- Shenzhen Root Technology Co., Ltd. v. Willow Blossom Holdco Limited And Willow Innovations, Inc.All claims unpatentablePTAB · Sep 25, 2026 · IPR2025-00554 · APJ Barry L Grossman · IPR · Final written decision
Claims 17–19 and 21–33 are unpatentable as obvious under each asserted § 103 ground.
RulingsFinal written decision- Skill levelSkill level petitioner adoptedDecided for petitioner
“Factors pertinent to a determination of the level of ordinary skill in the art include: (1) educational level of the inventor; (2) type of problems encountered in the art; (3) prior art solutions to those problems; (4) rapidity with which innovations are made; (5) sophistication of the technology; and (6) educational level of workers active in the field. Env’t Designs, Ltd. v. Union Oil Co., 713 F.2d 693, 696–697 (Fed. Cir. 1983) (citing Orthopedic Equip. Co. v. All Orthopedic Appliances, Inc., 707 F.2d 1376, 1381–82 (Fed. Cir. 1983)). Not all such factors may be present in every case, and one or more of these or other factors may predominate in a particular case. Id. Moreover, these factors are not exhaustive but are merely a guide to determining the level of ordinary skill in the art. Daiichi Sankyo Co. v. Apotex, Inc., 501 F.3d 1254, 1256 (Fed. Cir. 2007). In determining a level of ordinary skill, we also may look to the prior art, which may reflect an appropriate skill level. Okajima, 261 F.3d at 1355.” slip op. at 17
- Claim Construction › Threshold & procedure › Whether a term needs construction (O2 Micro)No construction neededOther
“according to the Phillips standard,” and that “no formal claim constructions are necessary for purposes of resolving controversies in this proceeding. Pet. 3. We agree. Given the lack of dispute on this record, we do not perceive the need to construe any claim limitation. Claims must be construed “only to the extent necessary to resolve the controversy.” AstraZeneca AB v. Mylan Pharms. Inc., 19 F.4th 1325, 1345 (Fed. Cir. 2021) (quoting Vivid Techs., Inc. v. American Science & Eng’g, Inc., 200 F.3d 795, 803 (Fed. Cir. 1999); see also Nidec Motor Corp. v. Zhongshan Broad Ocean Motor Co., 868 F.3d 1013, 1017 (Fed. Cir. 2017) (“Because we need only construe terms ‘that are in controversy, and only to the extent necessary to resolve the controversy,’ we need not construe the claim preambles here where the construction is not ‘material to the [obviousness] dispute.’” (citations omitted)).” slip op. at 18
- Expert testimonyPetitioner expert creditedDecided for petitioner
“We find Mr. Bauer’s testimonial evidence persuasive and undisputed as to why a person of ordinary skill, a degreed engineer with two years of experience designing human breast pump equipment, would modify Furrer to use a battery as a power source, and have a reasonable degree of confidence that it would work successfully.” slip op. at 26
- Obviousness (§103) › Motivation to combine / reasonable expectation of successMotivation foundReasonable expectation foundDecided for petitioner
“We find Mr. Bauer’s testimonial evidence persuasive and undisputed as to why a person of ordinary skill, a degreed engineer with two years of experience designing human breast pump equipment, would modify Furrer to use a battery as a power source, and have a reasonable degree of confidence that it would work successfully. Concerning the proposed combination of Furrer and Alvarez, Mr. Bauer testifies why a person of ordinary skill would combine Furrer and Alvarez, explaining that: a POSITA6 would have turned to the teachings of Alvarez to implement Furrer’s vacuum pump using a conventional pump controller having a portable, battery-powered pump to not only increase portability and to allow the user to move about when using the device but also to provide improved control for the system. Ex. 1003 ¶ 138. Mr. Bauer also testifies: a POSITA would have recognized that Alvarez advantageously provides details for such a conventional vacuum pump suitable for safely and controllably delivering negative pressure using a “[c]ontroller 115 [that] “houses the power source and drive mechanism for pumping device 100, and also contains hardware for various functions, such as controlling pumping device 100, milk production quantification, and communication with other devices. 6 “POSITA” is a patent law acronym for a “person of ordinary skill in the art.” Id. ¶ 139 (citing Ex. 1005 ¶ 69). Mr. Bauer further explains that Alvarez discloses that a “pump unit2100 [disclosed in Alvarez] preferably include[es] a controller and processor 2104 as well as a motor 2102 for actuating the device.” Id. (citing Ex. 1005 ¶ 115); see also id. ¶¶ 140–142 (providing “second,” “third,” and “fourth” reasons why a person of ordinary skill would have been motivated to combine Furrer and Alvarez). Mr. Bauer concludes from his analysis that “a person skilled in the art” slip op. at 26
Patent outcomesUS 11,806,454 unpatentableClaim construction§ 103 obviousnesscites Phillips · KSR · GrahamPatents in suitUS 11,806,454 - Charles River Laboratories, Inc. v. Seikagaku CorporationAll claims unpatentablePTAB · Sep 8, 2026 · PGR2025-00023 · APJ Per Curiam · PGR · Final written decision
Claims 1–9 are unpatentable as anticipated by the ’629 publication; the claims are not entitled to the 2013 priority date.
