是沒有正式擔保的, 有模糊的沒有法律效力的所謂“implicit”擔保，

Government-sponsored Enterprise securities (GSEs) are issued by government-created corporations and most carry “AAA” or “AA” ratings.

Major issuers are:

• Fannie Mae (Federal National Mortgage Association)
• Freddie Mac (Federal Home Loan Mortgage Corporation)
• Ginnie Mae (Government National Mortgage Association), – whose securities are backed by the full faith and credit of the U.S. government; subject to market risk

Both Fannie Mae and Freddie Mac are government-sponsored entities and operate as public companies. Although both were created by congressional charters, neither is a government agency. Timely payments of interest and principal are sole obligations of the issuers. Their securities do not constitute debt of the United States and are not guaranteed by the federal government. Fannie Mae and Freddie Mac are presently under the Federal Housing Finance Agency’s conservatorship. During the conservatorship, both enterprises will continue normal business operations, including interest and principal payments. For more information, please visit fhfa.gov.

 

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