This from their web-site
Crowley was the first U.S. carrier to obtain a license from the Office of Foreign Assets Control (OFAC) of the United States Department of the Treasury in Washington, D.C., to provide regularly scheduled common carrier services for licensed cargo from the United States to the Republic of Cuba. Crowley launched its Cuba service in December 2001, becoming the first U.S. carrier to re-enter Cuba in nearly 40 years, and has maintained a regularly scheduled service ever since.
The opportunity to participate in the trade was made possible by the "Trade Sanctions Reform and Export Enhancement Act of 2000" signed into law on October 28, 2000 by William J. Clinton, President of the United States of America. The "Trade Sanctions Reform and Export Enhancement Act of 2000," authorizes OFAC to license the transport of agricultural commodities, medicine, medical devices or other products directly from the United States to the Republic of Cuba.
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