RulingsFinal written decision- Skill levelSkill level board ownOther
“We find that a rigid requirement as to the subject of a POSITA’s doctoral degree (e.g., biochemical engineering, enzymology), or experience working specifically with horseshoe crab proteins, is not consistent with the evidence of record. See, e.g., Ex. 1067, 20:23–21:2 (Dr. Schaefer testifying that the fact the “name of [his] Ph.D. is immunology . . . does not change the fact that the core of [his] thesis training was really in molecular biology”), 22:3–15 (explaining that “the fact that the production of proteins recombinantly is mostly species agnostic”); Ex. 1069, 45:20–47:17 (Dr. Morris testifying that whether a person is a POSITA depends on the person’s “experience, [ ] publications,” and work done for the Ph.D. rather than the name of the Ph.D. program). We also find that evidence of record supports Petitioner’s assertion that, for purposes of defining a POSITA, “[m]ore education could substitute for experience, and vice versa.” See, e.g., Pet. 22; Ex. 1065, 99:14–100:3. Accordingly, based on the entirety of the trial record, we find a POSITA with respect to the claims of the ’109 patent would have had a two years of experience with cloning genes, expressing cloned genes as proteins, and/or characterizing such cloned genes and proteins, with more education being able to substitute for experience, and vice versa. A POSITA may also have collaborated with others, including those with specific experience in utilizing or assessing horseshoe crab Factor C for endotoxin detection and quantitation.” slip op. at 9
- Claim Construction › Threshold & procedure › Whether a term needs construction (O2 Micro)No construction neededOther
“Neither party proposes an express construction of any claim term. See Pet. 22–23 (not proposing any constructions); PO Resp. 23 (“Patent Owner agrees that the terms can be afforded their plain and ordinary meaning.”). However, Patent Owner states that some of Petitioner’s arguments implicitly construe claim 1 in an erroneous manner. PO Resp. 23–28. “For example, Petitioner argues that ‘an adequate written description would have to either disclose representative examples of the possible working cascades of various proteins or some accurate structural feature of the claimed proteins that allow them to function in the claimed assay as a whole.’” Id. at 23 (quoting Pet. 35). Patent Owner argues that, contrary to what Petitioner’s argument allegedly implies, “Claim 1 is directed to a method for producing an endotoxin assay agent” and does not require the use – Owner that claim 1 does not require the use of endotoxin assay agent. However, the claimed endotoxin assay agent must be capable of performing the assay, as counsel for Patent Owner acknowledged. Tr. 83:5–9.” slip op. at 10
- BurdenNot shown unpatentable
“In this case, to show that the claims of the ’109 patent are unpatentable for lack of written description, Petitioner would have needed to show that the specification as filed (i.e., the ’420 application) fails to reasonably convey to those skilled in the art that Patent Owner had possession of the claimed subject matter as of the July 3, 2023, filing date. Petitioner did not. Pet. 23–24. Nor does Petitioner’s declarant offer testimony that could support such a showing. See Ex. 1003 ¶50 (“I have been asked to provide my opinions as to the state of the art in this field for purposes of determining what the inventors disclosed as their invention as of December 10, 2013.”), ¶51 (“Whenever I offer an opinion in this declaration about the knowledge of a POSA, the manner in which a POSA would have understood the claims of the ’109 patent or its description, the manner in have been led to do based on the prior art, I am referencing the December 10, 2013 timeframe.”). In our Institution Decision, we stated: Although the ’420 application is essentially identical to the ’767 application, the person of ordinary skill in 2013 is not the same as in 2023. See Ariad, 598 F.3d at 1351 (“[T]he [written description] test requires an objective inquiry into the four corners of the specification from the perspective of a person of ordinary skill in the art.” (emphasis added)). Thus, the information presented in the Petition, which is limited to the perspective of a 2013 POSITA, does not demonstrate that it is more likely than not that at least 1 of the claims challenged in the Petition is unpatentable for lack of written description. Inst. Dec. 12 (alterations in original). During trial, Petitioner did not present any further arguments in support of Ground 1. See generally Pet. Reply. Petitioner has failed to prove that claims 1–9 are unpatentable for failing to meet the written description requirement set forth in 35 U.S.C. § 112(a).” slip op. at 12
