When a creditor charges off a debt, the creditor is entitled to deduct the charged off amount from its tax returns. Since the typical large corporation pays a marginal 35% federal tax on its earnings, negotiating for less than 35% is a waste of time, because the creditor can do better without negotiating with you at all. If the creditor is subject to state income tax as well as to federal, then the two taxes
must be considered. IBM is headquartered in Florida, which has a 5.5% state income tax rate. Consequently, any offer of less than 40.5% will be summarily rejected, because it exceeds the corporation's tax charge off rate.
If the creditor is asking for more than that, then it's simply because the creditor wants some sort of profit for its efforts. A 10% profit is reasonable, which would bring you to approximately 50%. Unless you threaten to file Chapter 7
bankruptcy, you are unlikely to be able to negotiate below 50% with your target creditor. Sometimes, the threat of bankruptcy will cause a creditor to substantially reduce its offer. But, even if you threaten bankruptcy, your target creditor would never have an incentive to negotiate below 40.5% -- which is its marginal tax rate on revenue.
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