The repeal of secondary sanctions have for the most part have been lifted. This opens the way for European countries allied with the United States to resume trade with Iran and invest in the Iranian economy. However, almost all sanctions which make it illegal for American citizens to do the same remain in place. While Iran may resume the import of caviar, rugs, and pistachios to the U.S. market, little else will be permitted. One key exception to this is American airline manufacturing companies like Boeing will be permitted to sell commercial aircraft to Iran. Other products which may be legally exported to Iran are medical supplies, pharmaceuticals, and some consumer technical devices. However, all sales by American enterprises to Iran will require a United States Treasury Authorization Stamp. Nevertheless, for most other commodities, U.S. companies will must have their foreign subsidiaries engage in bilateral commerce.