Jones (“Jones”). Finally, you sometimes see the validity date used in a contract to refer to a date in the past. For example, parties to a distribution agreement signed on 31 March 2007 may wish to have sales included from 1 January 2007 for the purpose of calculating 2007 sales. It would be easier and clearer to say the same instead of using the term date of entry into force and defining it to mean 1 January 2007. It is customary to recall in a contract the effectiveness of something or another – perhaps a merger or a declaration of registration. This is not to complain. But I doubt that I will use the defined notion of a date of entry into force in a treaty to underline the effectiveness of that treaty. Sometimes the parties use the effective date to refer to a future date when either agreement occurs. . . .