“Obvious to Try” Doctrine (In re Kubin)

The Federal Circuit relied upon the “obvious to try” doctrine to uphold a USPTO ruling that a patent applicant’s DNA molecules encoding a protein known as ‘NAIL’ were obvious over the combined prior art references.  The Federal Circuite stated that “obvious to try” is erroneously equated to obviousness if (1) the inventor is faced with “numerous possible choices … where the prior art gave either no indication of which parameters were critical or no direction as to which of many possible choices is likely to be successful” or (2) “the prior art gave only general guidance as to the particular form of the claimed invention or how to achieve it.”  The Federal Circuit ruled in the Kubin case that a skilled artisan would have had a “reasonable expectation of success” in obtaining the claimed invention in light of the prior art.  The Federal Circuit further declined to adopt any “formalistic rules” with respect to whether prior art is predictable or unpredictable.  In re Kubin 08-11843