Columbia Insurance Co. v. Simpson Strong-Tie Company Inc

Background

Columbia Insurance Co. owns U.S. Patent No. 10,316,510, and MiTek Inc. is its exclusive licensee. The patent covers a hanger designed to connect structural components such as trusses or joists to a wall while allowing two layers of 5/8-inch fire-resistant sheathing to fit between parts of the hanger. The design seeks to avoid the large cutouts in sheathing required by traditional hangers.

The plaintiffs claimed that Simpson Strong-Tie Company Inc.’s DGF, DGHF, and DGBF Fire Wall Hangers infringed claims of the patent. They asked the court for a preliminary injunction, which is an order issued before final judgment to temporarily stop the challenged conduct.

Legal standard

To obtain a preliminary injunction, the plaintiffs had to show a likelihood of success on the merits, irreparable harm without an injunction, a favorable balance of hardships, and a favorable public-interest effect. The court stated that the plaintiffs could not receive an injunction unless they established both a likelihood of success and irreparable harm.

At this stage, Simpson needed only to raise a substantial question about patent invalidity—meaning a serious enough question that the patent may not be legally valid. The burden was lower than the proof required to establish invalidity at trial.

Analysis

Simpson challenged the patent on anticipation and obviousness grounds. Anticipation means that one earlier reference discloses every limitation of the claimed invention. The court found that Simpson had not identified a single prior-art reference disclosing every limitation, so Simpson had not presented an anticipation defense with substantial merit.

The court reached a different conclusion about obviousness. Simpson relied on combinations involving Tsukamoto, Gilb ’155, Gilb ’792, Timony, and Bundy. The court determined that Bundy disclosed, in its preferred embodiment, two layers of 5/8-inch drywall and that the other references supplied many of the remaining hanger features. The court also found that a person of ordinary skill in the field would have been motivated to combine the references and would have had a reasonable expectation of success in achieving the claimed spacing.

The court rejected the plaintiffs’ arguments that the prior-art references were from different types of wall construction or that modifying Gilb ’155 would undermine its purpose. It also found that the plaintiffs’ evidence of an unmet need and other secondary considerations did not significantly weigh against obviousness.

Ruling

The court found that Simpson had raised a substantial question about whether the patent was obvious. As a result, the plaintiffs could not show a likelihood of success on the merits. The court therefore denied the plaintiffs’ motion for a preliminary injunction. The opinion did not state that the patent was finally invalid or that the infringement claims were finally resolved.