Can you take the series 6 exam without being sponsored by an organization?

No, you cannot take the Series 6 exam without being sponsored by a firm that is a member of FINRA (Financial Industry Regulatory Authority). The exam is specifically for individuals who will be working in the securities industry in a registered capacity, and that requires being employed by, and sponsored by, a member firm. You need a sponsoring firm to register you for the exam, and they will be the ones who will receive the results.