not anticipated by the bond insurers or the rating agencies that evaluated their creditworthiness. Unlike many other types of insurance, bond insurance generally provides an unconditional and irrevocable guaranty—although the insurers reserve the right to pursue contractual and other available remedies. As a result, the bond insurers faced billions of dollars of claims on insured RMBS, with uncertain prospects for recoveries from the sponsors (creators) of those RMBS. Monoline insurers posted higher reserves for losses as these insured securities appeared headed for default. Following the crisis, the bond insurers became aware that many RMBS they had insured included large percentages of loans that were ineligible for securitization, i.e., they should not have been in the RMBS and were subject to repurchase by the RMBS sponsors. As provided under the insurance contracts, the insurers "put back" to the sponsors such loans, which breached applicable representations and warranties ("R&W") regarding what was in the securitizations, i.e., they demanded the sponsors buy the loans out of the pool, as required under the contracts. Such "putbacks" have remained subject to litigation into the second decade following the financial crisis. One indication of the extent of loan quality misrepresentation was a 2011 settlement between Assured Guaranty and Bank of America, which had purchased mortgage originator Countrywide. Under the terms of the settlement, Bank of America made a $1.1 billion payment to Assured Guaranty and agreed to cover 80% of up to $6.6 billion of Assured Guaranty's future paid losses from breaches of representations and warranties on 21 insured RMBS transactions. Subsequently, in 2013, in the first R&W trial to reach a judgment, Flagstar Bank was required to compensate Assured Guaranty in full for past and future claims. The amounts that Assured Guaranty caused R&W providers to pay or commit to pay through putbacks and settlements plus the amount of future projected losses that Assured Guaranty avoided through negotiated terminations totaled approximately $4.2 billion as of March 31, 2015. While the widespread misrepresentations caused bond insurers to experience considerable losses on insured securities backed by residential mortgage loans (including first lien loans, second lien loans, and home equity lines of credit), the most severe losses were experienced by those that insured CDOs backed by mezzanine RMBS. Although the bond insurers generally insured such CDOs at very high attachment points or collateral levels (with underlying ratings of triple-A), those bond insurers and the rating agencies failed to