How to Avoid Losing Your Patent

During the early and mid-1990s, Purdue Pharma filed three patent applications for oxycodone formulations. The applications highlighted an unexpected finding:It has now been surprisingly discovered that the presently claimed controlled release oxycodone formulations acceptably control pain over a substantially narrower, approximately fourfold [range] (10 to 40 mg every 12 hour-around-the-clock dosing) in approximately 90% of patients. This is in sharp contrast to the approximately eight-fold range required for approximately 90% of patients for opioid analgesics in general.But in 2000, when Purdue sued Endo Pharmaceuticals, alleging that Endo's generic drug would infringe its three patents, Endo contended that the court should not enforce the patents because Purdue had not explained to the patent examiner that the discovery had been a product of an inventor's theory-based insight, unsupported by data. Federal district and appellate court judges inferred that Purdue had intended to deceive the patent examiner and declared Purdue's patents unenforceable. The result? The termination of rights in three patents that cover OxyContin, a drug that reportedly generated more than 70% of Purdue's annual revenue at one time.Such verdicts are known as findings of inequitable conduct. They can destroy or severely impair an inventor's reputation, says St. Jude Children's Research Hospital director of technology licensing J. Scott Elmer. "An inventor has a duty of candor, good faith, and honesty to patent examiners during the process of obtaining a patent," says David G. Latwesen, a patent attorney at Wells St. John in Spokane, Wash. Inequitable conduct can occur, he says, if an inventor intentionally misleads the examiner.And the penalties can go beyond a court determination: An inventor guilty of inequitable conduct can "probably forget about raising money or participating in a start-up company," says Elmer. Technology licensing personnel and patent attorneys, he says, will be extremely skeptical of any of the inventor's new inventions. The patent-killing behavior may also bring grave consequences for the inventor's organization if it holds the now-worthless patent rights.Want to avoid becoming the focus of an inequitable conduct defense? Here are eight tips from experts:1. Disclose Prior Art. In 1990, PerSeptive BioSystems filed a patent application for separating biological molecules using chromatography. The company apparently assured a patent examiner that its inventor had not created prior art by briefly discussing his invention during a public seminar, because he had not used a poster, abstract, or writing of any kind. Yet after Pharmacia Biotech alleged inequitable conduct during a patent infringement suit, a Massachusetts federal district court found in 1998 that the inventor had shown slides and had prepared an abstract distributed at the conference. Latwesen suggests that an inventor can best avoid inequitable conduct by disclosing anything that could impact a patent examiner's determination. There's no such thing as disclosing too much to your patent attorney or agent, says David Hricik, associate professor at Mercer University School of Law in Macon, Ga.2. Update the Examiner about Prior Art Discovered in Related Applications. An inventor may need to update the patent examiner if the inventor finds new information during patent prosecution, says Hricik. "Don't forget to call related applications to the examiner's attention," cautions Warren D. Woessner, of Schwegman, Lundberg, Woessner & Kluth in Minneapolis. Related US patent applications may be assigned to different patent examiners who discover prior art relevant to the other application. Patent attorney Joseph N. Hosteny also advises patent applicants to supply their US examiners with literature search results performed by examiners of counterpart patent applications filed outside the United States. At a minimum, he says, provide your US examiner with references cited against the novelty of the claimed invention.3. Don't Submit Partial Translations of Foreign References. When Semiconductor Energy Lab filed a patent application in 1995, they provided the patent examiner with an untranslated 29-page Japanese reference, a concise explanation of its relevance, and a one-page partial English translation. In 2000, the US Court of Appeals for the Federal Circuit concluded that untranslated portions of the reference contained information more relevant to Semiconductor's claimed invention than anything else considered by the patent examiner. "If foreign references are provided," Hosteny says, "translate them. Don't use partial translations."4. Update Examiners about Developments in Related Patent Litigation. While a patent application slowly winds its way through the examination process, a related patent may be the subject of litigation. In these situations, Hosteny suggests that patent applicants supply the patent examiner with prior art identified by the opposing party. Patent applicants may also need to update