1. Public/national debts vis-à-vis third parties
Absorption (German unification)/merger (Tanzania): the expanding (the German Federal Republic) or newly created State (Tanzania) takes over the national debt of the extinguished State/s (the former DDR and Tanganica/Zanzibar respectively)
Secession where the predecessor State continues to exist (e.g. Sudan-South Sudan): the responsibility remains with the predecessor State unless an allocation between the two has been agreed upon; however, debts that are linked to the successor State’s territory pass to the latter
Dismemberment and dissolution: equitable apportionment of public debts by way of agreement; however, debts that are linked to the successor State’s territory pass to the latter

2. Debts/liquidated damages vis-à-vis private creditors
In general, debts vis-à-vis private creditors pass to the successor State (although an agreement settling the matter is desirable)
However, in case of absorption or dissolution, liability for any wrong committed by the absorbed State ends (unless the expanding/successor State adopts the illegal actions of the absorbed/pre-existing State) and private parties can no longer pursue their claims on this ground