The Iran and Libya Sanctions Act of 1996 (ILSA) was a 1996 act of Congress that imposed economic sanctions on firms doing business with Iran and Libya. On September 30, 2006, the act was renamed to the Iran Sanctions Act (ISA), as it no longer applied to Libya, and extended until December 31, 2011. As of March 2008, ISA sanctions had not been enforced against any non-US company; the act allows the president to waive sanctions on a case-by-case basis, though this waiver is subject to renewal every six months. Despite the restrictions on American investment in Iran, FIPPA provisions apply to all foreign investors, and many Iranian expatriates based in the US continue to make substantial investments in Iran.
This summary is from Wikipedia.
The summary below was written by the Congressional Research Service, which is a nonpartisan division of the Library of Congress.
7/16/1996--Passed Senate amended.
Iran and Libya Sanctions Act of 1996 - Declares U.S. policy with respect to Iran and Libya. (Sec. 4) Urges the President to commence diplomatic efforts with U.S. allies to establish multilateral trade sanctions against Iran, including limiting its development of petroleum resources, in order to end its ability to support acts of international terrorism and efforts to develop or acquire weapons of mass destruction. Requires the President to report periodically to the appropriate congressional committees on the extent of the success of such efforts. Authorizes the President to waive such sanctions if certain requirements are met. Requires the President to report to the appropriate congressional committees with respect to the imposition of trade sanctions on persons doing business or having investments in Iran or Libya by member states of the European Union, the Republic of Korea, Australia, Israel, or Japan. (Sec. 5) Directs the President to impose certain economic sanctions against persons who with actual knowledge have: (1) made an investment of $40 million or more in any 12-month period that directly contributes to Iran's or Libya's ability to develop its petroleum resources; or (2) exported to Libya any goods or technology prohibited by United Nations Security Council Resolution 748, adopted March 31, 1992, or Resolution 883, adopted November 11, 1993, which significantly contributed to Libya's ability to acquire chemical, biological, or nuclear weapons, develop petroleum resources, or maintain its aviation capabilities. Specifies exceptions to trade sanctions, among other things, for certain defense-related articles or services essential to U.S. national security. (Sec. 6) Authorizes the President, with respect to any sanctioned person, to: (1) direct the Export-Import Bank not to approve issuance of any guarantee, insurance, or credit extension for the export of goods or services to any sanctioned person; (2) order the U.S. Government to deny licenses or permits to a sanctioned person for the export of goods or technology; and (3) prohibit loans from U.S. financial institutions. Specifies sanctions that may be made against sanctioned persons that are financial institutions. (Sec. 7) Authorizes the Secretary of State, upon request, to issue an advisory opinion to any person as to whether a proposed activity would be subject to sanctions. (Sec. 8) Waives the requirements of this Act if the President certifies to the appropriate congressional committees that Iran has: (1) ceased its efforts to develop or acquire a nuclear explosive device, chemical or biological weapons, or ballistic missiles and missile launch technology; and (2) been removed from the list of countries determined, under the Export Administration Act of 1979, to have repeatedly supported acts of international terrorism. Waives the requirements of this Act with respect to Libya only if the President, in addition to the waiver determination, certifies to the appropriate congressional committees that Libya has fulfilled the requirements of the United Nations Security Council Resolution 731, adopted January 21, 1992, Resolution 748, adopted March 31, 1992, and Resolution 883, adopted November 11, 1993. (Sec. 9) Specifies circumstances in which the President may delay or waive sanctions, conditioned on certification to the Congress of certain facts. Prescribes a minimum two-year duration for sanctions. (Sec. 10) Requires the President to report periodically to the appropriate congressional committees on efforts to persuade other countries to: (1) pressure Iran to cease its nuclear, chemical, biological, and missile weapons programs and support of international terrorism; and (2) ask Iran to reduce the presence of Iranian diplomats and other personnel and withdraw any of them who participated in the takeover of the U.S. embassy in Tehran on November 4, 1979. Requires such report also to detail: (1) the extent to which the International Atomic Energy Agency has established regular inspections of all nuclear facilities in Iran; and (2) Iran's use of Iranian diplomats and representatives of other government and military or quasi-governmental institutions of Iran to promote acts of international terrorism or to develop Iran's nuclear, chemical, biological, and missile weapons programs. Requires the President to ensure continued reports to the Congress on Iran's: (1) nuclear and other military capabilities; and (2) support for acts of international terrorism. (Sec. 11) Declares that determinations to impose sanctions under this Act are not reviewable in any court.