the examiner about any litigation decisions, he says. For example, a judge may decide that prior art narrows the scope of claims in the litigated patent, which may be similar to claims undergoing examination in the patent office. This happened in Mallinckrodt, Inc. v. Masimo Corp., a case about claims to a pulse oximeter decided by the Federal Circuit in September 2005. Masimo had not informed its patent examiner about a judge's decision that claims in a related patent must include certain limitations to avoid prior art.5. Disclose Data Even if it Undercuts Patentability Arguments. A 1988 Delaware federal district court decision revealed that Merck had informed a patent examiner that cyclobenzaprine did not cause drowsiness, even though the company had new data showing that this assertion was untrue. What should an inventor do if new data casts doubt about the invention? That depends, says W. Murray Spruill, a patent attorney at Alston & Bird of Raleigh, NC. Do the data merely show that the invention does not work quite as well as the inventor had hoped? Or, do the data contradict patentability arguments presented in the patent application or during patent prosecution? Mark J. Nuell, a patent attorney at Birch, Stewart, Kolasch & Birch in Falls Church, Va., says that if an inventor obtains new data that are contrary to a prior argument for patentability, then the inventor must submit the data for the patent examiner's consideration.6. Help Your Patent Representative to Identify Inventors. In the PerSeptive case, a judge decided that the company – with deceptive intent – had failed to include as co-inventors researchers from a business collaborator. "Applicants for US patents should do their best to name the correct inventors on an application," says Nuell. Unlike authorship of a scientific publication, inventorship is a legal determination. "The individuals involved in the project," Spruill says, "can aid their patent representatives by providing information about contributions to the claimed invention without any preconceived notion about who should be named as an inventor." The patent office allows patent applicants to correct honest mistakes about inventorship. A deliberate misrepresentation of inventorship is another matter. "Intentional omission of an inventor will result in an invalid patent," Nuell warns.7. Ensure that Affidavits Present the Truth. While fighting a rejection of patent claims to a glaucoma treatment, a Pharmacia inventor filed a declaration stating that a certain dose of a prior art compound does not significantly decrease intraocular pressure, a statement contradicted by an article that the inventor had co-authored. The declaration also reported a result from an experiment that the inventor had not performed. During patent prosecution, inventors may file an affidavit called a Rule 132 Declaration to support arguments against a rejection of patent claims. "Every sentence in such declarations," Woessner says, "should be examined to be sure it is the whole truth and nothing but the truth." In particular, inventors should not "provide data and represent it comes from an experiment if it does not," says Hosteny. Ruling that an Aventis inventor's misrepresentations in declarations supported a finding of inequitable conduct, a California federal district court judge declared one of the company's patents unenforceable.8. Don't Write Prophetic Examples in the Past Tense. When Cetus Corp. applied for a patent on Taq enzyme, the company included the detailed protocol used to purify the enzyme. "Fraction I was centrifuged for two hours at 35,000 rpm in a Beckman TI 45 rotor at 2 degrees C. and the collected supernatant was designated Fraction II," they wrote, for example. But it turned out that the inventors had never performed this and other work described in the patent, leading a federal district court judge in 2004 to find that the description of enzyme purification had been a prophetic example written in the past tense, and that Cetus had used purification "data" in the prophetic example to argue for patentability. This supported the judge's decision that courts should no longer enforce the Taq enzyme patent, which was one critical bit of intellectual property for PCR.While the above is an actual example, if an inventor writes a prophetic example in the past tense, a patent examiner will assume that it is an actual example and may give the patent application a more favorable and deferential examination than it merits. A court may decide that this represents a deliberate act of deception constituting inequitable conduct, Elmer warns.Final words of advice from Latwesen: "The route to obtaining a good patent is not to conceal pertinent information from the PTO, but rather is to provide all pertinent information to the PTO and show that the invention is patentable on its own merits."

How to Avoid Losing Your Patent

During the early and mid-1990s, Purdue Pharma filed three patent applications for oxycodone formulations.

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