“Gravity Defyer has informed the FTC of the obvious logical flaws in its position – and that its position violates Gravity Defyer’s First Amendment right to broadcast and consumers’ right to receive truthful and not misleading scientific information. The FTC was relentless in its bizarre stance,” the company said.

In April, Gravity Defyer filed its own lawsuit against the FTC. Much of it is based on a small 2017 study that the company has long used to back up its pain relief claims. The study, published recently Journal of the American Podiatric Associationfound that Gravity Defyer’s “shock-absorbing insole” reduced knee pain by an average of 85%, much better than traditional insoles.

The FTC says the study has “substantial flaws” because of its small size (52 participants) and duration (5 weeks), and because it relied on participants’ self-reported pain levels.

“It was also designed only to measure knee pain. Thus, the study was not sufficient to determine the effects of wearing the Gravity Defyer shoes on knee, back, ankle or foot pain, or on the pain associated with the specific conditions claimed,” the FTC said.

The Commission, which voted 4-0 to file the lawsuit, is seeking an order permanently barring Gravity Defyer and Elnekaveh from making misleading or deceptive pain relief claims, as well as civil penalties.