893 Patents Issued For Clients
693 Trademarks Issued or Filed for Clients

It's Patentable

Protect your inventions and intellectual property!

Patent Lawyer in California, Florida, Illinois, New York, Texas, Wisconsin - All 50 States

Patent & Trademark Services

  • Patent writing and filing
  • Patent searching and evaluation
  • Patent infringement opinions
  • Patent litigation
  • Trademark filing
  • Trademark searching
  • Advice for "designing around" patented products
  • Pro se Patent Help
  • Pro se Trademark Help
  • Agent for filing patent application papers
  • Agent for signing trademark papers


US Patent Law Attorney in WI, CA, FL, IL, NY, TX | IP Patent Attorney

Don Ersler is a patent attorney with 28+ years of experience in patent law, plus bachelor degrees in mechanical and electronic engineering, 12 years of design engineering experience, and a juris doctor degree in law. As an experienced patent lawyer, Don has the know-how and skills to write the strongest possible patent application, avoid prior patents, and work around prior art. He will protect your invention or idea.

In addition, Mr. Ersler can provide assistance with intellectual patents as an IP patent attorney. All technologies are applicable to patent law, and Don Ersler can offer the necessary guidance to assure your patents are registered and filed accurately and completely at a reasonable price.

As your patent agent, Don will quote a flat fee for all legal needs related to obtaining your patent, such as Invention Licensing, so you will know all legal costs before you start. Don works with inventors, design departments, and corporate attorneys in the USA and around the world from his office near Milwaukee, Wisconsin.

Previous clients have included inventors needing patents from California, Illinois, New York, Texas, Wisconsin... all corners of the United States and elsewhere. If you need a patent attorney who is not only an experienced lawyer, but also holds college degrees in engineering areas related to most inventions, you will enjoy working with Don Ersler.

Several clients have stated that Don is a patent attorney who understands their invention. 


Carl L. Ricciardi President and General Counsel Altapure, LLC

Until we engaged Don Ersler as patent counsel our experience with several other firms had been, in the main, disappointing. His expertise in the fields of mechanical and electrical engineering coupled with his quick grasp of complicated issues result...

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Matt Collins

Attorney Ersler is by far the best patent attorney we've worked with. His expertise shines through in every thing he's done for us. Why have we placed such an enormous amount of trust in his abilities over the years? Because Attorney Ersler has handl...

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