Everything from intel on mercenary contracts to political blackmail to marital infidelity is game for the Broker, and as per the name, the Shadow Broker will buy, trade and sell secrets to anyone who will pay enough for them. Instead, the Broker is the galaxy's number one information broker, and no secret is safe from the Broker's many eyes and ears.
The Broker is not a planetary governor or the general of an army. In a sense, the Shadow Broker is a game master, and every power player in the galaxy is involved.