Ex parte Sobota, decided November 27, 2019. Ex parte Sobota PTAB Decision Claim 11 of US Patent Application No. 14/907,957, the subject of this appeal, recites:
11. A process for preparing trichlorosilane (TCS), comprising reacting metallurgical silicon (mg-Si) having a titanium content of 0.08 wt% to 0.12 wt.%, and a phosphorus content ≥ 30 ppmw with HCl.
The Examiner rejected the claims over a combination of Lobreyer and Kutsovsky, the primary reference acknowledged to lack a teaching of the presence of phosphorus, or an amount of titanium within the recited range. The secondary reference was alleged to cure these deficiencies with a teaching that “Metallurgical grade silicon contains impurities such as [insert list of 16 possible impurities, with associated ranges for each]” Emphasis added. See, paragraph  of Kutsovsky, attached. Kutsovsky
The Board was persuaded by Appellant’s arguments, reiterating them as follows:
Appellant emphasizes that Kutsovsky does not even mention all of the impurities known to exist in metallurgical grade silicon, nor do the ranges expressed correspond to the actual maximum or minimum ranges experienced in metallurgical grade silicon. Appellant argues that whether one might select out of all of the possible impurities and impurity ranges disclosed by Kutsovsky [the claimed amounts of titanium and phosphorus], one might just as easily select ranges of phosphorus and calcium, of boron and carbon, of oxygen and phosphorus, of magnesium and manganese…or any other of the numerous permutations and combinations cited by Kutsovsky and the amounts of these impurities.
And held “We are persuaded that the Examiner has not set forth a factual basis which is sufficient to support a prima facie case of obviousness. Citing In re Warner, 379 F.2d 1011, 1017 (CCPA 1967) (“A rejection based on section 103 clearly must rest on a factual basis, and these facts must be interpreted without hindsight reconstruction of the invention from the prior art”).