Rule 11 of the Federal Rules of Civil Procedure requires an attorney to conduct a reasonable inquiry into the laws and facts before filing a pleading in a court and to certify that the claims contained in the pleading are not frivolous, legally unreasonable, without factual foundation or asserted for improper purposes. This inquiry must be undertaken before the suit is filed, not after. The question is, “What is a reasonable inquiry into the facts and law in a patent case?”

The scope of a patent’s legal protection is defined by the claims. Therefore, a pre-filing investigation in a patent case should focus on the scope and content of the claims as applied to the accused product. A good first step is to interpret the claims of the patent as their exact language will, in all likelihood, become a key issue in the litigation. Accordingly, it is appropriate for counsel to undertake an analysis of patent claim scope prior to filing.

One approach to claim interpretation is to prepare a claim chart. Such a chart will break down the claim language into individual terms or limitations that may be important in construing the patent. The claim chart may then identify the meaning of each claim term based on factors such as dictionary definitions and the content of the patent specification. Courts have sometimes held that preparation of a claim chart is not required to satisfy the requirements of Rule 11, as long as counsel reviewed the claims, the written description, and the prosecution history and interpreted individual claim terms prior to filing the complaint.

Failure to conduct an analysis of the claim language is not generally acceptable. In one case, an attorney was found to have violated Rule 11 when the extent of his claim analysis appeared to be examining one of the asserted patent claims and indicating that he “saw no problem with it.” At the same time, courts have recognized that there may be differences in claim interpretation and have not necessarily required a party to have used the ultimately preferred interpretation for purposes of satisfying Rule 11.

The next key step is to identify the accused product. Preparing a claim chart without applying the construed claims to a product is not sufficient. In one case, there was an allegation of infringement based on some Internet functionality rather than an identifiable product. The court held that this was not sufficient. The court stated, “Determining infringement requires claim interpretation, and that claims read on the accused device. It is implicit that identification of the accused device is a necessary prerequisite to determining infringement.” Clearly, this is a basic step in an adequate pre-filing investigation.

It is therefore necessary to apply the claim language to the accused product. This may well involve performing an analysis on the product to determine whether it contains each of the elements of the claim. Courts have looked at what is reasonable under the circumstances in obtaining and analyzing the accused product. In a case where the item was an inexpensive software application, the court found a violation of Rule 11 by not acquiring the application and determining how it operated. At the same time, a plaintiff was not required to acquire and analyze a massive roller coaster brake, but rather was able to rely on publically available documents, a visual inspection, and a review by experts. Similarly, a plaintiff was not required to perform a complete chemical analysis on an accused composition where the content of the composition was discernable from advertising and product information. This information indicated that the composition fell within the scope of the construed claim language.

Another area of importance is patent validity. Patents are presumed valid. It is, however, good practice to conduct an analysis of patent validity prior to bringing a patent infringement action. Such an analysis may include additional patent searching, review of the prosecution history, and review of other relevant facts.

Finally, counsel should undertake an adequate investigation of other legal bases of the patent infringement claim, including confirming that the plaintiff has ownership of the patent rights asserted. If there is an issue with ownership it should be addressed by an assignment or other steps prior to initiation of the litigation.

Pre-filing investigation has the potential to set the tone for the forthcoming litigation. If the claims are carefully construed, the accused product identified and analyzed, and the claims applied to the accused product, the plaintiff has an accurate road map for the litigation ahead. If any of these steps are missing or inadequate, the plaintiff can expects problems to arise rapidly.