The New 'Material Effect' Test

In <i>Bayer AG v. Schein Pharm., Inc.</i>, 301 F.3d 1306 (Fed. Cir. 2002), the Federal Circuit articulated a new 'material effect' test for the best mode requirement. The court affirmed the validity of a patent covering the antibiotic drug ciprofloxacin on the grounds that it properly claimed priority to a parent application that satisfied the best mode requirement. With the priority date of the parent application, the patent was not invalidated under section 102(d) by an earlier filed foreign patent. The three-judge panel agreed that the parent application met the best mode requirement; however, the panel disagreed as to why the best mode requirement was satisfied. The majority reviewed the prior case law and found 'that the best mode of making and using the invention need be disclosed if it materially affects the properties of the claimed invention.' <i>Id.</i> at 1319-1320. Judge Radar concurred in the result, but strenuously objected to the creation of this additional criterion.

14 minute read October 02, 2003 at 11:16 PM
By
Otis Littlefield
The New 'Material Effect' Test

In Bayer AG v. Schein Pharm., Inc., 301 F.3d 1306 (Fed. Cir. 2002), the Federal Circuit articulated a new 'material effect' test for the best mode requirement.

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