Cato Institute http://www.sourcewatch.org/index.php?title=Cato_Institute

The Cato Institute is a non-partisan libertarian think tank headquartered in Washington, D.C. Cato was founded in 1977 by Edward H. Crane and Charles Koch, [2] the billionaire co-owner of Koch Industries; the largest privately owned company in the United States. Though diversified, the company amassed most of its fortune in oil trading and refining

Aside from its own advocacy efforts, the Cato Institute has become a substantial funder of other "like-minded" think tanks around the U.S. In its 2006 annual report Cato lists 26 organizations and one individual it provided grants totaling $1,243,00 to. Groups the benefited from Cato's generosity were Agencia Americana ($30,000 "to help fund study on S.A. corruption"); the Philanthropy Roundtable ($5,000); the Manhattan Institute ($5,000); the American Enterprise Institute ($5,000); the Fund for American Studies ($10,000); the Bluegrass Institute ($50,000); the Cascade Policy Institute ($25,000); the Ethan Allen Institute ($50,000); the Evergreen Freedom Foundation ($100,000); the Grassroot Institute of Hawaii ($40,000); the Illinois Policy Institute ($50,000); the James Madison Institute ($100,000); the John Locke Foundation ($20,000); the Maine Heritage Policy Center ($50,000); the Maryland Public Policy Institute ($40,000); the Nevada Policy Research Institute ($50,000); the Oklahoma Council of Public Affairs ($50,000); the Rio Grande Foundation ($50,000); the Show-Me Institute ($50,000); the South Carolina Policy Council ($90,000); the Sutherland Institute ($40,000); the Tennessee Center for Policy Research ($50,000); the Texas Public Policy Foundation ($100,000); the Virginia Institute for Public Policy ($25,000); the Yankee Institute ($68,000); and the Independent Institute ($60,000). In addition Jim Powell received $25,000 as a Hoiles Fellowship.[12] (note, the Cato annual report refers to the "South Carolina Policy Institute" when the correct name of the think tank is the "South Carolina Policy Council". Similarly, the Maryland Public Policy Institute was misidentified as the Maryland Public Policy Center.

In 2006 Cato raised approximately $612,000 from the following 26 corporate supporters:
Altria (the report identifies Altria Corporate Services as the contributor)
American Petroleum Institute
Amerisure Companies
Amgen
Chicago Mercantile Exchange
Comcast Corporation
Consumer Electronic Association
Ebay Inc
ExxonMobil
FedEx Corporation
Freedom Communications
General Motors
Honda North America
Korea International Trade Association
Microsoft
National Association of Software and Service Companies
Pepco Holdings Inc.
R.J. Reynolds Tobacco Company
TimeWarner
Toyota Motor Corporation
UST Inc
Verisign
Verizon Communications
Visa USA Inc
Volkswagen of America
Wal-Mart Stores