While the core tenets of insider trading law are well-established, the outer bounds of the law are continuously evolving, and the application of established doctrine to hedge fund industry-specific issues remains a challenge for many managers.  This article is the first in a two-part series designed to serve as a guide for hedge fund managers to the laws, regulations and cases that define the scope and contours of relevant insider trading doctrine.  Specifically, this first article discusses important elements of insider trading liability, including what constitutes nonpublic information; what information is considered material; when a fiduciary duty has been breached; and the mosaic theory of insider trading.  The second installment will discuss the misappropriation theory of insider trading; the element of scienter; insider trading consequences of fund investments by affiliates of portfolio companies; special tender offer rules; and penalties.  The author of this article series is Ralph Siciliano, a partner at Tannenbaum Helpern Syracuse & Hirschtritt LLP, and head of the firm’s Governmental and Regulatory Investigations Practice.