In the UK, the relevant laws are the Financial Services Act 1986 and the Financial Services and Markets Act 2000, which defines an offense of Market Abuse. [3] It is not illegal to fail to trade based on inside information (whereas without the inside information the trade would have taken place), since from a practical point of view this is too difficult to enforce. It is often legal to deal ahead of a takeover bid, where a party deliberately buys shares in a company in the knowledge that it will be launching a takeover bid.

Japan enacted its first law against insider trading in 1988. Roderick Seeman says: "Even today many Japanese do not understand why this is illegal. Indeed, previously it was regarded as common sense to make a profit from your knowledge." [4].

In accordance with EU Directives, Malta enacted the Financial Markets Abuse Act in 2002, which effectively replaced the Insider Dealing and Market Abuse Act of 1994.

The "Objectives and Principles of Securities Regulation" [5] published by the International Organization of Securities Commissions (IOSCO) in 1998 and updated in 2003 states that the three objectives of good securities market regulation are (1) investor protection, (2) ensuring that markets are fair, efficient and transparent, and (3) reducing systemic risk. The discussion of these "Core Principles" state that "investor protection" in this context means "Investors should be protected from misleading, manipulative or fraudulent practices, including insider trading, front running or trading ahead of customers and the misuse of client assets." More than 85 percent of the world's securities and commodities market regulators are members of IOSCO and have signed on to these Core Principles.

The World Bank and International Monetary Fund now use the IOSCO Core Principles in reviewing the financial health of different country's regulatory systems as part of these organization's financial sector assessment program, so laws against insider trading based on non-public information are now expected by the international community. Enforcement of insider trading laws varies widely from country to country, but the vast majority of jurisdictions now outlaw the practice, at least in principle.