Brokers generally want to control access to their research. While they have understandable commercial reasons to reward their institutional investor clients, this means that, when company management take the time to brief City Analysts, this unfortunately does not work as a mechanism for disseminating company disclosure to the private investor population (as discussed here).
While this is unfair and discriminatory, it's not as bad as it might at first appear. This is because the signal from broker research has actually been shown to be quite limited and often misleading. Broker recommendations have historically exhibited a strong upward bias. Behavioural scientists have also shown repeatedly that experts in every field are poor forecasters, inaccurate, over confident and slow to change their opinion. As we discuss here, research analysts are no exception, with research by David Dreman showing the appalling track record of analyst forecasting:
In the US, the average 24-month forecast error [was] 93%, and the average 12-month forecast error [was] 47% over the period 2001-2006.