PTRC | Researching Trends in Patent Databases

Patent or Copyright?

  • If you're interested in software development trends, the whole picture will not be reflected in patent databases. Software often qualifies as a creative work and so is protected by copyright instead of patents.
  • Search post-1978 copyright registrations at
  • Pre-1978 registrations are only searchable at the Copyright Office in Washington, DC.

Who are the major players?

  • Identify individuals or companies that are doing research in the area in which you're interested. Consider whether there is a particular geographic area associated with the industry (think Silicon Valley for IT, for instance). Combine searches for these with a range of dates to narrow your results.
Entity Search As
  • Inventor
  • Assignee
  • Assignee
Geographical area
  • Inventor City
  • Inventor State
  • Inventor Country
  • Assignee City
  • Assignee State
  • Assignee Country
  • Keep in mind that an individual's name may be listed in many different ways. Gene Brown might also be noted as Eugene Brown, E. Brown, E. R. Brown, Eugene R. Brown.
  • Also if you're tracing older trends, remember spelling wasn't standardized. Don't assume you have the correct spelling: search alternate spellings of both first and last names. Examples for this last name: Brown, Browne, Braun, etc.

Notice the Details

  • As you peruse results from your initial searches, take note of whether a particular examiner is listed frequently for a given technical area. Examiners tend to specialize so can be useful markers of a particular technology or field.
  • Both Primary and Assistant Examiner names can be searched.

Follow Related Research

  • Use the "References Cited" and "Referenced By" sections of a patent to locate related technologies.
  • References Cited are older patents that are similar enough to the one under consideration for the applicant to have made note of them.
  • Referenced By are newer patents, issued after the one under consideration, which cite it.

Non-Patent Literature

Other kinds of databases offer invaluable information for trend research. Consider these sources and think what other similar databases may be appropriate for your topic area. (Note: The databases linked here are limited to NCSU users only.)

  • General / News Databases
  • Subject Specific Databases
  • Conference Proceedings: these will show up within the subject specific databases or by searching our online catalog.
    TIP: Conference proceedings can be tricky to find. Try searching for the name of the conference, the city where a conference was held, and the name of the organization sponsoring the conference. Rarely will a set of proceedings show up by searching the title of a presentation but it's worth trying in case the proceedings happens to have the presentation titles in a table of contents.
  • Internet: For more recent technologies there may be blogs or web sites that are particularly concerned with a given technology. These are likely to be much more difficult to use in tracing developments unless they are very focused and have been in place for a while, but may still be worth considering in your research.