm. This experience enables us to interface efficiently with inventors and provides a practical and business-minded foundation for all of our work.

I represent numerous large corporate clients involved in a diverse range of electrical, software, and mechanical technologies, and I have extensive experience in all aspects of patent prosecution and counseling including freedom-to-operate analyses, non-infringement and invalidity opinions, and reexaminations.

Prior to practicing law, I was a design engineer specializing in switching power supplies; analog circuitry; and a variety of pressure, temperature, and position transducers. I am also an inventor on several patents relating to piezoelectric biomorphs.

In 2023, I was Recommended for Patent Prosecution by the IAM Patent 1000 and was designated a Patent Star in the United States (national) and Illinois from Managing IP’s IP Stars, an annual guide to the top intellectual property attorneys in Illinois and nationwide. IP Stars Read Here

James A. Flight, JD, BSEE

As one of the founding members of HFZ, I have over 30 years’ experience in patent litigation, patent prosecution and patent counseling. My experience representing clients includes a diverse range of technologies, including software, telecommunications, analog and digital circuitry, semiconductor structures and fabrication techniques, microprocessor architecture, FPGA technology, virtual private networking, internet technologies, audience measurement technologies, cloud computing, virtualization, data warehousing, network security, memory architectures, green technologies, safety products, dock safety equipment, industrial doors, ventilation, surgical equipment, and child care products.

My focus is on our client’s business objectives. Our ultimate goal is to provide counsel and patent prosecution strategies that advance our client’s agenda. This is best achieved in a long-term relationship that fosters an in-depth understanding of our client’s business and the competitive landscape in which they operate. On the prosecution side, this level of commitment ensures we do not just secure patent claims; we issue claims that are tailored for ready enforcement when the need arises.

I’m actively involved in defensive and offensive patent issues including ex parte and inter partes reexaminations, reissues, Public Use proceedings, European opposition proceedings, and due diligence investigations in support of product releases, enforcement actions and/or company acquisitions. I have represented clients in litigation and licensing involving patent infringement, trade secret misappropriation, trade dress infringement, and contract disputes. Leveraging my deep experience in such a wide range of issues and technologies, I’m able to help my clients build and manage valuable patent portfolios and avoid the pitfalls of competitive holdings.

I was recently recognized among the IAM’s 300 Global Leaders for 2023-24. I was chosen as one of The World’s Leading IP Strategists 2022-23 for the IAM’s Strategy 300. I was also recommended for patent prosecution in 2023 by the IAM Patent 1000. IAM’s Strategy 300 Global Leaders 2024 is a publication that showcases intellectual property professionals who innovate, inspire, and go above and beyond to deliver value for clients Read More here

In addition, Martindale-Hubbell has identified me as an AV Preeminent Attorney every year since 2013. Read more.


Mark C. Zimmerman, JD, MSEE, BSEE

As a founding member of Hanley, Flight & Zimmerman, I have experience in U.S. and foreign patent prosecution and client counseling with particular emphasis in the electrical and mechanical fields. In addition to patent prosecution, my experience includes directing post-grant proceedings in the USPTO and acquisition negotiations. Additionally, I’ve rendered numerous non-infringement and invalidity opinions as well as testified at trial.

I’ve worked with technologies including, among other things, mobile telephones, networks, semiconductors, remotely-readable meters, industrial equipment, spray nozzles, kitchen fixtures, and firearms.

Before starting a legal career, I worked as a design engineer at Motorola Cordless Products, specializing in RF and audio circuit design. I earned my JD from DePaul University College of Law, with honors. I also earned an MS in Electrical Engineering and Computer Science from University of Illinois, Chicago, and my BS in Electrical Engineering, magna cum laude, from Marquette University.

In 2023, I was Recommended for Patent Prosecution by the IAM Patent 1000 and was designated a Patent Star in the United States (national) and Illinois from Managing IP’s IP Stars, an annual guide to the top intellectual property attorneys in Illinois and nationwide. IP Stars Read Here

Michael W. Zimmerman, JD, MSEE, BSEE

The most enjoyable aspect of my work is having the opportunity to work with inventors to facilitate the development of their ideas into patentable inventions. My engineering background allows me to speak the inventors’ language and to recognize where further development of an application is needed.

As a member of Hanley, Flight & Zimmerman, I have prepared and prosecuted U.S. and foreign patent applications in the areas of software systems, digital media systems, cellular timing circuitry, and low-level computer operations software. I’ve also conducted patent litigation assistance for both defensive and offensive investigations and patent assertions, and I’ve prepared and assisted with the preparation of non-infringement and validity opinions.

Prior to attending law school, I performed validation procedures on software and embedded medical-monitoring devices at GE Medical Systems, Inc. I also developed hardware and software tools for automated testing of monitoring devices. I also worked for an internet service provider, managing network equipment and providing customer support.

