As appears from the expressions «the seller must» and «the buyer must» Incoterms are only concerned with the obligations which the parties owe to each other. The words «no obligation» have therefore been inserted whenever one party does not owe an obligation to the other party. Thus, if for instance according to A3 of the respective term the seller has to arrange and pay for the contract of carriage we find the words «no obligation» under the heading «contract of carriage» in B3 a) setting forth the buyer's position. Again, where neither party owes the other an obligation, the words «no obligation» will appear with respect to both parties, for example, with respect to insurance.
In either case, it is important to point out that even though one party may be under "no obligation" towards the other to perform a certain task, this does not mean that it is not in his interest to perform that task. Thus, for example, just because a CFR buyer owes his seller no duty to make a contract of insurance under B4, it is clearly in his interest to make such a contract, the seller being under no such obligation to procure insurance cover under A4.