Patents serve two primary purposes: giving rights to the inventor and preventing others from copying the inventor’s work. That protection is what encourages innovation. However, before you invest time and money in filing a patent, there is a critical step you should not rush through, or worse, skip, and that is the patent search. A comprehensive patent search helps you figure out if your idea is genuinely new or if something similar already exists. Skipping this step could result in wasted development costs, delayed launch, or a rejected application. So, how do you run an effective patent search?

Start With Smart Keyword Searches

From the most basic to the most comprehensive searches, keywords are crucial when conducting a patent search. However, using obvious terms alone may not get you the confidence you need to file a patent. This is because patent documents often use technical or broad language, rather than everyday wording. For example, a coffee cup may be described as a beverage container or a drinking vessel.

As such, a great approach is to list all possible synonyms and build searches around them. You may also consider using Boolean operators like AND, OR, and NOT to narrow or expand the results. Additionally, to prevent your invention from overlapping with international patent filings, include non-English keywords, where possible. This can help avoid missing crucial prior art that may have been captured in other languages, like Chinese or Japanese.

Look Beyond the U.S. Patent Database

While the USPTO database is a good starting point, you should not stop your search there. An examiner could review prior art from anywhere in the world, so it is best to expand your search. Doing this can reduce the risk of overlooking a similar patent filed overseas and also help you assess market realities to inform your decision on how and whether to move forward commercially.

Use Patent Classification Codes

Every patent is assigned classification codes that group inventions by technology area. Identify the proper classification for your invention, as this can help you to quickly locate closely related patents, even if they don’t share obvious keywords.

Search Broader Classifications

One of the most common mistakes people make is searching only for narrow classifications. Patents are sometimes categorized under broader classes, especially when an invention crosses multiple fields. If you limit your search too tightly, you may miss relevant prior art. It’s best to run your patent search in both narrow and broader classifications to ensure you have an idea of the entire landscape and uncover results you might have otherwise missed.

Understand Why You are Searching

It’s essential to understand the goals of your patent search. Are you testing patentability or freedom to operate? If your goal is patentability, you need to determine whether a single document discloses your entire invention or if your idea combines elements that are not disclosed and are likely to be considered inventive. On the other hand, if you are checking freedom to operate, you will need to know whether a relevant patent is still active and if its claims cover your invention. This is where a patent attorney’s guidance becomes especially valuable.

Contact the Business Attorneys at Revision Legal

For more information, contact the experienced Business Lawyers at Revision Legal. You can contact us through the form on this page or call (855) 473-8474.

The Legal Significance of a Thorough Prior Art Search

A patent search has direct legal consequences throughout the lifecycle of your patent. Under 35 U.S.C. §102, an invention is not patentable if it was already patented, described in a printed publication, in public use, on sale, or otherwise available to the public before the effective filing date. A comprehensive prior art search helps you assess patentability before investing in application preparation, identifies the closest prior art so your claims can be strategically drafted to differentiate your invention, and reduces the risk of USPTO rejections that delay prosecution and increase costs.

Under 37 C.F.R. §1.56, applicants and their attorneys have a duty of candor to disclose all known material prior art to the USPTO. Failure to do so—even inadvertently—can render a patent unenforceable on grounds of inequitable conduct. A thorough search before filing is therefore not just strategically valuable; it is part of your legal obligation.

Professional Search vs. DIY: Knowing the Difference

Free tools like Google Patents and the USPTO’s Patent Full-Text and Image Database (PatFT) are useful starting points, but they have limitations. A professional patent search conducted by a registered patent agent or attorney involves structured classification-based searches across multiple databases, including the European Patent Office’s Espacenet and WIPO’s PatentScope. Professional searchers are trained to interpret patent claims, not just titles and abstracts—which is where most layperson searches fall short. A professional search typically runs $1,000 to $3,000—a fraction of the cost of prosecuting a rejected application or defending an infringement case involving prior art that a thorough search would have caught.

Non-Patent Literature: A Critical and Often Overlooked Resource

Prior art is not limited to previously issued patents or published patent applications. Academic papers, conference proceedings, trade publications, product manuals, and publicly available videos can all constitute prior art under 35 U.S.C. §102. USPTO examiners routinely cite non-patent literature (NPL) during prosecution, and a reference that anticipates your claims will result in rejection regardless of whether it is a patent or a journal article. Your search strategy should therefore include relevant technical databases such as IEEE Xplore, PubMed, and Google Scholar, as well as targeted searches for product literature and open-source repositories in your technology area.

Work With a Patent Attorney to Protect Your Invention

A patent search is most valuable when conducted in conjunction with experienced patent counsel who can interpret the results, advise on claim strategy, and guide you through the application process. Revision Legal’s patent attorneys work with inventors and businesses on patentability opinions, USPTO applications, freedom-to-operate analyses, and patent litigation. Contact us to schedule a consultation, or visit our patent law practice page to learn more.

International Patent Protection and the PCT Process

If your business operates or plans to expand internationally, a domestic patent search is only the beginning. Patent rights are territorial—a U.S. patent provides no protection in other countries, and a patent search limited to the USPTO database may miss relevant prior art from other jurisdictions. The Patent Cooperation Treaty (PCT) process, administered by WIPO, allows inventors to file a single international application that preserves the right to pursue patent protection in over 150 member countries, while conducting a preliminary international search and examination that provides useful feedback on patentability before you commit to the cost of national phase entries in individual countries.

The cost of pursuing international patent protection can be substantial—national phase entry fees, translation costs, and local patent attorney fees add up quickly. Strategic prioritization is essential. Work with a patent attorney to identify the markets where your invention is most likely to be commercially valuable and where infringement risk is highest, and concentrate your international filing resources accordingly. For many technology businesses, at a minimum the EU, China, Japan, South Korea, and Canada warrant serious consideration. Starting that analysis with a thorough international prior art search—including the Derwent Innovation database and WIPO PatentScope—lays the foundation for a cost-effective international IP strategy.