Way back when, President Eisenhower gave an S-58 to the Russian government to be used as an executive transport. Many people in the military establishment warned against it as it would give the Russians state of the art design technology that could eventually be used against the United States military. I don’t know if they ever used it for the intended purpose but if you look at the Russian helicopters I doubt if you will find anything that is obviously of American design influence or even remotely resembles the Sikorsky design.