Before statutory mercantile reforms, such assignments were unenforceable at law unless both assignor and assignee participated in the claim. An arbitration clause in a charterparty is little value if a necessary party is not in privity with the submission to arbitration. Guarantees frequently are given in maritime commerce. Before statutory mercantile reforms, a guarantors' payment of the debt was regarded as a complete discharge, leaving the guarantor without a right to claim over against the original debtor or any co-surety. There is no federal equivalent.
Maritime commerce is replete with agents.
At common law a judgment against or settlement with one of several persons having a joint obligation, such as a principal and its agent, discharged any right to claim against any of the other persons jointly liable. This doctrine of merger discourages settlements with one of several defendants and can leave a creditor without effective recovery if it obtains an award against a judgment proof joint defendant. While a covenant not to sue, as distinct from a release, may not trigger the merger trap, in the absence of an updated common law rule, claimants may still be faced with a lottery in choosing which joint defendant against whom to obtain an award. It may still haunt non-statutory Canadian Maritime Law unless tribunals are prepared to update the law. This is doubtful after Ordon v. Grail .