- Disclosure Requirements (§112) › Written description (Ariad)Written description inadequateNot shown unpatentable
“Although the evidence before us shows that, in 2013, a POSITA knew how to recombinantly express genes in expression systems such as CHO or HEK-293 cell lines, the evidence shows that this was true only for genes whose genetic sequences were known or readily available. See, e.g., Ex. 1069, 34:11–22 (“Q. Okay. So you would agree that the creation of the recombinant protein requires the underlying sequence of, as you said, the original animal? A. Of course.”) Because it is undisputed that, in 2013, the genetic sequence for Limulus polyphemus Factor C was unknown, or least not publicly available, Falko-Gunter does not support a finding of adequate written description here. See, e.g., Tr. 48:18–19 (“Patent Owner agrees that there had not been, as of 2013, the full length cDNA sequence for Limulus polyphemus Factor C published.”).” slip op. at 23
Patent outcomesUS 11,959,109 unpatentableClaim construction§ 102 anticipation§ 112 disclosurePatents in suitUS 11,959,109 - Embody, Inc. / Zimmer Biomet Holdings, Inc. v. Lifenet HealthSome claims unpatentablePTAB · Aug 4, 2026 · IPR2025-00249 · APJ Michael J Fitzpatrick · IPR · Final written decision
Claims 1 and 4–8 are unpatentable: claims 1 and 4–6 as obvious over Huang2 and Kuo, and claims 7–8 as anticipated by Huang2; claims 2–3 were not shown unpatentable.
RulingsFinal written decision- Skill levelSkill level petitioner adoptedDecided for patent owner
“(“POSITA”) “would be a Ph.D. student with a minimum of two years of experience in their faculty advisor’s laboratory” and would have an understanding of “electrospinning fibers, including for tissue engineering, tissue engineering techniques, and using/performing FFT analysis.” Pet. 20– 21 (citing Ex. 1003 § II.C7). Patent Owner does not dispute Petitioner’s proposal but specifies the set of disciplines within which the Ph.D. would have been earned, namely “bioengineering, chemical engineering, mechanical engineering, or a related engineering discipline.” PO Resp. 6. We adopt and apply Petitioner’s proposal as clarified by Patent Owner regarding the Ph.D. discipline.” slip op. at 7
- Claim Construction › Intrinsic evidence (Phillips canons) › Lexicography (patentee as own lexicographer)Term construed board ownDecided for patent owner
“At the outset, we agree with Patent Owner that the Specification purports to define “major peaks” in the following sentence: “The ‘major peaks’ herein refer to peaks higher than the average of the peaks in the result.” Ex. 1001, 13:28–29. We determine that this language satisfies at least two of the criteria set forth in Alnylam. Specifically, the sentence at “refers to” to explain what qualifies as major peaks. That is not the end of the inquiry, however, as we find there is still some ambiguity as to whether the patentee intended to define “major peaks” so as to require so-called “minor peaks” in the claimed invention. See Bell Atlantic, 262 F.3d at 1268 (“[T]he intrinsic evidence must ‘clearly set forth’ or ‘clearly redefine’ a claim term so as to put one reasonably skilled in the art on notice that the patentee intended to so redefine the claim term.”). Importantly, the Specification does not treat the existence of minor peaks as prerequisites for the existence of major peaks. Indeed, the Specification does not discuss “minor peaks” at all. See generally Ex. 1001. Likewise, none of the claims of the ’227 patent, whether challenged or unchallenged, recites “minor peaks” or any additional peaks beyond the disputed “major peaks.” Id. at 23:30–24:42. Nor does the Specification include an example of FFT analysis results in which the average of the peaks therein is calculated and those higher than the average are identified as major peaks.8” slip op. at 9
- Obviousness (§103) › Motivation to combine / reasonable expectation of successMotivation foundMixed
