If your provisional patent application has expired after 1 year and you have not yet filed a full non-provisional patent application, you may be able to file the full non-provisional patent application late, or file a new provisional patent application.
1) File the non-provisional patent application late
If it has been less than 2 months since your provisional patent application expired, it may be possible to ask the US Patent Office to allow you to file the non-provisional patent application late and still inherit the date saved by your provisional patent application. For example, let’s say you filed a provisional patent application October 4, 2017 and the provisional patent application expired October 4, 2018 but you didn’t file a non-provisional patent application on time. You could still file a non-provisional patent application by December 4, 2018, 2 months late, and ask the Patent Office to allow you to still use the October 4, 2017 date saved by your provisional patent application. As long as you missed the due date unintentionally, such as by accident, the Patent Office should allow you to still use the date of the provisional patent application. However, hurry, you can only be late up to 2 months. Further, you have to make a special request to the Patent Office. Have a patent attorney or agent handle this delicate matter for you promptly.
2) File a new provisional patent application
Since the old provisional patent application expired, it’s lost and gone. But you can file a new provisional patent application and get a new date. There are risks with this though. You are now later in line with the patent office. For example, let’s say you used to have a provisional patent application with a date of October 4, 2017. After October 4, 2108, it expired and you didn’t file a non-provisional patent application. If you file a new provisional patent application say October 5, 2018, your date now is October 5, 2018. Your old 2017 date is still lost. It doesn’t matter that you filed a new provisional patent application, your old one is still hone. Someone who has a patent application date that used to be after your date, could now be in front of your date since you lost your 2017 date and got a new 2018 date. This is the risk of letting your provisional patent application expire without timely filing a full non-provisional patent application. See this explained in more detail with timeline visuals in the article Understanding Provisional Patent Applications.
Also keep in mind that if it’s been more than 1 year since you showed your invention to the public, a new provisional patent application may be useless for you. Patent law says you need to have a patent application date that is no more than 1 year from when you showed your invention to the public. So if you put your invention on YouTube more than a year ago, for example, filing a new provisional patent application will be useless as you are no longer eligible for a patent. Discuss with us if you are in such a unique scenario.