An individual who wants the benefit of marking an invention or product as “Patent Pending” must make a good faith effort to ensure that the articles are properly and consistently marked.
Marking an invention or product as "Patent Pending" alerts the public that your invention or product may soon be patent protected and that once the patent issues, you have the right to initiate a patent infringement lawsuit infringers.
An individual or business may mark the invention or product with “Patent Pending” once a patent application has been filed with the Patent Office.
*Note that it is a criminal offense to mark or offer to sell an article as “Patent Pending,” when an application for the invention has not yet been filed.
In deciding how to mark an invention or product as “Patent Pending”, an individual should be mindful of the purpose of the mark and use common sense. For example, patent markings may be etched, molded, or printed onto the invention or product or if you are unable directly mark the invention or product itself due to “the character of the article”, the mark may be placed on the packaging of the invention or product. The packaging may include a box enclosing the invention or product or marketing and promotional materials. In the event that label or marks are not seen or fall off of the invention or product, the courts follow the “rule of reason” approach, where constructive notice is given when the patent applicant consistently marks substantially all of the articles.
Once a patent has been issued, you become a patentee rather than a patent applicant.
The law also allows patented invention or product to be marked “virtually” by using the internet. In order to comply with the virtual marking requirements, the individual or company must mark the invention or product itself (or the invention or product packaging if it is not possible to mark the invention or product) with the word “patent” or “pat.” along with a freely-accessible internet address where anyone can find the patent numbers associated with the patented invention or product. An advantage of virtual markings may be the aesthetic appeal. Additionally, virtual markings may offer increased ease of updating and identifying later issued patents relating to the invention or product without having to remark the invention or product individually because the revisions may only need to be made to the website page.