|FEDERAL NATIONAL MORTGAGE ASSOCIATION FANNIE MAE filed this Form 10-Q on 08/05/2011|
$648 million as of December 31, 2010 was due from our mortgage seller/servicers. We assessed the total outstanding receivables for collectibility, and they were recorded net of a valuation allowance of $253 million as of June 30, 2011 and $317 million as of December 31, 2010 in Other assets. These mortgage insurance receivables are short-term in nature, having a duration of approximately three to six months, and the valuation allowance reduces our claim receivable to the amount that we consider probable of collection. We received proceeds under our primary and pool mortgage insurance policies for single-family loans of $1.5 billion for the second quarter of 2011, $3.1 billion for the first half of 2011 and $6.4 billion for the year ended December 31, 2010.
We were the beneficiary of financial guarantees totaling $8.3 billion as of June 30, 2011 and $8.8 billion as of December 31, 2010 on securities held in our investment portfolio or on securities that have been resecuritized to include a Fannie Mae guaranty and sold to third parties. The securities covered by these guarantees consist primarily of private-label mortgage-related securities and mortgage revenue bonds. We are also the beneficiary of financial guarantees issued by Freddie Mac, the federal government and its agencies included in securities that totaled $31.8 billion as of June 30, 2011 and $25.7 billion as of December 31, 2010.
With the exception of Ambac Assurance Corporation, none of our financial guarantor counterparties has failed to repay us for claims under guaranty contracts. However, based on the stressed financial condition of our financial guarantor counterparties, we believe that one or more of our other financial guarantor counterparties may not be able to fully meet their obligations to us in the future. We model our securities assuming the benefit of those external financial guarantees from guarantors that we determine are creditworthy. For additional discussions of our model methodology and key inputs used to estimate other-than-temporary impairment see Note 5, Investments in Securities.
Lenders with Risk Sharing
We enter into risk sharing agreements with lenders pursuant to which the lenders agree to bear all or some portion of the credit losses on the covered loans. Our maximum potential loss recovery from lenders under these risk sharing agreements on single-family loans was $14.3 billion as of June 30, 2011 and $15.6 billion as of December 31, 2010. As of both June 30, 2011 and December 31, 2010, 56% of our maximum potential loss recovery on single-family loans was from three lenders. Our maximum potential loss recovery from lenders under these risk sharing agreements on multifamily loans was $31.1 billion as of June 30, 2011 and $30.3 billion as of December 31, 2010. As of June 30, 2011, 40% of our maximum potential loss recovery on multifamily loans was from three lenders. As of December 31, 2010, 41% of our maximum potential loss recovery on multifamily loans was from three lenders.
Unfavorable market conditions have adversely affected, and continue to adversely affect, the liquidity and financial condition of our lender counterparties. The percentage of single-family recourse obligations to lenders with investment grade credit ratings (based on the lower of S&P, Moodys and Fitch ratings) was 48% as of June 30, 2011 and 46% as of December 31, 2010. The percentage of these recourse obligations to lender counterparties rated below investment grade was 23% as of both June 30, 2011 and December 31, 2010. The remaining percentage of these recourse obligations were to lender counterparties that were not rated by rating agencies, which was 29% as of June 30, 2011 and 31% as of December 31, 2010. Given the stressed financial condition of some of our lenders, we expect in some cases we will recover less, perhaps significantly less, than the amount the lender is obligated to provide us under our risk sharing arrangement with them. Depending on the financial strength of the counterparty, we may require a lender to pledge collateral to secure its recourse obligations.
As noted above in Multifamily Credit Risk Management, our primary multifamily delivery channel is our DUS program, which is comprised of lenders that span the spectrum from large depositories to independent non-bank financial institutions. As of June 30, 2011, approximately 54% of the unpaid principal balance of loans in our multifamily guaranty book of business serviced by our DUS lenders were from institutions with an external investment grade credit rating or a guarantee from an affiliate with an external investment grade