The Supreme Court’s Unification Rulings concerning the recoverability of delay damages after the cessation of payments by a bankrupt merchant have become increasingly open to critical examination in light of the substantive transformation of this legal institution. The continued reliance on the ruling that categorically denied the recovery of delay damages after the date of cessation of payments (Unification Ruling No. 155), alongside the emergence of more recent rulings adopting a different approach, has highlighted the need for a critical reappraisal of this line of jurisprudence. This study examines the following question: How has the substantive transformation of delay damages affected the continuing validity of Unification Ruling No. 155 and the subsequent rulings based upon it, and to what extent have the more recent unification rulings altered this judicial approach? The findings demonstrate that Unification Ruling No. 155 was coherent and justifiable at the time of its issuance, given that delay damages under the pre-Revolutionary legal framework were conceived primarily as a statutory penalty. However, following the enactment of Article 522 of the Civil Procedure Code, which redefined delay damages as a mechanism for compensating the depreciation of money and preserving the real value of monetary claims, the continued adherence to the rule of absolute non-recoverability reflected in subsequent Unification Rulings Nos. 788 and 872 is no longer compatible with the contemporary legal framework. By contrast, the Supreme Court’s more recent jurisprudence, particularly Unification Ruling No. 877, recognizes the necessity of preserving the real value of creditors’ claims by allowing compensation for the depreciation of monetary obligations where surplus assets remain after the settlement of bankruptcy debts, thereby reflecting a substantive shift in the Court’s underlying legal reasoning. Accordingly, this study concludes that Unification Ruling No. 877, by recognizing the recoverability of the depreciation of monetary claims where surplus assets exist, provides a sound legal basis for departing from the reasoning underlying Unification Ruling No. 155 and the decisions founded upon it. Consequently, rather than continuing to rely on the earlier rulings, judicial practice should be realigned with the approach adopted in Unification Ruling No. 877, and the liability of guarantors as well as directors and authorized signatories of bankrupt companies should likewise be reassessed in light of this doctrinal development.