although the mailbox obligation does not affect the ldc members right to refuse to issue or enforce patents on pharmaceutical products until it does require them to install and maintain administrative procedures that permit the receipt and retention of pending pharmaceutical patent applications for the purpose of later examination ie from on that decision extended the transition period under trips article in the decision on the extension expressly refers to the ldc transition period under article of the agreement ie the transition period that had to respect the mailbox obligation under article a this reference has to be understood as carrying over into the original mailbox obligation under the original transition period