The following case illustrates the difficulty in being able to predict the outcome of patent litigation.  It also provides hints at improving ones patent drafting technique.  During patent litigation, the claim terms are construed in light of (1) the plain meaning of the terms, (2) the specification and (3) the prosecution history among other things. [...]

Written Description Requirement To get a patent, an inventor must satisfy the written description requirement.  This is accomplished through the preparation of a patent application which describes the invention and shows any drawings if necessary for the understanding of the invention.  To satisfy the written description requirement, the discussion of the invention must correspond to the claims. [...]

Once a patent application is filed, it receives a priority date for all that it discloses and nothing more. The inventor can claim anything within the disclosure as being a part his or her invention. If the inventor wants to claim an invention that varies from the disclosure, then the claim language must be generalized so as to encompass the variation but cannot be shifted unless the original disclosure provides “written description” of the claimed variation. Otherwise, the claim will be invalid for lack of “written description” in the specification.

Some inventors attempt to draft their own patent application.  However, in my opinion, doing so is not advised.  The reason is that many different legal principles must be applied when drafting the patent application.  A self help book may be able to discuss these principles but inventors may not be able to assimilate these principles [...]