“Petitioner has the better position. Huang2 teaches crosslinking and provides a reason for doing so (stability). In particular, Huang2 states: “To better mimic skin ECM, electrospun collagen fibers have been fabricated, however, the rapid degradation and poor mechanical properties determine that either crosslinking or combination with other materials is necessary to obtain a stable scaffold.” Ex. 1005, 1791 (emphasis added). It is true that, in describing work actually carried out, Huang2 states that blending with PCL was performed and does not mention crosslinking. See id. at 1792 (“Nanofibrous matrices of PCL and Collagen at a weight ratio of 3:1 were fabricated using electrospinning as previously described.”). However, the prior art – here, Huang2 – is not limited to that which it describes having created. See In re Mills, 470 F.2d 649, 651 (C.C.P.A. 1972) (“a reference is not limited to the disclosure of specific working examples”); see also In re Lemelson, 397 F.2d 1006, 1009 (CCPA 1968) (“The use of patents as references is not limited to what the patentees describe as their own inventions or to the problems with which they are concerned. They are part of the literature of the art, relevant for all they contain.”); In re Fritch, 972 F.2d 1260, 1264 (Fed. Cir. 1992) (“It is well settled that a prior art reference is relevant for all that it teaches to those of ordinary skill in the art.”). Huang2 teaches two stabilization methods when using collagen in scaffolds. Huang2 states that one or the other “is necessary to obtain a stable scaffold” (when using collagen), but it does not preclude or teach away from using Patent Owner-cited testimony of Dr. Mikos is not as definitive as Patent Owner suggests; Dr. Mikos’s testimony is that a person of ordinary skill in the art “typically would not have done both.” Ex. 2015 ¶64 (emphasis added). The bottom line is that Huang2 teaches the person of ordinary skill in the art two ways to stabilize scaffolds/matrices comprised of collagen, provides a reason for doing so (stability), and does not teach away from using both. We are persuaded that a “scaffold comprising crosslinked fibers comprising collagen” would have been obvious in view of the cited teachings of Huang2.” slip op. at 33
- Obviousness (§103) › Graham factors (scope of art, differences, level of skill)Not shown unpatentableNot shown unpatentable
“We are not persuaded by Appellant’s citations to either reference. As discussed above, Petitioner’s Ground 1 is premised on a person of ordinary skill in the art altering the native flat sheet structure of Huang2 by rolling it into a jelly-roll structure as taught by Kuo. See Pet. 41 (Beginning its claim 2 arguments with the following: “Claim 1 is obvious for the reasons expressed above in § X.A., supra, which are incorporated herein.”); see also Pet. Reply 17 (“[B]ased on the explicit teaching of Kuo, a POSA would have been motivated to take the electrospun flat scaffold made by the techniques of Huang2, seed it with the desired cells, and roll it to treat a tendon and ligament.” (emphasis added)). Indeed, the paragraphs of Kuo that Petitioner cites for disclosing “scaffold sheets,” explicitly describe rolling them into jelly-roll like structures. See Ex. 1018 ¶7 (stating that “the sheet is spirally contacting a scaffold sheet of fibrous material with a cell; and rolling the scaffold sheet in a jelly-roll like manner to form a spirally wound tissue construct”), ¶22 (describing a method comprising “forming a tissue construct by contacting a scaffold sheet of fibrous material with a cell; and rolling the scaffold sheet in a jelly-roll like manner to form a spirally wound tissue construct” and implanting it in a patient). Petitioner fails to argue that that “one or more elongated sheets” recited in claim 2 would encompass the rolled structure of its proposed modification. Nor does Petitioner articulate a claim construction argument that could support such an argument. Petitioner has failed to prove, by a preponderance of the evidence, that claim 2 would have been obvious over Huang2 and Kuo.” slip op. at 42
Patent outcomesUS 11,318,227 mixedClaim construction§ 102 anticipation§ 103 obviousnesscites Phillips · Markman · KSRPatents in suitUS 11,318,227 - Shenzhen Root Technology Co., Ltd. v. Willow Blossom Holdco LimitedAll claims unpatentablePTAB · Jul 30, 2026 · IPR2025-00560 · APJ Barry L Grossman · IPR · Final written decision
Claims 1–29 are unpatentable under each asserted obviousness ground, including Chang and Fang, because Petitioner proved unpatentability by a preponderance of the evidence.
