The IRS may accept an OIC for one of the 3 following reasons (www.irs.gov/taxtopics/tc204):
“First, the IRS can accept a compromise if there is doubt as to liability. A compromise meets this criterion only when there’s a genuine dispute as to the existence or amount of the correct tax debt under the law.
Second, the IRS can accept a compromise if there is doubt that the amount owed is fully collectible. Doubt as to collectibility exists in any case where the taxpayer’s assets and income are less than the full amount of the tax liability.