A provisional patent is a low-cost mechanism to secure a filing date for a later non-provisional patent. Since the United States is a first-to-file jurisdiction, it is critical to secure the earliest filing date possible for your patent. Under U.S. patent law, a subsequently-filed non-provisional patent can claim the filing date of the provisional patent as long as the provisional patent is sufficiently detailed to support the claims of in the non-provisional patent disclosure. Provisional patents are not examined and serve only to preserve the filing date.