RulingsFinal written decision- Expert testimonyPetitioner expert creditedDecided for petitioner
“Additionally, we note that Patent Owner did not cross-examine Mr. Ryan Bauer, who provided a detailed, 169-page expert report providing, on behalf of Petitioner, his opinions about the issues in this proceeding. See Exhibit 1003. Mr. Bauer’s testimonial evidence in this proceeding remains unrebutted.” slip op. at 3
- Skill levelSkill level petitioner adoptedDecided for petitioner
“Petitioner asserts that a person of ordinary skill in the art would have had “bachelor’s degree in mechanical engineering or a similar field and at least two years of experience designing human breast pump equipment. More education could substitute for experience and vice versa.” Pet. 8 (citing Ex. 1003 ¶¶ 15–18). Mr. Bauer’s Declaration testimony states he considered some of the factors listed above. Ex. 1003 ¶ 17. Mr. Bauer testifies that based on his background and experience, in his opinion, the level of ordinary skill is as stated by Petitioner. Id. at 18. Based on the prior art, the sophistication of the disclosed technology in the ’381 patent, and Mr. Bauer’s undisputed testimony, we adopt Petitioner’s definition of the level of ordinary skill.” slip op. at 17
- Claim Construction › Threshold & procedure › Whether a term needs construction (O2 Micro)No construction neededOther
“Petitioner asserts that the Examiner construed the term “self- contained, in-bra wearable device” to mean “complete, or having all that is needed, in itself’ and is capable of being worn in a bra.” Pet. 8 (citing Ex. 1005, 2290).14 According to Petitioner, “[Patent Owner] did not dispute this construction, and Petitioner applies it herein.” Id. Petitioner contends that all other terms “should receive their plain and ordinary meaning.” Id. We do not perceive the need to construe any claim limitation. Claims must be construed “only to the extent necessary to resolve the controversy.” AstraZeneca AB v. Mylan Pharms. Inc., 19 F.4th 1325, 1345 (Fed. Cir. 2021) (quoting Vivid Techs., Inc. v. American Science & Eng’g, Inc., 200 F.3d 795, 803 (Fed. Cir. 1999); see also Nidec Motor Corp. v. Zhongshan Broad Ocean Motor Co., 868 F.3d 1013, 1017 (Fed. Cir. 2017) (“Because we need only construe terms ‘that are in controversy, and only to the extent necessary to resolve the controversy,’ we need not construe the claim preambles here where the construction is not ‘material to the [obviousness] dispute.’” (citations omitted)).” slip op. at 17
- Obviousness (§103) › Motivation to combine / reasonable expectation of successMotivation foundReasonable expectation foundUnpatentable
“(3) 1[a][1] a diaphragm configured to prevent milk from reaching an air pump by forming a seal around its outer edge; Petitioner relies on Fang for the disclosure of a diaphragm, as stated in this clause. Pet. 25–26. Petitioner asserts the proposed combination of elements suggest a breast pump device that would have used a diaphragm pump including first and second diaphragm housing components and an elastic diaphragm, “in accordance with Fang’s suggestions.” Id. at 25. As also asserted by Petitioner, Fang discloses that flexible diaphragm 7 (i.e., a membrane) is configured to prevent milk from reaching the pump. Id. at 26 (citing Ex. 1009 ¶ 19 (“The elastic diaphragm 7 is used to prevent milk from flowing into the air pump main unit 8.”). Mr. Bauer testifies: The flexible diaphragm [diaphragm 7 in Fang] forms a watertight and airtight seal around its outer edge. In doing so, the diaphragm prevents the passage of milk from reaching the air pump and facilitates generation of negative pressure during operation. Fang also explains that the elastic diaphragm 7 deforms away from the nipple tunnel when a vacuum is created on a pumping chamber, which then creates negative air pressure in the nipple tunnel when a vacuum is created on a pumping chamber.” slip op. at 28
Patent outcomesUS 11,813,381 unpatentableClaim construction§ 103 obviousnesscites Phillips · KSR · GrahamPatents in suitUS 11,813,381 - Samsung Display Co., Ltd. v. Pictiva Displays International Ltd.All claims unpatentablePTAB · Jul 22, 2026 · IPR2024-01095 · APJ Garth D Baer · IPR · Remand
On remand, the Board maintained its finding that claims 2 and 17 are unpatentable under §103 over Diekmann and Ma, and Suzuki and Ma.
