In economics, intragovernmental holdings (also known as intragovernmental debt or intragovernmental obligations) are Government Account Series (GAS) securities held by government trust funds, revolving funds and special funds.
Intragovernmental debt is incurred when the government borrows from federal trust funds to help fund current operations.
United States
In the United States, intragovernmental holdings are primarily composed of the Medicare Trust Fund, the Social Security Trust Fund, and Federal Financing Bank securities. A small amount of marketable securities are held by government accounts.
The value of intragovernmental debt holdings as of February 21, 2017 is $5,531,705,453,238.55
References
Intragovernmental holdings Wikipedia(Text) CC BY-SA