In one of it's last decisions of last month, the Board of Patent Appeals and Interferences reversed a Patent Examiner's 35 U.S.C. 103 obviousness rejection in response to the Applicant's arguments that the combination of the cited prior art would render the main reference inoperable. As a South Florida patent practitioner, the case of Ex parte Regini was interesting to me because it illustrated the burden an Examiner must meet when issuing a 103 obviousness rejection.
The case of Ex part Regini involved a chemical process for etching channels into a wafer used in fabricating a microprocessor. The claimed process recited the use of chemically reactive gas to etch the channels. The Patent Examiner rejected the claimed process using a combination of two prior art references - Vassalli (for etching) and Fong (for chemically reactive gas). The Applicant argued the Vassalli reference expressly stated that even when a small amount of chemically reactive gas is introduced, "the effectiveness of the technique has been lost." I.e., Applicant argued that combining Vassalli with Fong would render Vassalli inoperable - thereby rendering the combination improper. In other words, it couldn't possibly be obvious to combine two references if the combination would result in an inoperable result. The Patent Examiner did not respond to this argument and simply argued that it would have been obvious to combine Vassalli and Fong.
If a proposed modification would render the prior art invention being modified unsatisfactory for its intended purpose, then there is no suggestion or motivation to make the proposed modification. In re Gordon, 733 F.2d 900, 902 (Fed. Cir. 1984). Further, "a reference may be said to teach away when a person of ordinary skill, upon reading the reference, would be discouraged from following the path set out in the reference, or would be led in a direction divergent from the path that was taken by the applicant." In re Gurley, 27 F.3d 551, 553 (Fed. Cir. 1994).
In Ex part Regini, the Board found the Examiner "fails to respond to Appellants' teaching away argument. In this regard, the Examiner does not explain why it would have been obvious to employ Fong's plasma of inert gas and chlorine-containing gas, which are known to be chemically reactive, to remove a silicon native
oxide layer on Vassalli's wafer in view of Vassalli's teaching that 'the effectiveness of the technique has been lost' when 'even a small amount of chemically reactive gas' is introduced to its polycrystalline silicon, which is positioned above its wafer." Consequently, the Board reversed the Examiner's 103 rejection on the grounds that the combination of Vassalli and Fong was not proper.
What can we learn from this case? First, if a cited reference expressly teaches away from a certain combination, then you have grounds for reversing a 103 rejection asserting the combination - and you don't need outside evidence such as textbooks, 1.132 Affidavits or other patents to support your point. The express teaching-away language in the cited reference can be enough to get a reversal! Second, an Examiner is required to provide a reason why a combination is obvious in a 103 rejection, especially in response to an inoperability argument. If he does not provide such a reason, this is grounds for a reversal of the103 rejection.