RulingsRemand decision- RemandDecided for petitioner
“that is both n-doped and comprised of 8-hydroxy-quinolinolato-lithium (Liq). The district-court defendant’s first invalidity challenge relied primarily on Clix2, which lacked an n-doped ETL. Paper 48, 2, Paper 50, 3. Thus, the asserted combination required modifying Clix2’s non-doped ETL by adding an n-dopant. Clix2’s missing n-doped ETL appeared to be a focus at trial. See Ex. 2034, 917:1–18, 920:8–14. Here, in contrast, Petitioner proposed a more modest modification to materially different primary references, Suzuki and Diekmann, which both already have n-doped ETLs. See Paper 50, 2–3; Paper 54 8–9. As we explained in our Final Written Decision, because Patent Owner did not contest that Liq acts as an n-dopant in Ma, Petitioner’s combinations were obvious because they merely “substitute one known n-dopant for another to further the same goal of improving ETL conductivity.” Paper 54, 12. That simple-substitution analysis would not be the same when n-doping Clix2’s non-doped ETL. For this reason, we agree with Petitioner that the district-court Clix2-based combination “is a different combination with a materially different motivation-to-combine analysis,” as compared to the Diekmann/Suzuki and Ma combinations that are at issue here. Paper 50, 3.” slip op. at 2
- Obviousness (§103) › Motivation to combine / reasonable expectation of successUnpatentableMotivation foundUnpatentable
“Dependent claims 2 and 17 require an electron transport layer (ETL) that is both n-doped and comprised of 8-hydroxy-quinolinolato-lithium (Liq). The district-court defendant’s first invalidity challenge relied primarily on Clix2, which lacked an n-doped ETL. Paper 48, 2, Paper 50, 3. Thus, the asserted combination required modifying Clix2’s non-doped ETL by adding an n-dopant. Clix2’s missing n-doped ETL appeared to be a focus at trial. See Ex. 2034, 917:1–18, 920:8–14. Here, in contrast, Petitioner proposed a more modest modification to materially different primary references, Suzuki and Diekmann, which both already have n-doped ETLs. See Paper 50, 2–3; Paper 54 8–9. As we explained in our Final Written Decision, because Patent Owner did not contest that Liq acts as an n-dopant in Ma, Petitioner’s combinations were obvious because they merely “substitute one known n-dopant for another to further the same goal of improving ETL conductivity.” Paper 54, 12. That simple-substitution analysis would not be the same when n-doping Clix2’s non-doped ETL. For this reason, we agree with Petitioner that the district-court Clix2-based combination “is a different combination with a materially different motivation-to-combine analysis,” as compared to the Diekmann/Suzuki and Ma combinations that are at issue here. Paper 50, 3.” slip op. at 2
- Obviousness (§103) › Graham factors (scope of art, differences, level of skill)UnpatentableUnpatentable
“that is both n-doped and comprised of 8-hydroxy-quinolinolato-lithium (Liq). The district-court defendant’s first invalidity challenge relied primarily on Clix2, which lacked an n-doped ETL. Paper 48, 2, Paper 50, 3. Thus, the asserted combination required modifying Clix2’s non-doped ETL by adding an n-dopant. Clix2’s missing n-doped ETL appeared to be a focus at trial. See Ex. 2034, 917:1–18, 920:8–14. Here, in contrast, Petitioner proposed a more modest modification to materially different primary references, Suzuki and Diekmann, which both already have n-doped ETLs. See Paper 50, 2–3; Paper 54 8–9. As we explained in our Final Written Decision, because Patent Owner did not contest that Liq acts as an n-dopant in Ma, Petitioner’s combinations were obvious because they merely “substitute one known n-dopant for another to further the same goal of improving ETL conductivity.” Paper 54, 12. That simple-substitution analysis would not be the same when n-doping Clix2’s non-doped ETL. For this reason, we agree with Petitioner that the district-court Clix2-based combination “is a different combination with a materially different motivation-to-combine analysis,” as compared to the Diekmann/Suzuki and Ma combinations that are at issue here. Paper 50, 3.” slip op. at 2
Patent outcomesUS 11,828,425 unpatentable§ 103 obviousnessPatents in suitUS 11,828,425 - Runergy Alabama Inc. / Runergy USA Inc. et al. v. Trina Solar Co., Ltd.All claims unpatentablePTAB · Apr 15, 2026 · IPR2025-00187 · APJ Debra L Dennett · IPR · Final written decision
Claims 1–17 are unpatentable under § 103, principally because Chang in view of Jin renders them obvious; the Jin/Feldmann grounds were not shown.
