WASHINGTON _ At first glance, dye manufacturing andbiotechnology appear to have little in common. But the same lawsprotect the proprietary methods developed by members of bothindustries. On Tuesday, the U.S. Supreme Court heard oralarguments in a patent infringement case that could have wide rangingeffects for the biotechnology community.

At issue in Warner-Jenkinson Co. Inc. vs. Hilton Davis Chemical Co.was "the doctrine of equivalents" a premise in the law that a productcan infringe upon an existing patent if it differs in an insubstantialway from the literal claims written into the patent.

"Without the doctrine of equivalents, many biotechnology patentswould have no value," said David Schmickel, patent and legalcounsel for the Biotechnology Industry Organization (BIO) whichfiled a brief in the case.

The specifics of the case involved a proprietary process forseparating dyes. Hilton Davis had developed a process that wassignificantly different from prior methods because it separated thedyes at a pH of six, substantially lower than previously knownmethods that used pH above nine. The company was given a patentthat specified a pH range between six and nine. The patent officerchose a limit of nine because that was pH used in the "prior art," butchose the lower limit based on the fact that it was the pH theirmethod used.

Warner-Jenkinson extended the process to a pH of five and HiltonDavis claimed patent infringement based upon the doctrine ofequivalents _ that a pH of five was not substantially different frompH six. The Federal Circuit Court and the U.S. Court of Appealsagreed with Hilton Davis and Warner Jenkinson appealed to theSupreme Court.

After a rocky start, when Chief Justice William Rehnquist askedWarner-Jenkinson attorney Richard Taranto to define pH, Tarantoproffered the argument that although the doctrine of equivalents is animportant legal concept, it did not apply to this particular case.

And The Biotech Connection Is . . .

Maintaining the power of the doctrine of equivalents holds particularimportance for the biotechnology industry. In its amicus _ friend ofthe court _ brief, BIO pointed to the issue of the codons on a sectionof DNA that codes for a protein. Because the genetic code uses threenucleotides _ a codon _ to encode for an amino acid, there are 64potential codons. Three of these codons are termination sequences.That leaves 61 codons for the 20 amino acids. As a result, eachamino acid has more than one codon.

"As a policy decision you don't want a patent applicant to list the50,000 different nucleotide sequences that can encode a singleprotein, but you want to offer some patent protection," Schmickelsaid. "Everyone will recognize that if you could just change a singlebase and have that DNA molecule encode the same protein thatwould make the patent worthless."

Because patent officers will often limit a DNA patent to a singlenucleotide sequence, without the doctrine of equivalents the patentapplicant would only be protected for the single species of the DNAwhich encodes a protein "which would be a disaster for anyone whohas a gene patent," Schmickel said.

Because both the petitioner and the respondent in the case hold thatthe doctrine of equivalents is important to patent law, it is unlikelythat the court will decide to overturn the doctrine. However, the courtwill make that decision sometime before July 1997. n

-- Lisa Seachrist Washington Editor

(c) 1997 American Health Consultants. All rights reserved.