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My headhunter sent me an e-mail saying that there is a job opening at xx company. Later I saw LinkedIn posting it (it was recommended to me "this companies are looking for candidates like you"). Should I apply for it via LinkedIn, or should I wait for my headhunter to submit my resume? If I apply for it online and then the headhunter also submit my resume for me, and if I end up getting the job, would the company reject to pay headhunter commission?