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CAFC-DCTJuly 31, 2026·25-1412·Affirmed summary judgment of noninfringement.

Regents of the University of Michigan v. Leica Microsystems, Inc.

District Court

Holding

The Federal Circuit affirmed, holding that the claimed “said supercontinuum white light pulse” refers back to a “supercontinuum white light pulse comprising an entire spectrum of white light.” Because the accused products used discrete, selected wavelengths filtered from a white-light pulse before reaching the sample, they did not meet the claim limitation under that construction.

Why It Matters

The decision underscores that antecedent-basis language, claim differentiation within the same claims, specification statements, and prosecution distinctions over filtered discrete wavelengths can collectively lock a patentee into a narrower infringement theory.

Full Summary

Regents of the University of Michigan v. Leica Microsystems, Inc. The Federal Circuit affirmed, holding that the claimed “said supercontinuum white light pulse” refers back to a “supercontinuum white light pulse comprising an entire spectrum of white light.” Because the accused products used discrete, selected wavelengths filtered from a white-light pulse before reaching the sample, they did not meet the claim limitation under that construction. The decision underscores that antecedent-basis language, claim differentiation within the same claims, specification statements, and prosecution distinctions over filtered discrete wavelengths can collectively lock a patentee into a narrower infringement theory. Affirmed summary judgment of noninfringement. The asserted independent claims required a “supercontinuum white light pulse comprising an entire spectrum of white light” that excites fluorophores in the sample. Michigan argued that the claims did not require the entire spectrum of white light to physically reach the sample; the Federal Circuit rejected that reading based on the plain claim language and the anaphoric effect of “said.” The court relied on claim language distinguishing the entire supercontinuum from a “portion” of the pulse, specification passages indicating the entire spectrum reaches the sample and rejecting filters, and prosecution statements distinguishing prior art that used discrete selected wavelengths. Because Michigan’s noninfringement appeal depended entirely on its proposed claim construction, the Federal Circuit affirmed once it adopted the district court’s construction. The court declined to review claim-construction issues not implicated by the judgment. claim construction infringement non-precedential claim construction infringement non-precedential claim construction infringement non-precedential

Key Points

  • The asserted independent claims required a “supercontinuum white light pulse comprising an entire spectrum of white light” that excites fluorophores in the sample.
  • Michigan argued that the claims did not require the entire spectrum of white light to physically reach the sample; the Federal Circuit rejected that reading based on the plain claim language and the anaphoric effect of “said.”
  • The court relied on claim language distinguishing the entire supercontinuum from a “portion” of the pulse, specification passages indicating the entire spectrum reaches the sample and rejecting filters, and prosecution statements distinguishing prior art that used discrete selected wavelengths.
  • Because Michigan’s noninfringement appeal depended entirely on its proposed claim construction, the Federal Circuit affirmed once it adopted the district court’s construction.
  • The court declined to review claim-construction issues not implicated by the judgment.
claim constructioninfringementnon-precedential

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