Utilize the input text as a context reference, choose the right relationship between 'Turing Pharmaceuticals' and 'Martin Shkreli' from the options.
Options: legal form, headquarters location, founded by, position held

News (Other OTC: NWSAL - news ) headlines proclaimed Turing Pharmaceuticals CEO Martin Shkreli the "most hated man in America," and he soon vowed to roll back the price, but did not say by how much.
founded by