A perennial challenge in patenting is to both cover your product and block design-arounds. It is understandably frustrating to incur the expense and disclosure requirements of the patent process only to find that a competitor is fielding a product just outside the scope of your claims. The competitor may have even carefully studied and actively designed around the claims. To a certain extent design-arounds can be foreclosed at the drafting stage, but not every design-around is foreseeable. One way to deal with this problem is by keeping the patent family open. In other words, keep at least one continuing application pending. As long as the family is open, new members can be added. Therefore, this practice may allow you to file a new application with claims that read directly on the competitor’s product. Provided that the claims of the new child application are entitled to the parent’s filing date, the attempted design-around becomes infringement. In effect an open family creates flexibility for the patent owner, and risk for the competitor.
Open patent families are a tactically powerful portfolio management tool, but they do have limitations. One limitation is that new matter added in a continuing application will not necessarily be entitled to the parent’s filing date. For that reason, it is good practice to file continuing applications for incremental improvements as they are created, rather than wait and see what your competitors devise. One of these incremental improvements may turn out to be your competitor’s would-be design-around.
Another limitation is that once a family closes, it is between difficult and impossible to reopen it. The procedure used to reopen prosecution is known as Reissue, and it is meant for correcting errors in a granted patent that make it partly or wholly inoperative or invalid. In the absence of such an error, there would be no grounds for reopening prosecution at the time you need to file a continuing application; therefore, the better choice is clearly to keep the family open in the first place.
Mr. Frisina is a partner in the intellectual property practice at Buckingham Doolittle & Burroughs LLC. Attorney Frisina is a specialist in patent and trademark law, having prosecuted hundreds of chemical, electrical, and software cases. His practice encompasses preparation and prosecution, licensing, and litigation matters.
