IP Law Daily, PATENT—Fed. Cir.: Prosecution history precluded finding that chip testing equipment infringed patent under doctrine of equivalents, (Nov 5, 2013)

By Thomas Long, J.D.

Prosecution history estoppel precluded a manufacturer of semiconductor chip testing equipment from asserting that a competitor’s digital viewing system for testing equipment infringed its patent under the doctrine of equivalents, the U.S. Court of Appeals for the Federal Circuit has held (Integrated Technology Corp. v. Rudolph Technologies, Inc., November 4, 2013, Moore, K.). An award of treble damages based on a finding of willful infringement was vacated.

Patent-in-suit. Plaintiff Integrated Technology Corp. (“ITC”) owned U.S. Patent No. 6,118,894 (“the '894 patent”), which disclosed a digital viewing system used in inspection equipment for probe cards used to test chips on semiconductor wafers. Probe cards contained structures called probes; the tips of the probes made contact with bonding pads on the periphery of each chip. The probe tips first pierced the oxide layer atop the conductive layer of the bonding pad, and then the tips were moved along the pads to a second position to create a reliable electrical contact, leaving a “scrub mark” on the bonding pad in the process.

The patented viewing system was used to assess whether probes had become misaligned relative to each other by predicting the length and location of scrub marks. The system included a camera under a viewing window that obtained the three-dimensional coordinates of the probe tips in the first and second states.

Claim 1 of the '894 patent was representative of the asserted claims and stated “An integrated circuit probe card inspection system … comprising: … a window with a flat surface contacted by said probe tip, said viewing system obtaining said digital image through said window in a first state where said probe tip is driven in contact with said window with a first force, and in a second state where said probe tip is driven in contact with said window with a second force, said second force being different from said first force ….” (emphasis added).

Accused products. According to ITC, two categories of products made and sold by defendant Rudolph Technologies, Inc. (“Rudolph”) infringed the asserted claims: (1) products in which the probe tips made physical contact with the viewing window before, or at, the moment an image is taken (“pre-2007 products”); and (2) products that obtain a first image when the probe tips are approximately five microns above the viewing window (“no-touch products”). ITC alleged that the second category of products infringed under the doctrine of equivalents.

District court proceedings. The district court found Rudolph liable for infringing the '894 patent. The court granted summary judgment of literal infringement as to the pre-2007 products. After a jury trial on the remaining issues, the jury determined that the infringement of the pre-2007 products was not willful and awarded ITC lost profits of nearly $7.7 million. The jury found willful infringement by the no-touch products under the doctrine of equivalents and awarded lost profits of nearly $7.8 million.

Rudolph appealed the district court’s denial of its motion for judgment as a matter of law (JMOL) that prosecution history estoppel barred the application of the doctrine of equivalents. Rudolph also challenged the award of damages, the court’s determination that the case was “exceptional” for purposes of an attorneys’ fee award under 35 U.S.C. §285, and that Rudolph failed to prove laches.

Infringement under doctrine of equivalents. A patent applicant that surrenders subject matter during prosecution of an application is estopped from later recapturing that matter through the doctrine of equivalents. Prosecution history estoppel presumptively applies when the applicant has made a narrowing claim amendment related to patentability. The patentee may rebut the presumption by establishing that (1) the equivalent was unforeseeable at the time of the application; (2) the rationale underlying the amendment bore only a tangential relation to the asserted equivalent; or (3) there was some other reason that the patentee could not reasonably be expected to have described the equivalent.

Claim 1 of the '894 patent, as originally filed, recited “a window with a flat surface contacted by said probe tip.” The USPTO’s examiner rejected the original claim as indefinite under 35 U.S.C. §112, paragraph 2, and anticipated under §102(b) by U.S. Patent No. 4,757,256 (“Sato”). ITC amended the claim to also recite “in a first state where said probe tip is driven in contact with said window with a first force.”

The district court determined that ITC had not made a narrowing amendment because the original and issued claims both required contact between the plate and the probe tip. Therefore, in the district court’s view, the prosecution history did not preclude a finding of infringement by equivalence.

The Federal Circuit held that the amendment did narrow the scope of the original claim in response to patentability objections by the examiner and that, therefore, prosecution history estoppel presumptively applied. By its plain language, the amendment added a requirement that there must be two different forces that drive the probe tip in contact with the viewing window in two separate states.

The appellate court also held that ITC did not meet its burden of proving that an exception to prosecution history estoppel applied. First, ITC did not meet its burden under the “tangential relation” exception. A tangential rationale for the amendment was not objectively apparent from the prosecution history. Even if ITC did not need to surrender a lack of physical contact between the probe tip and window in either state to overcome Sato, the dispositive fact is that it had done so, the court said. ITC’s representations to the examiner indicated that it was relying on physical contact to overcome the prior art. The public was entitled to rely on these representations, according to the court.

Second, ITC did not prove that the equivalent was objectively unforeseeable. When a patentee originally claims the subject matter alleged to infringe but then narrows the claim in response to a rejection, the patentee may not argue that the surrendered territory comprised unforeseen subject matter. Moreover, the record did not indicate that the equivalent was the innovative aspect of Rudolph’s no-touch products.

Third, the court rejected ITC’s argument that literal infringement by the no-touch products was an alternative basis to affirm the judgment. Substantial evidence supported the jury’s determination that the no-touch products did not literally infringe.

Accordingly, the Federal Circuit concluded that ITC’s narrowing amendment during prosecution surrendered the equivalent from the scope of the asserted claims and that the application of the doctrine of equivalents was barred by prosecution history estoppel. Therefore, the court reversed the district court’s denial of Rudolph’s motion for JMOL that its accused no-touch products did not infringe under the doctrine of equivalents. Because the finding of willfulness was based on that finding of infringement, that determination also was reversed, and the corresponding award of treble damages was vacated.

Damages for literal infringement. The court reviewed the jury’s determination of the amount of damages for substantial evidence. Rudolph argued that the award of lost profits for literal infringement by the pre-2007 products should be vacated because the jury’s award was based on the erroneous premise that the no-touch products could not be noninfringing alternatives.

The Federal Circuit agreed with ITC that substantial evidence supported the jury’s award of lost profits for literal infringement. ITC had presented a two-supplier theory of lost profits that was independent of the existing of noninfringing alternatives. The damages award for literal infringement was upheld.

Exceptional case. The district court based its finding that the case was “exceptional” for purposes of the fee-shifting provision of §285, in part, on its erroneous finding that Rudolph had engaged in willful infringement. Accordingly, the Federal Circuit vacated the district court’s finding of an exceptional case and the corresponding award of attorneys’ fees.

Laches. The appellate court upheld the district court’s determination that Rudolph did not prove laches. There was no clear error in the district court’s finding that ITC had not unreasonably delayed filing suit. The finding of no laches was affirmed.

The case is Nos. 2013-1593 and 2013-1618.

Attorneys: Jay R. Campbell (Renner, Otto, Boisselle & Sklar, LLP) for Integrated Technology Corp. Daniel W. McDonald (Merchant & Gould P.C., of Minneapolis, Minnesota) for Rudolph Technologies, Inc.

Companies: Integrated Technology Corp.; Nevada Integrated Technology Corp.; Rudolph Technologies, Inc.; Mariner Acquisition Company, LLC

Cases: Patent FedCir