Under regulation of the first clause of Article 22 of the patent law, any invention can be useful for production is patentable by this law unless:

1. The invention had been presented in public exhibition or published in the official gazet before filing date of the application.

2. The invention was well known to the public before filing date of the application.

Moreover, under regulation in second clause of Article 22 of the patent law, if an ordinary skilled person may easily accomplish the invention sought to be patented based on prior known technology or knowledge, then the invention is not patentable even if it complies with the first clause of Article 22 of the patent law mentioned above.

As for this reason, it is essential that a patentable invention shall fulfill the conditions set forth below known as the three basic requirements of the patentability in Taiwan.

1. Productivity
2. Novelty
3. Non-obviousness