Chiropractor to the Stars Sues Therabody for Allegedly Stealing His Designs

2:50 PM PT -- Jonathan Feldman, General Counsel at Therabody, tells TMZ ... “We believe the claims in the lawsuit are without merit. Therabody has a proud history of innovation and collaboration, and we take intellectual property rights very seriously. We intend to vigorously defend ourselves against these allegations and look forward to sharing the facts through the appropriate legal process.”

Celebrity-approved chiropractor and MoveU founder Dr. Mike Wasilisin is cracking more than backs ... 'cause he's taking legal action against Therabody for allegedly stealing his designs.

This is what we know ... in the Tuesday complaint obtained by TMZ, Dr. Mike -- whose clients include Antonio Brown, top comedians, talk show hosts, athletes and Bollywood stars -- says he shook hands with Therabody founder Dr. Jason Wersland years ago ... just to have that deal thrown out.

According to the doc, Dr. Mike says he and Dr. Jason hammered out a deal all the way back in 2017, which would allow Therabody to use his two massage tip designs in exchange for compensation and being listed as an inventor on the patents.

Dr. Mike says he became aware the two patents excluded his name in 2023. To rub more dirt into the wound ... Dr. Mike says this was 2 years after Dr. Jason personally assured him he would never steal his ideas.

Well ... you can see for yourself. The designs Dr. Mike says are his are strikingly similar to Therabody's massage tips.

The Thumb Attachment and Wedge Attachment were allegedly patented in late 2017 ... which only names Jason, and two other people -- no Mike.

Now, Dr. Mike wants his money and design credit.

He is asking for undisclosed compensatory, consequential and punitive damage ... and he demands his name -- and only his -- appear on the patent.

He says his biggest regret is taking Dr. Jason's word, explaining ... "What makes this so disappointing is that I trusted Dr. Wersland, personally and professionally. Now, I’m calling on Therabody to do what’s right."

TMZ reached out to Therabody for comment ... so far, no word back.