CNBC Disruptor 50

The nick in Gillette suit against upstart Dollar Shave Club

How Dollar Shave Club took on the industry

Gillette's attempt to slow the advances of upstart Dollar Shave Club with a patent lawsuit could end in failure, according to a financial firm that analyzes patents and other intellectual property.

On Thursday, Gillette, the 120-year-old shaving company owned by Procter & Gamble, sued Dollar Shave Club for alleged infringement of patent US6684513 (also known by the shortened '513 patent label). The patent describes a razor blade with a specific type of coating, which, according to the Gillette complaint, "provides the razor blade with excellent shaving characteristics … and promotes durability."

But the biggest nick in Gillette's legal argument may be its own patent.

David Pratt, president of Charlottesville, Virginia-based MCAM International, said the Gillette patent is "highly subject to invalidation if proper information is brought to light."

Specifically, MCAM found 13 existing patents with a high level of overlap to the one Gillette is using as the basis for the suit against Dollar Shave Club. "Amazingly, at least seven are patents owned by Gillette," Pratt said.

Ouch! Gillette suing Dollar Shave Club for patent infringement

Patent filers have a responsibility to cite "prior art," or previous patents for science or technology most closely related to what the new patent is meant to protect. Gillette's '513 cites more than 25 other patents as prior art, but its failure to mention others could give a judge cause to invalidate the patent.

In response to Pratt's argument, a Gillette spokesman said that the company would not have brought the lawsuit unless it believed the patent was valid. The spokesman added that it's common for independent experts to testify in court, but patent issues are ultimately for the court to decide, and Gillette is confident in its case.

Deborah Majoras, P&G chief legal officer, said in a release, "Our patents help protect the many technical advancements we've made through the years — and when it becomes necessary, we take action to protect these important assets."

Pratt said Dollar Shave might be able to countersue to invalidate Gillette's '513 patent.

Citing advice from legal counsel, Dollar Shave declined to comment.

Pratt said other patents for coated razor blades date back to at least 1975. Patent US3916523, originally owned by Warner Lambert (now part of Pfizer), was cited by Gillette at least twice as prior art for new patents — once in 1994 and again in 2010 — but not for '513, which was granted in 2004.

Dollar Shave Club began selling razors online in 2012 and has grown quickly. Today it has a reported 8 percent share of the $3 billion global shaving market.

Dollar Shave Club was No. 45 on the 2015 CNBC Disruptor 50 list.