WD-40 Co. didn't infringe an Illinois man's "The Inhibitor" trademarks with its Specialist Long-Term Corrosion Inhibitor anti-rust product, a federal district court ruled Sept. 9.

The U.S. District Court for the Northern District of Illinois granted summary judgment and ruled that WD-40's use of the word "inhibitor" was fair use, and that its crosshair mark was not sufficiently similar to Jeffrey Sorensen's own mark to create a likelihood of confusion.

Sorensen had presented some evidence that WD-40 was aware of the existence of "The Inhibitor," originally manufactured by his former company, Van Patten Indus. of Rockford, Ill. However, the court ruled that this wasn't sufficient to support a claim that WD-40 used his mark in bad faith.

The Inhibitors. 

Sorensen applies his three "inhibitor" marks to a series of volatile corrosion inhibitor (VCI) (in layman's terms, rust prevention) products that he specifically advertises toward hunters and fishermen. 


The three marks are the words "The Inhibitor," an orange crosshair, and the design mark of the word "inhibitor" in all caps with the crosshair in place of the letter "o." The "The Inhibitor" word mark was registered in 2002, but the other two marks have not been registered.

The orange crosshair:


The design of the word "inhibitor" in all caps with the crosshair in place of the letter "o":


WD-40, meanwhile, has been well-known for its lubricants for over 50 years. In 2011, the company released a line of "Specialist" products, all of which include a crosshair mark on their containers.

wd40_specialist (resized)

WD-40 registered this crosshair design mark in 2012.

The "Specialist" line includes a Long Term Corrosion Inhibitor, which, like Sorensen's "Inhibitor," contains VCI and is used to prevent rusting. 

The products might seem facially similar, although unlike Sorensen, WD-40 doesn't market its product to sportsmen specifically. Noting these similarities, Sorensen sued WD-40 for trademark infringement in Illinois. Interestingly, discovery revealed that consultants on the creation of WD-40's Specialist line had also suggested a partnership with Van Patten in their conception of the WD-40 inhibitor product.

The court found, however, that the evidence just wasn't enough to support Sorensen's infringement claims.

Fair Use.

First, the court found that even if WD-40 did know of Sorensen's "The Inhibitor" word mark before naming its product, WD-40 had availed itself of the fair use affirmative defense in using the word "inhibitor." Under the Lanham Act, trademark fair use applies when a mark is used in a non-trademark way, descriptively, fairly and in good faith. 

Here, the court found that WD-40 used "inhibitor" in a non-trademark way because it did not use the word to identify Sorensen or his company as the source of the product. This was supported in part by evidence of WD-40's use of its famous shield logo on the container, and of other competitors' use of the word "inhibitor" in their products.

The court also found that the word "inhibitor" was descriptive, under the word's dictionary definition as "an agent that slows or interferes with a chemical action."

Finally, the court determined that even assuming WD-40 knew of Sorensen's "inhibitor" word mark before naming its product, that knowledge alone is not enough to prove that WD-40 used the mark in bad faith – going on to say that if it was sufficient proof of bad faith, fair use would never be viable since the defense requires actual use of the competing trademark.

No Likelihood of Confusion.

The court also determined that there was no likelihood of confusion between the products under Seventh Circuit precedent. This was supported by facts that included the differences in the crosshairs themselves, the distinctiveness of WD-40's use of the crosshair in conjunction with its shield mark, the lack of actual evidence of confusion or side-by-side sales, the weakness of Sorensen's marks, and the absence of proof that WD-40 intended to pass off its product as Sorensen's product. 

The court also dismissed Sorensen's state law claims because they required a possibility of likelihood of confusion to move forward.

Full text of the opinion here.