I earned my JD from Chicago Kent College of Law. I also earned my MS and BS, magna cum laude, in Electrical and Computer Engineering from Marquette University. My thesis was on signal processing, machine learning, and artificial intelligence algorithms for processing cardiac signals to detect cardiac malfunction. My work was published and presented at the 2003 Computers in Cardiology Conference in Thessaloniki, Greece.

Christopher N. George, JD, MSECE, BSCompE

I believe our clients are best served by offering a comprehensive, strategic solution to their intellectual property and business needs. At HFZ, we’ve built a team to provide our clients a wide variety of non-litigation, intellectual property services, which they can leverage to develop and grow their businesses.

I have extensive experience in a wide range of legal arenas including patent drafting and prosecution, patent portfolio development and management, brainstorming and IP capture, patent landscaping, patent reexamination, litigation, licensing, and due diligence and opinion analysis. I also serve as seconded in-house counsel for a Fortune 5 client to advise them on patent strategy matters.

My experience in technology spans a wide variety of consumer products and manufacturing systems as well as imaging systems, image processing, analog and digital audio, casino gaming systems, telecommunications and data networks, distributed computer systems, electronic storage devices, financial trading systems, anti-virus and security software, and signal processing applications.

Prior to practicing law, I worked in the field of computer architecture and am an inventor on a patent related to runtime software optimization.

Felipe Hernandez, JD, BSEE

I work with various large and small corporate clients in a diverse range of technology areas including software, electrical, and mechanical technologies. I believe there is no single, rigid approach to serving all clients, neither from a technical standpoint nor from a business perspective. The best IP legal services are customized to meet the needs of each client.

I spent several years as an electrical engineer before joining Hanley, Flight & Zimmerman in 2003. I developed electrical hardware architectures for multimedia platforms of next-generation mobile phones at Motorola, Inc. In that capacity, I worked with several different microprocessor families, digital multimedia codecs, LCD controllers, compression algorithms, and communication protocols. At Palm, Inc. I developed electrical hardware architectures for Palm’s line of premium handheld PDA devices, and I wrote firmware and software for mobile computing.

My current practice involves preparing and prosecuting domestic, international, and foreign patent applications. I also counsel clients on non-infringement and invalidity positions as well as other patent related matters.

Joseph T. Jasper, JD, BSBME

We strive to know each client’s business. Leveraging that knowledge, we facilitate clients’ ability to use their intellectual property to expand operations with confidence. With a focus on the medical, electrical and mechanical arts, my practice provides non-infringement and invalidity opinions to clear products or assure clients freedom to operate.

Working with engineers and in-house counsel, I help our clients generate patent portfolios and expand their businesses by developing and executing prosecution strategies including post-grant proceedings. I also coordinate with overseas counsel in opposition proceedings, procure federal trademark registrations, and manage global trademark portfolios, which includes managing and litigating trademark opposition and cancellation proceedings. Additionally, I draft and negotiate licensing agreements, provide counseling related to copyright issues and procure federal copyright registrations.

William E. Jacklin, JD, Ph.D. EE, MSEE, BSEE

Prior to joining HFZ, I was the engineering manager for DSP development at PrairieComm, Inc., where I designed and managed the development of physical layer technology for WCDMA (UMTS) and GSM/GPRS/EDGE mobile cellular systems. I also worked at Northrop Grumman Corp., where I designed and implemented DSP algorithms and communication protocols for wireless systems. I am a named inventor on six granted U.S. patents.

At HFZ, I specialize in both electrical and mechanical arts. My real-world engineering experience allows me to thoroughly understand the scope and breadth of our clients’ inventions and technology portfolios, and I strive to provide guidance and pursue patent protection targeted to each client’s specific objectives.

Peter J. Cesarz, JD, BSEE

Prior to entering the field of patent law, I was employed by Agilent Technologies, specializing in test systems design and development for industries involved in electro-optics, medical applications, and aerospace defense. I was also part of General Electric’s Technical Leadership Program (Edison Engineering Program), where I was involved with internal code and standards, electronics products design, and next generation product research and development.

At HFZ, I enjoy the inventive diversity brought by the clients that we serve, which always ensures new and interesting intellectual property challenges to tackle. I often find that my prior experience as an engineer and consultant bolsters my ability to comprehend new inventive subject matter and efficiently communicate with inventors.

Marianne Buckley , JD, BSBME

Before practicing law, I worked in the research and development department of a healthcare data analytics company. In this role, I saw firsthand how innovation can drive a company’s success. During law school, I interned with the Office of General Counsel at the American Medical Association, where I came to recognize the unique role of in-house counsel in protecting the interests of a business. In my patent prosecution practice, I draw upon these experiences to work with our clients in obtaining intellectual property protection that advances their business goals.

At HFZ, I prepare and prosecute U.S. and foreign patent applications in the mechanical and electro-mechanical arts. I have experience pursuing our clients’ patent rights in a variety of technologies, including medical devices, neuromarketing tools, child care products, information systems, and process control devices. I also assist in counseling our clients with regards to patentability, validity, and infringement matters. Additionally, I help clients obtain trademark protection and manage their trademark portfolios.