SMITH KLEINE VS. CA

FACTS: Petitioner, the registered patent holder, filed a complaint for infringement of patent against private respondent alleging that private respondent appropriated for its drug Impregon, the active ingredient of Albendazole, which is substantially the same as Methyl 5 Propylthio-2-Benzimidazole Carbamate covered by petitioner's patent since both of them are meant to combat worm or parasite infestation in animals. Petitioner also pointed out that its application for a patent in the Philippine Patent Office on account of which it was granted Letters Patent was merely a divisional application of a prior application in the U.S. which granted a patent for Albendazole. Both the trial court and the CA held that the respondent was not liable for any infringement of the patent of petitioner in light of the latter's failure to show that Albendazole is the same as the compound subject of Letters Patent.

SC: Petitioner's evidence failed to show the substantial sameness of petitioner's patented compound and Albendazole. The identity of result does not amount to infringement of patent unless Albendazole operates in substantially the same way as the patented compound, even though it performs the same function or the same result.

The doctrine of equivalents provides that an infringement also takes place when a device appropriates a prior invention by incorporating its innovative concept and, although with some modification and change, performs substantially the same function in substantially the same way to achieve substantially the same result. It requires satisfaction of the function-means-and-result test, the patentee having the burden to show that all three components of such equivalency test are met.

Divisional Application only means is that petitioner's methyl 5 propylthio-2-benzimidazole Carbamate is an invention distinct from the other inventions claimed in the original application divided out, Albendazole being one of those other inventions. Otherwise, methyl 5 propylthio-2-benzimidazole carbamate would not have been the subject of a divisional application if a single patent could have been issued for it as well as Albendazole.