Patent application drafting is complex, but the law allows incomplete applications to be filed in both Canada and the United States. These incomplete applications are called provisionals. Are they a useful short cut to a patent application filing?
The basic problem is that if no attempt is made to generalize claims and provide proper support for them, a non-provisional filed claiming priority from a provisional may protect only the precise embodiment disclosed in the provisional and therefore may be useless.
One simple way of putting it is: there are no short cuts.
A proper description in a patent application, whether provisional or non-provisional, must disclose an invention in such a way that a person skilled in the art can make and use the invention, without undue experimentation, and must disclose the best known way of carrying out the invention.
This requirement is relatively easily met. A provisional patent disclosure usually describes something in an adequate manner. Providing an inventor can honestly state that a provisional patent disclosure properly discloses the invention that the inventor has made, the minimum requirements for filing a provisional patent application are met. This is the least cost approach to filing a provisional.
In a patent, the claims define the invention. However, a provisional need not have claims. A problem arises that we cannot determine what the invention is and therefore whether it is properly disclosed without drafting claims.
Consider an example. A provisional filed by inventor X discloses an invention comprising a first embodiment A (triangles) and a second embodiment B (rectangles). After filing of the provisional by X, inventor Y files a provisional application disclosing pentagons, which, it turns out, is the preferred manner of operating the invention. When the inventor X comes to file a non-provisional application, is the inventor X entitled to claim polygons? I call this the generalization problem.
The generalization problem is of potentially far reaching consequence. If X is entitled to claim polygons, X can stop inventor Y and inventor Y's assignees from profiting from pentagons. Whether inventor X can claim polygons depends on whether it can be reasonably inferred that inventor X had disclosed polygons in the provisional application filed by X. Although in some cases, the circumstances of the case might make it possible for an inventor to generalize from examples (ie, polygons from two examples of polygons), the likelihood is that inventor X will not be able to claim polygons before the patent offices.
Furthermore, and this may be more critical, the inventor’s own publication of the technology after the filing of the provisional but before filing the application in a country that has an absolute novelty test (such as Europe) may be fatal to generalized claims in that country. In the example given above, the client’s own post-provisional publication of triangles and squares might invalidate a later generalized claim to polygons, even though the provisional provides priority for triangles and squares.
Furthermore, the inventor’s own publication of the technology prior to filing a provisional in the US may be fatal to generalized claims in a US non-provisional application filed more than one year after the original publication if the provisional disclosure does not contain support for the generalized claims.
A claim is a combination of elements or steps. The generalization problem can apply to any of the elements or steps or any combination of the elements or steps. Hence, without some serious thinking about the scope of an invention, which means effectively without drafting claims, it is not possible to define the scope of the invention. If no generalization occurs, all that the provisional may protect is the specific example in the inventor's disclosure, and therefore might be easily designed around.