During the examination of the patent application, the Thai Department of Intellectual Property (DIP) allowed BMS to remove the limitation in the dosage range. In many patent offices it is allowable to amend a patent application, but only so long as certain rules are followed. If the amendment was allowed without following these rules, for example by mistake, and a patent granted, then the patent may be invalid. On January 22nd 1998, the Thai Patent Office granted a patent for this unlimited invention