In accordance with Taiwan's Patent Act, a patent may not be obtained if the distinctions between an invention sought to be patented and the located prior art references are such that the invention as a whole would have been obvious at the time the invention was made to a person having ordinary skill in the art to which the invention pertains.  Moreover, to establish a prima facie case of obviousness in a patent application, an invalidation action or a patent infringement lawsuit, the Examiner or Judge is obliged to show that there is some teaching, suggestion, or motivation in the prior art that would have led a person having ordinary skill in the art to combine prior art reference teachings to arrive at the claimed invention.  

As a general rule, when considering the obviousness of the combination of the prior art references, the Examiner or Judge should evaluate if the primary prior art reference and the other references located to cure the deficiency of the primary reference are in analogous fields of art, have common problems to be solved and serve the same or similar intended purpose.  To illustrate the implications of this principle, Taiwan's IP Office published in 2017 a revised Examination Framework regarding the "inventive step" of an invention, which provides, among others, a four-prong test to determine whether there would be a "reasonable motivation" for a  person having ordinary skill in the art to combine the relevant located references. The test permits the consideration of four parameters, namely, (1) whether the located prior art references belong to analogous fields of art; (2) whether the problems sought to be solved are common; (3) whether the references have common functionality; and (4) whether any explicit or implied teaching or suggestion can be found in the state-of-the-art or the knowledge of a person having ordinary skill in the art and enables the person to combine the located references. 

While it is valuable to have a closer look at the interrelations among the four parameters and how they are applied to actual cases, alone or in combination, the Judges of the Supreme Administrative Court have recently expressed their consensus opinion in a Ruling rendered on a Patent Invalidation Case as follows:

  1. In the determination of whether a plurality of prior art references have common functionality, consideration should be given to the "overall structure" rather than the "common structure" of the relevant devices. 

The patented invention under invalidation is related to an electric fan and its manufacturing method, the main technical feature of which resides in an improved method for combining a fan transit shaft and a metal shell.  As for the five prior art references cited by the invalidation petitioner against the validity of the patent, the primary reference 1 is related to a "spindle motor", and the other references 2, 3 and 5 are all in the field of "electric fans".

The IP Court's Ruling decided that reference 1 can be combined with reference 2 or 3 in an obvious manner. The main reasons are: "[t]he devices disclosed in reference 1 and reference 2 or 3 have common functionality. First, the device disclosed in either references 1 or 2 has a rotor and a stator which can drive the spindle to rotate and in turn allow the external carrier to rotate.  Second, references 1 and 3 both relate to the use of the motor principles to allow external carriers or impellers to rotate."

Nonetheless, in the determination of whether a plurality of references have common functionality, consideration should be accorded to not only the function of the "common structure" of the devices disclosed in the references but also the function of the "overall structure" thereof.   While reference 1 has disclosed "a spindle motor installed on a device such as HDD, optical disk, optical magnetic disk, or magnetic disk", references 2 and 3 are both related to "electric fans". Apparently, the device disclosed in reference 1 is in a field not analogous to the field to which the device disclosed in reference 2 or 3 belongs.  Although the devices disclosed in reference 1, 2 and 3 have a common motor mechanism for rotation, the overall structure, and the manufacturing method disclosed in reference 1 have nothing to do with the disclosure in reference 2 or 3.  These distinctions are not too minute to be noticed, especially when the purpose intended to be served by reference 1 is not the same as that intended by reference 2 or 3.

Reference 1 has disclosed a spindle motor with a durable bearing, which was invented with a view to acquiring a high impact resistance effect, whereas reference 2 is related to a fan motor with an improved heat-dissipation effect.  It is not inappropriate for the patentee to aver that there would not be a reasonable motivation for a person having ordinary skill in the art to combine these two references serving totally different purposes. 

  1. A more stringent standard should be adopted in the determination of whether the problems to be solved by a plurality of references are "common."  To be more specific, the problems intended to be solved need to be substantially the same, rather than being merely related.

The IP Court found that reference 5, as well as references 2 and 3 are in the same technical field.  Further, as the problems intended to be solved by references 1 and 5, respectively, are related, there should be a reasonable motivation for a person having ordinary skill in the art to combine them.  However, such conclusion is apparently against the criteria set out in the Examination Framework published by the IP Office, which provide that a reasonable motivation to combine a plurality of references is existent only if the problems intended to be solved thereby, respectively, are substantially identical.

This precedent suggests a higher threshold to be met in establishing a prima facie case of obviousness. It is worth observing whether there will be future cases giving support to the Supreme Administrative Court's finding regarding the combination of the prior art references.

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