When people think of patents, they often imagine large companies expanding their intellectual property portfolios or competing for technological dominance. However, patents serve another important role—they are a historical record of innovation in America. The U.S. patent system dates back to the founding of the country, with Article 1, Section 8 of the Constitution granting Congress the power “To promote the progress of science and useful arts, by securing for limited times to authors and inventors the exclusive right to their respective writings and discoveries.” Congress passed the first Patent Act in 1790, and since then, the patent system has documented centuries of American ingenuity.

Patents older than 20 years have likely expired, meaning the inventions are now in the public domain. One unexpected way patent archives can be useful is in antiquing and restoration. For example, my mom has a passion for antiquing and frequently comes across furniture, lamps, mechanical gadgets, and other vintage finds. Many of these pieces have patent numbers engraved or embossed on their backs, undersides, or other hidden areas. She takes the opportunity to look up these patents, uncovering valuable historical information about the original inventor, the time period, and even detailed descriptions of how the item was designed to function. This can be incredibly helpful for restoration efforts, as it reveals whether certain components are missing or if modifications have been made over time.

Some well-known vintage inventions with patents include the Singer sewing machines (Patent No. 8,294, issued in 1851), Thomas Edison’s Phonograph (Patent No. 200,521, issued in 1878), and the KitchenAid stand mixer (Patent No. 1,988,244, issued in 1935). It is also important to note that not all patents cover the function of an item; design patents, for example, protect the ornamental appearance of an object. Many antique furniture pieces and decorative items have design patents rather than utility patents, for example a Tiffany lampshade (Patent No. D45,205, issued in 1914) and a Fender guitar (Patent No. D164,227, issued in 1951).

While free resources like the USPTO’s Public Patent Search and Google Patents are great for looking up patent numbers, sometimes the search can get tricky—especially with older patents. The patent numbering as we know it today was not standardized until 1836. Even then, some products were marked with only a patent date instead of its patent number. This practice stemmed from early US patent law, which required manufacturers to physically mark its products with the patent date to serve as legal notice of patent protection. It also allowed patent holders to claim damages starting from the date of marking, rather than from the date when an infringer was notified.

My mom will give me a call when she gets stumped. In cases where a patent number is partially worn away, marked only by the patent date, or when searching for pre-1836 patents, additional tools are needed. We have access to proprietary databases that allow for more advanced searching, including finding patents based on incomplete information.

So, next time you come across a patent number on an antique or vintage item, I encourage you to look it up—you might discover something fascinating about its history. If you hit a roadblock, we are always here to help with in-depth patent searches using specialized tools.