G. R. No. 126627 – 409 SCRA 33 – Mercantile Law – Intellectual Property Law – Law on Patents – Doctrine of Equivalents – Function-Means-and-Result Test
Smith Kline is a US corporation licensed to do business in the Philippines. In 1981, a patent was issued to it for its invention entitled “Methods and Compositions for Producing Biphasic Parasiticide Activity Using Methyl 5 Propylthio-2-Benzimidazole Carbamate.” The invention is a means to fight off gastrointestinal parasites from various cattles and pet animals.
Tryco Pharma is a local corporation engaged in the same business as Smith Kline.
Smith Kline sued Tryco Pharma because the latter was selling a veterinary product called Impregon which contains a drug called Albendazole which fights off gastro-intestinal roundworms, lungworms, tapeworms and fluke infestation in carabaos, cattle and goats.
Smith Kline is claiming that Albendazole is covered by their patent because it is substantially the same as methyl 5 propylthio-2-benzimidazole carbamate since both of them are meant to combat worm or parasite infestation in animals. And that Albendazole is actually patented under Smith Kline in the US.
Tryco Pharma averred that nowhere in Smith Kline’s patent does it mention that Albendazole is present but even if it were, the same is “unpatentable”.
Smith Kline thus invoked the doctrine of equivalents, which implies that the two substances substantially do the same function in substantially the same way to achieve the same results, thereby making them truly identical for in spite of the fact that the word Albendazole does not appear in Tryco Pharma’s letters of patent, it has ably shown by evidence its sameness with methyl 5 propylthio-2-benzimidazole carbamate.
ISSUE: Whether or not there is patent infringement in this case
HELD: No. Smith Kline failed to prove that Albendazole is a compound inherent in the patented invention. Nowhere in the patent is the word Albendazole found. When the language of its claims is clear and distinct, the patentee is bound thereby and may not claim anything beyond them. Further, there was a separate patent for Albendazole given by the US which implies that Albendazole is indeed separate and distinct from the patented compound here.
A scrutiny of Smith Kline’s evidence fails to prove the substantial sameness of the patented compound and Albendazole. While both compounds have the effect of neutralizing parasites in animals, identity of result does not amount to infringement of patent unless Albendazole operates in substantially the same way or by substantially the same means as the patented compound, even though it performs the same function and achieves the same result. In other words, the principle or mode of operation must be the same or substantially the same.
The doctrine of equivalents thus 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.
