Date: 13 January, 2020

【Volume 20】

This recent Taiwan Intellectual Property Court case centers on the determination of non-obviousness in Taiwan patent practice.

Case Fact

The disputed patent, Taiwan invention patent no. I316092 “ALLOY AND ITS USE” (the ‘092 patent), was owned by Materion Advanced Materials Germany GmbH (Materion), which is the patentee and plaintiff of the case.

The patent was being challenged for invalidation before the Taiwan Intellectual Property Office (IPO). Materion specified a further limitation to Claim 1 in a post-grant amendment in response to the invalidation; however, the patent was still declared invalid by the IPO. Materion then filed an appeal to the Ministry of Economic Affairs, which was also rejected. An administrative litigation was therefore filed by Materion before the Intellectual Property Court, and the court dismissed the case.

Technical Features of the ‘092 Patent and the Citation

1. Technical features of the ‘092 patent:

   i. Claim 1:

   A sputtering target utilizing an alloy based on silver, comprising about 0.01 to 5 wt % of indium and/or antimony and/or bismuth; wherein a remainder of the alloy consists of silver; and wherein said alloy is not silver-2.5atm% indium or silver-0.5atm% antimony.

   ii. The main technical feature: An alloy based on silver which can be used for reflective layers with a reflection factor of >90% in the visible spectral range of daylight and which exhibits a high resistance to corrosion in sulfur-containing atmospheres.

2. Technical features of Citation 5:

   i. The main technical feature: A silver-based alloy thin film provided for the highly reflective or semi-reflective coating layer of optical discs, wherein said alloy additions to silver include zinc, aluminum, zinc plus aluminum, manganese, germanium, and copper plus manganese, and wherein said alloys have moderate to high reflectivity and reasonable corrosion resistance in the ambient environment.

   ii. Table 2 in the Specification:

   Composition	T0	R0	R1	R
   Ag-2.5%In	0.500	0.212	0.208	0.91
   Ag -1.2%Cr	0.535	0.243	0.238	0.94
   Ag -0.7%Ge	0.515	0.220	0.220	0.92
   Ag -1.0%Sn	0.504	0.216	0.211	0.92
   Ag -0.5%Sb	0.520	0.224	0.224	0.93
   Ag -3.0%Ga	0.475	0.195	0.187	0.86
   Ag -1.5%Si	0.490	0.202	0.199	0.90
   Ag -1.2%B	0.513	0.247	0.218	0.92
   Ag -0.8%Mo	0.515	0.220	0.218	0.92

    

3. Comparison of technical features of Claim 1 and Citation 5:

   Claim 1 in The ‘092 patent	Citation 5
   A sputtering target utilizing an alloy based on silver,	A metal alloy used as a highly reflective layer or as a semi-reflective layer in an optical storage medium can be used for thin film reflective layers that have high reflectivity and similar scattering characteristics as gold and are corrosion resistant and yet inexpensive, as stated in Line 2 from the bottom of Page 11 to Line 1 of Page 12 in Specification. A silver-based alloy thin film can be deposited by sputtering, as stated in Paragraph 2 of Page 35 to Page 36 in Specification.
   comprising about 0.01 to 5 wt % of indium and/or antimony and/or bismuth; wherein a remainder of the alloy consists of silver; and wherein said alloy is not silver-2.5atm% indium or silver-0.5atm% antimony.	The alloys may be still further alloyed with a metal such as nickel (Ni), indium (In), chromium (Cr), germanium (Ge), tin (Sn), antimony (Sb), gallium (Ga), silicon (Si), boron (B), zirconium (Zr), molybdenum (Mo), and mixtures thereof, and in relation to the amount of silver that is present in the silver alloy system, the amount of these metals that may be preferably added ranges from about 0.01 a/o percent to about 5.0 a/o of the amount of silver present, as stated in the last paragraph of Page 31 in Specification. Embodiments of “silver-2.5% indium” and “silver-0.5% antimony” in Table 2.

