This comfortable arrangement came to an end when the hous- ing market collapse raised concerns about the quality of all asset- backed investments, including securities issued by market funds soon stopped buying their CP. And then the doomsday sce- nario struck: when SIVs attempted sell a large part of their portfolio holdings to pay off the CP when it matured, they found that they couldn’t. Money market funds had to mark down the prices on any SIV- issued CP that they still owned, in the process threatening to break the buck. To keep that from happening, a number of fund sponsors provided support for the value of the SIV-issued.
