Drafting Useful Dependent Claims

Newer patent attorneys tend to draft dependent claims that are technically correct, but that have no real benefit to the patentee. One common problem is trying to list all viable choices in a given dependent claim. For example, if a parent claim recites a mechanical connector, it does little good for the dependent claim to recite that the connector is selected from the list consisting of a nail, a screw, a bolt, a dowel, a tack, a brad, a clamp…" and so forth. If it turns out that the parent claim is invalid because of prior art relating to the connector being a tack, then both the parent claim and the child claim will be invalidated. If the attorney had listed screws, bolts, and dowels in one dependent claim, and nails, tacks, and brads in another dependent claim, it is entirely possible that the first of those dependent claims would still be left standing.

Newer patent attorneys also tend to draft dependent claims that are irrelevant. Remember, the main purpose of most patents is to keep competitors out of the marketplace, or to at least make their entry into the marketplace much more difficult. An extreme example of a worthless dependent claim is one directed to an ornamental aspect of a useful device. If the inventor developed a ballpoint pen having a new type of ink, the invention is in the ink, not in the color of the barrel of the pen. The selection of blue, black, or white barrel is merely a design choice having nothing to do with the inventive features. Dependent claims to the color of the barrel would do little more than emphasize that the patent attorney needs to improve his skills at writing patent applications.