In establishing a disclosure, applicant may rely not only on the description and drawing as filed but also on the claims present on the filing date of the application if their content justifies it.
Where subject matter not shown in the drawing or described in the description is claimed in the application as filed, and such claim itself constitutes a clear disclosure of this subject matter, then the claim should be treated on its merits, and requirement made to amend the drawing and description to show this subject matter. The claim should not be objected to or rejected because this subject matter is lacking in the drawing and description. It is the drawing and description that are defective, not the claim.
It is, of course, to be understood that this disclosure in the claim must be sufficiently specific and detailed to support the necessary amendment of the drawing and description.
On the other hand, when the subject matter is not shown in the drawing or described in the description, the words of the original claim must sufficiently describe the invention so that one of ordinary skill in the art would recognize that the inventor had possession of the full scope of the claimed invention. If the claim does not provide its own description in this case, the claim should be rejected under 35 U.S.C. 112(a) as failing to be supported by an adequate written description.