Filing a successful proof of claim is the key to unlocking a creditor's right to recover against a debtor in bankruptcy. Only in limited circumstances may a creditor recover against the debtor's estate without properly filing a proof of claim. This article addresses the various stages of filing, attacking and defending a proof of claim.

One week after Aegis Mortgage Corp. filed for chapter 11 in Delaware, a group of former employees filed their complaint seeking class certification over allegations that Aegis Mortgage Corporation, Aegis Wholesale Corporation and Cerberus Capital Management, L.P.—all allegedly acting as their employer—violated the Worker Adjustment and Retraining Notification (WARN) Act when they failed to give over 400 employees 60 days' notice prior to a mass termination by Aegis Mortgage on August 7, 2007.