Chinese Wall

n. Great Wall of China, 1,500 miles long wall which is the world's longest system of fortified walls which was built in the 3rd century BC by the Ch'in dynasty (located in northern China)

n. barrier that hinders the passing of information; insuperable obstacle; set of severe rules implemented within firms (such as a financial institution, etc.) which are meant to prevent the exchange of top secret information between the different divisions as to avoid conflict of interest

In business, Chinese Walls are information barriers implemented within firms to separate and isolate persons who make investment decisions from persons who are privy to undisclosed material information which may influence those decisions. In general, all firms are required to develop, implement and enforce reasonable policies and procedures to safeguard insider information, and to ensure no improper trading occurs. Although specific procedures are not mandated, adopted practices must be formalized in writing and must be appropriate and sufficient. Procedures should address the following areas: education of employees, containment of inside information, restriction of transactions, and trading surveillance.
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Noun
1. a fortification 1,500 miles long built across northern China in the 3rd century BC; is 1,500 miles long and averages 6 meters in width
(synonym) Great Wall, Great Wall of China
(hypernym) rampart, bulwark, wall
(part-holonym) China, People's Republic of China, mainland China, Communist China, Red China, PRC

Communication barrier between financiers (investment bankers) and traders. This barrier is erected to prevent the sharing of inside information that bankers are likely to have.

A screening barricade established within a law firm to prevent conflicts of interests between associates. - (read more on Chinese Wall)