Depends on what exactly you call difficult. If there are issues with plagiarism in a product, that's one difficulty, but if a patent has not been registered and someone else is using it, that's an other one. I think in that situation you need to contact a reputable
tech lawyer in Los Angeles, like David Sharifi. He has been working with different requests for about 20 years and has a tremendous experience. In any case, your cooperation will start with a consultation, during which you can discuss all the points with him.