RulingsFinal written decision- Skill levelSkill level petitioner adoptedDecided for petitioner
“Petitioner contends that a person of ordinary skill in the art would have been someone with an advanced degree involving the disciplines of electrical engineering, applied physics, chemistry, or materials science, and at least two years of experience designing, developing, or researching in the field. Alternatively, that person would have had a bachelor’s degree in electrical engineering, applied physics, or materials science, and at least three years of experience designing, developing, or researching in the field. Pet. 4 (citing Ex. 1003 ¶ 49).” slip op. at 10
- Claim Construction › Threshold & procedure › Whether a term needs construction (O2 Micro)No construction neededOther
“Petitioner contends that “[n]o claim construction is believed to be necessary to resolve this Petition.” Pet. 24. Patent Owner does not address claim construction. See generally Resp.; Sur-reply. For purposes of this Decision, we need not expressly construe any claim terms. See Vivid Techs., Inc. v. Am. Sci. & Eng’g, Inc., 200 F.3d 795, 803 (Fed. Cir. 1999) (holding that “only those terms need be construed that are in controversy, and only to the extent necessary to resolve the controversy”); see also Nidec Motor Corp. v. Zhongshan Broad Ocean Motor Co., 868 F.3d 1013, 1017 (Fed. Cir. 2017) (citing Vivid Techs. in the context of an inter partes review).” slip op. at 11
- Expert testimonyPatent owner expert creditedDecided for patent owner
“gap-T isolation region would prevent shorting and that extending the tunnel oxide layer the edge “could trap impurities and create negative fixed oxide charges, which could then create a p-type inversion in the n-type base substrate, leading to a leakage path to the p-type emitter on the front of the solar cell” (Ex. 1003 ¶ 116 (emphasis added)) but are not convinced by his equivocal testimony. Notably too, neither Jin nor Feldmann discuss issues relating to trapped impurities and Petitioner, as well as Dr. Banerjee, fail to direct our attention to any record evidence to support their contentions. Rather, we are persuaded by Dr. Peckerar’s testimony that as a general rule in semiconductor process technology, a bare silicon surface should not be left unpassivated after processing. Elemental silicon is highly chemically reactive. As such, the bare surface is a “magnet” for defects and contamination. Leaving the tunnel oxide in place across the entire substrate backside would reduce this problem. Ex. 2001 ¶ 142. Dr. Peckerar further explains that a person of ordinary skill in the art would have known how to avoid shorting and leakage. In particular, he testifies that the manner by which charge is transported through a tunnel oxide can be controlled by adjusting manufacturing parameters such as time, temperature, thickness, and ambient impurities. A POSITA would plainly have adjusted these parameters to ensure that the tunnel oxide operates as intended (i.e., minimizes recombinant losses while transporting charge carriers to the backside of the solar cell) while avoiding undesirable leakage current. Because unwanted leakage charge can be avoided via other means during manufacture, there would have been no reason to reduce the physical extent of the tunnel oxide. Ex. 2001 ¶ 152 (referring to Ex. 2001 ¶¶ 149–151). Moreover, Dr. Peckerar testifies that “Dr. Banerjee also appears to be arguing that incorporation of impurities into the oxide will produce a MOSFET-like structure, with the contaminated oxide acting as a MOS gate leading to enhanced leakage,” but, for that to occur, “the source and drain areas would need to be of the same type.” Ex. 2001 ¶ 159. Here however, “the tunnel oxide layer is located between an n-type polysilicon layer and p-type frontside emitter layer” so “[n]o MOSFET-like structure can form because the source and drain are of different types.” Ex. 2001 ¶ 159. Neither Petitioner nor Dr. Banerjee address or dispute this testimony. See generally Reply; Ex. 1037. We credit Dr. Peckerar’s testimony in this regard. Without an apparent reason to modify the teachings of Jin and Feldmann to” slip op. at 19
- Obviousness (§103) › Motivation to combine / reasonable expectation of success › HindsightNot shown unpatentableMotivation not foundNot shown unpatentable
“On this complete trial record, we agree with Patent Owner. It is improper to base a conclusion of obviousness upon facts gleaned only through hindsight. “The invention must be viewed not after the blueprint has been drawn by the inventor, but as it would have been perceived in the state of the art that existed at the time the invention was made.” Sensonics, Inc. v. Aerosonic Corp., 81 F.3d 1566, 1570 (Fed. Cir. 1996) (citing Interconnect Planning Corp. v. Feil, 774 F.2d 1132, 1138 (Fed. Cir. 1985)). Therefore, “to establish a prima facie case of obviousness based on a combination of elements disclosed in the prior art, the [Petitioner] must articulate the basis on which it concludes that it would have been obvious to make the claimed invention.” Id. Impermissible hindsight is inferred when the specific understanding or principle within the knowledge of one of ordinary skill in the art that would motivate one (with no knowledge of the claimed invention) to make the proposed combination has not been explained. In re Rouffet, 149 F.3d 1350, 1358 (Fed. Cir. 1998).” slip op. at 17
Patent outcomesUS 10,230,009 unpatentableClaim construction§ 103 obviousnesscites Phillips · KSR · GrahamPatents in suitUS 10,230,009 - Runergy Alabama Inc. / Runergy USA Inc. et al. v. Trina Solar Co., Ltd.All claims unpatentablePTAB · Apr 15, 2026 · IPR2025-00917 · APJ Debra L Dennett · IPR · Final written decision
Claims 1–17 are unpatentable under § 103 over Chang and Jin, alone or with Seo or Watanabe; the Jin and Feldmann grounds were not shown.
