(n) buying or selling corporate stock by a corporate officer or other insider on the basis of information that has not been made public and is supposed to remain confidential
The Collaborative International Dictionary of English (GCIDE) v.0.53 Collaborative International Dictionary (GCIDE)
n. an officer of a corporation or others who have access to private information about the corporation's operations, especially information relating to profitability. An insider is forbidden by U. S. securities laws to trade stock in publicly owned corporations based on the private information. The definition of insider for the purpose of securities law has changed in the late 29th century to become more inclusive, whereas it initially was applied only to officers of a corporation. [ WordNet 1.5 +PJC ]
[走内线 / 走內線, zǒu nèi xiànㄗㄡˇ ㄋㄟˋ ㄒㄧㄢˋ] insider contacts; via private channels; to seek influence with sb via family members (possibly dishonest or underhand)#387203