A more thorough explanation:

The Deep Rock Doctrine is a principle used in bankruptcy cases to ensure that the claims of general or trade creditors are given priority over those of controlling shareholders who may have made unfair or inequitable claims.

For example, if a bankrupt corporation's controlling shareholder tries to claim a large portion of the company's assets for themselves, the Deep Rock Doctrine would allow the court to subjugate that claim in favor of the claims of other creditors who are owed money by the corporation.

The doctrine is named after a case involving the Deep Rock Oil Corporation, which made fraudulent transfers to its parent company. In Taylor v. Standard Gas & Elec. Co., the Supreme Court ruled that the claims of the parent company could be subordinated to those of other creditors under the Deep Rock Doctrine.