What is the relationship between 'Turing Pharmaceuticals' and 'Martin Shkreli' in the context of the input sentence.
Options: position held, founded by, legal form, headquarters location

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