    

Materion’s Arguments

We summarize the arguments raised by Mateion during the litigation:

1. Citation 5 did not disclose the characteristic “alloying of silver and other elements” of Claim 1

   Materion argued that the composition of the alloy, “comprising indium and/or antimony and/or bismuth; wherein a remainder of the alloy consists of silver”, was disclosed in the close-ended Claim 1 of the ‘092 patent and did not include other uncited metals. However, according to the last paragraph of Page 31 in Citation 5, Citation 5 merely taught a general composition of a silver-based alloy might include various possible combinations for a person skilled in the art. Materion claimed that the different composition and proportion of the silver alloy would materially affect the characteristic of the alloy and the related reflective layers; therefore, a person skilled in the art would need numerous trials of the experiment to achieve the specific composition of the claimed invention. Additionally, a silver-based sputtering target is expensive and carelessness in experiments might lead to a risk of spending high costs.

2. Hindsight Bias of the IPO Judgement

   Materion claimed that in view of Citation 5, a person skilled in the art must deliberately select certain elements to alloy with silver, such as nickel (Ni), indium (In), chromium (Cr), germanium (Ge), tin (Sn), antimony (Sb), gallium (Ga), silicon (Si), boron (B), zirconium (Zr), molybdenum (Mo), and mixtures thereof, in order to produce the invention. He/she must further deliberately select In and/or Sb from said elements. The multiple deliberate selections were apparently based on hindsight after reading the ‘092 patent.

3. Citation 5 Teaches Away

   The abstract in Citation 5 disclosed that “the alloy additions to silver include zinc, aluminum, zinc plus aluminum, manganese, germanium, and copper plus manganese” and the elements could change the corrosion resistance. However, the ‘092 patent disclosed a layer comprising AgPd1Cu1 has less resistance to corrosion resistance in a comparative example. Materion claimed that Citation 5 constituted a teaching away from the ‘092 patent.

4. Patent Literature Should Not Be Common General Knowledge

   Citations 11 and 12, which are both patent literature, were cited by the requester of invalidation action as “common general knowledge” and were combined with Citation 5. Materion claimed that only textbooks or reference books could be considered as “common general knowledge” and patent literature did not fall into this category.

Intellectual Property Court’s Opinion

1. The court stated that Table 2 of Citation 5 already disclosed 9 kinds of silver-based alloy that could be used, which overlapped the claimed range of the ‘092 patent. As the two patents possessed the same problem to be solved, the same technical means and Claim 1 of the ‘092 patent did not produce an unexpected effect, a person skilled in the art would have the motivation to make reference to Citation 5 in order to achieve the ‘092 patent. The court declared that it was not necessary to conduct numerous trials to produce silver-indium alloys and silver-antimony alloys. Also, when making determination of a reasonable motivation to combine references, the factor of costs of materials or financial resources of a person skilled in the art should not be taken into account.
2. The ‘092 patent introduced a limitation to Claim 1 in a post-grant amendment: “said alloy is not silver-2.5atm% indium or silver-0.5atm% antimony”, to intentionally exclude certain values disclosed in Table 2 of Citation 5. However, Citation 5 disclosed that the amount of In or Sb was not limited and a person skilled in the art could select and adjust the amount of In or Sb to reach the desired technical solution to the problem. This exclusion in the post-grant amendment failed to overcome the prior art.
3. Citation 5 did not teach away from the ‘092 patent. A teaching away was defined as an indication of exclusion of the invention explicitly or implicitly recited in a citation. The prior art’s mere disclosure of a less preferred embodiment did not constitute a teaching away.
4. Patent literature could be a part of common general knowledge. Common general knowledge was defined as a fact known to one skilled in the art, which could be found in technical means made available to the public or information disclosed in a reference book or a textbook. Patent literature was not excluded to be considered as common general knowledge if it was generally known in the art.