A non-provisional utility patent application, filed under 35 U.S.C. § 111(a) on or after December 18, 2013, must include a specification, with or without claims, to receive a filing date (MPEP 601.01(a)). Filing an application that includes a specification without claims is not advisable because the claims are what defines the scope of protection sought for a particular invention. Accordingly, where possible the claims are filed in the application as a part of best practices.
The filing requirements to obtain a filing date are different than the filing requirements to proceed with an examination of the application. If necessary, an application may be filed, with or without claims, to preserve a chain of priority in a series of applications. However, if this occurs, additional components must be filed for examination of the application.

Regardless of whether an application was filed with or without claims, additional components are required to complete the application. These components include a filing fee, a search fee, an examination fee, and an inventor’s oath or declaration. If the applicant is represented by a registered patent attorney or agent, a power of attorney must be filed with the patent office as well. Finally, any drawings necessary to complete the application must also be filed. Together, the application with or without claims, drawings, fees, and an oath or declaration complete the filing requirements for the non-provisional utility patent application.

If all necessary components are not filed at the time of filing the application, a Notice to File Missing Parts of an Application will be issued to the applicant from the patent office. This notice serves the function of informing the applicant that additional elements are still needed in order to complete the application. The notice provides for a shortened 2-month period for responding, with extensions of time of up to 5 months under 37 C.F.R. § 1.136(a), and additional time when appropriate under 37 C.F.R. 1.136(b).

Accordingly, if an applicant is delayed completing the necessary paperwork to complete the full set of filing requirements for examination, and a specification is available, the applicant may file the specification to ensure a chain of priority is maintained and file the other components at a later date. Practically speaking, the specification must be complete and accurate to ensure it meets the disclosure requirements. This is to ensure that the specification is enabling and the invention claimed is adequately described in the specification.