An analyst who lends his or her expertise to an underwriting department is said to have been "brought over the wall". In financial firms, the separation between the investment analyst and the underwriting departments is described as the "wall", as in the Great Wall of China. The division exists as an ethical boundary to guard against the exchange of insider information between the two departments.

Bringing an employee from the research department of an investment bank "over the wall" is common practice. The research analyst lends his or her knowledgeable opinion about the company so that the underwriters are better informed during the underwriting process. After the process has been completed, the research analyst is restricted from sharing any information about his or her time "over the wall" until the information has been made public - another measure toward preventing the exchange of insider information.

This question was answered by Bob Schneider.