Federal Circuit Precedential

Holding:  Claim construction may be performed implicitly when interpreting inherent disclosure of a prior art reference if the interpretation establishes the scope and meaning of a claim.

Zeiss owns US Patent No. 7,400,704 directed to an X-ray imaging system that incorporates projection magnification.  Sigray filed a petition for IPR alleging that the claims of the ‘704 Patent are invalid as anticipated by a scientific article authored by Jorgensen.  The PTAB found the claims of the ‘704 to not be unpatentable, and Sigray appealed this decision.

Independent claim 1 of the ‘704 patent recites an x-ray imaging system that comprises a projection x-ray stage including an x-ray source generating diverging x-ray beam and an optical stage that includes a detector and a magnification lens.  The ‘704 Patent further claims that a magnification of the projection x-ray stage is between 1 and 10 times.  Projection magnification occurs when an x-ray beam diverges as it travels, causing the spacing between rays to increase beyond the sample before reaching the detector. This divergence results in an image larger than the original sample. The degree of magnification depends on the spatial relationship between the source, sample, and detector, which influences the extent of ray spread.

The Jorgensen reference describes a system that uses an x-ray source to generate an x-ray beam, which passes through a sample and is then received by a detector.  The system described in Jorgensen does not explicitly aim for magnification and tries to reduce concerns related to magnification by providing a large distance between the sample and the source and a short distance between the sample and the detector.  Jorgensen also describes a collimated x-ray beam.  Jorgensen explicitly discloses all of the limitations of claim 1 except for the projection magnification component, which Sigray argues is inherently disclosed.

A limitation is inherently disclosed when a prior art reference must necessarily include the unstated limitation.  Sigray argued that the collimator described in Jorgensen does not completely eliminate divergence of the x-rays, but merely reduces divergence and therefore must produce some magnification.  Therefore, the PTAB implicitly construed the limitation “between 1 and 10 times” magnification to exclude small divergence that results in projection magnification that is only slightly greater than 1. 

The PTAB stated that it was not engaging in claim construction when making its decision, but the Federal Circuit held that this statement was not dispositive in determining whether the claim construction was performed.  Instead, the Federal Circuit looked to the outcome of the PTAB’s analysis and reasoning to determine whether there was claim construction.  If the outcome of the PTAB’s analysis establishes the scope and meaning of the claim, then construction has occurred.

After reviewing the PTAB’s analysis, the Federal Circuit found that the PTAB practiced claim construction on the limitation “wherein a magnification of the projection x-ray stage is between 1 and 10 times.”  The PTAB stated that Sigray failed to show that the x-ray beam in Jorgensen diverged “enough” to result in projection magnification between 1 and 10 times.  Further, the PTAB’s analysis indicated that it recognized that there was at least a small amount of divergence that would have led to magnification. 

As an example, in the PTAB’s description of the term “collimated x-ray beam,” the PTAB recognized that collimation can minimize beam divergence but does not completely eliminate beam divergence.  The PTAB’s reliance on this evidence to find no inherent disclosure implies that the PTAB narrowed the “between 1 and 10 times” limitation to exclude magnification that is just barely greater than 1.  The PTAB relied on other evidence, such as expert testimony, that stated that Jorgensen taught an x-ray beam that greatly reduced divergence but did not completely eliminate divergence. 

The Federal Circuit found the PTAB’s implicit construction of the phrase “between 1 and 10 times” to exclude minor magnification just over 1 to be legal error.  The language of the claims governs the scope and meaning of the claims, unless intrinsic evidence requires a different conclusion.  Jorgensen’s x-ray beams have at least a minor amount of divergence and therefore must result in some magnification.  This minor magnification falls within the range of 1 and 10 times that is recited in claim 1.  Therefore, the Federal Circuit ruled that Jorgensen inherently discloses magnification, overturning the PTAB’s decision.