Updating provisional patent application
One reason I like to suggest starting with a provisional patent application as a way to initiate the patent process is because they are cheaper to prepare (because there are no formal requirements) and the filing fee due to the United States Patent Office at the time of filing is only 0 for small entities (i.e., individuals, universities and companies with 500 or fewer employees), which saves you several hundreds of dollars compared to the filing fees for a non-provisional patent application.
Similarly, the first rule of drafting a patent application is that you need the help of a patent professional, which means a patent attorney or a patent agent.
Self-drafting patent applications is not for everyone and should be thoroughly investigated before doing so.
Valuable patent rights can be lost attempting to self-draft a patent application.
This provided a lower-cost first patent filing in the United States and gave United States based applicants parity with other applicants under the GATT Uruguay Round Agreements. (Note: You can also file for a provisional patent if you are a foreign applicant - but that would not increase protection beyond twenty-one years.)A provisional patent application allows filing without any formal patent claims, oath or declaration, or any information disclosure ( prior art) statement (1).
It provides the means to establish an early effective filing date in a non-provisional patent application (2).