We model stock price manipulation when the manipulator is in the role of an intermediary (broker). We find that in the absence of superior information, the broker can manipulate equilibrium outcomes without losing credibility with respect to accurate forecasting. This result extends to the case when the broker prefers more investment to come into the market. However, when competition among brokers is introduced then the investors get their favorite outcome in the absence of superior information. This result has important implications for encouraging broker competitions in developing markets. Many developing markets are still not demutualized; hence broker level competition is limited in such markets.