this seems to sum up the root of his problem:
Our team pitched them on a new project we created just for Kim called "Kimoji." Kim and her team agreed to be equal partners on Kimoji and split Censorgram 60-40% us. Everyone was excited after this meeting and Kim's team verbally agreed to sign off on both projects, with pending net contracts to come......Kim called us and asked if our team had filed a trademark and told us that her team would file it for us. Sadly, that never happened. Kim's team filed the trademark behind our back and cut us out of the deal completely.
Unjust enrichment?
A verbal agreement isn’t worth the paper it’s written on. What you are supposed to do is first draft a letter of understanding, then proceed from there to negotiate the final contract.
https://en.wikipedia.org/wiki/Letter_of_understanding
This story reminds me of a cab driver where I lived 35 years ago. He was an older black man, and he carried a large file of documents with him in the taxi. Every time I got into his cab, he shared his story and showed this paperwork. He must’ve told every passenger the same story:
He’d invented a quality brand of baby diapers. He sent his idea with diagrams to a large diaper company and asked if they were interested, and he filed for a patent. The company sent him a rejection letter and filed for a patent for the same idea. Guess who got the patent - not the cab driver. So, he filed a lawsuit, showing he’d sent his idea to the company before it filed for a patent. He argued that he was the inventor, so he should have the patent. The company argued they’d already come up with the idea on their own, and they just happened to file the patent after they received his diagrams. The poor guy kept losing to this big, powerful company.