RulingsFinal written decision- Skill levelSkill level petitioner adoptedDecided for petitioner
“In light of the record before us, we adopt Petitioner’s proposal regarding the level of ordinary skill in the art. Based on our review of the ’009 patent and the prior art of record, we determine that the definition offered by Petitioner comports with the qualifications a person would have needed to understand the ’009 patent and the prior art.” slip op. at 10
- Expert testimonyPatent owner expert creditedDecided for patent owner
“We acknowledge Dr. Banerjee’s testimony that the combination of Jin’s gap-T isolation region would prevent shorting and that extending the tunnel oxide layer the edge “could trap impurities and create negative fixed oxide charges, which could then create a p-type inversion in the n-type base substrate, leading to a leakage path to the p-type emitter on the front of the solar cell” (Ex. 1003 ¶ 116 (emphasis added)) but are not convinced by his equivocal testimony. Notably too, neither Jin nor Feldmann discuss issues relating to trapped impurities and Petitioner, as well as Dr. Banerjee, fail to direct our attention to any record evidence to support their contentions. Rather, we are persuaded by Dr. Peckerar’s testimony that as a general rule in semiconductor process technology, a bare silicon surface should not be left unpassivated after processing. Elemental silicon is highly chemically reactive. As such, the bare surface is a “magnet” for defects and contamination. Leaving the tunnel oxide in place across the entire substrate backside would reduce this problem. Ex. 2001 ¶ 142. Dr. Peckerar further explains that a person of ordinary skill in the art would have known how to avoid shorting and leakage. In particular, he testifies that the manner by which charge is transported through a tunnel oxide can be controlled by adjusting manufacturing parameters such as time, temperature, thickness, and ambient impurities. A POSITA would plainly have adjusted these parameters to ensure that the tunnel oxide operates as intended (i.e., minimizes recombinant losses while transporting charge carriers to the backside of the solar cell) while avoiding undesirable leakage current. Because unwanted leakage charge can be avoided via other means during manufacture, there would have been no reason to reduce the physical extent of the tunnel oxide. Ex. 2001 ¶ 152 (referring to Ex. 2001 ¶¶ 149–151). Moreover, Dr. Peckerar testifies that “Dr. Banerjee also appears to be arguing that incorporation of impurities into the oxide will produce a MOSFET-like structure, with the contaminated oxide acting as a MOS gate leading to enhanced leakage,” but, for that to occur, “the source and drain areas would need to be of the same type.” Ex. 2001 ¶ 159. Here however, “the tunnel oxide layer is located between an n-type polysilicon layer and p-type frontside emitter layer” so “[n]o MOSFET-like structure can form because the source and drain are of different types.” Ex. 2001 ¶ 159. Neither Petitioner nor Dr. Banerjee address or dispute this testimony. See generally Reply; Ex. 1037. We credit Dr. Peckerar’s testimony in this regard.” slip op. at 19
- Obviousness (§103) › Motivation to combine / reasonable expectation of success › HindsightMotivation not foundNot shown unpatentableNot shown unpatentable
“On this complete trial record, we agree with Patent Owner. It is improper to base a conclusion of obviousness upon facts gleaned only through hindsight. “The invention must be viewed not after the blueprint has been drawn by the inventor, but as it would have been perceived in the state of the art that existed at the time the invention was made.” Sensonics, Inc. v. Aerosonic Corp., 81 F.3d 1566, 1570 (Fed. Cir. 1996) (citing Interconnect Planning Corp. v. Feil, 774 F.2d 1132, 1138 (Fed. Cir. 1985)). Therefore, “to establish a prima facie case of obviousness based on a combination of elements disclosed in the prior art, the [Petitioner] must articulate the basis on which it concludes that it would have been obvious to make the claimed invention.” Id. Impermissible hindsight is inferred when the specific understanding or principle within the knowledge of one of ordinary skill in the art that would motivate one (with no knowledge of the claimed invention) to make the proposed combination has not been explained. In re Rouffet, 149 F.3d 1350, 1358 (Fed. Cir. 1998).” slip op. at 17
- Obviousness (§103) › Motivation to combine / reasonable expectation of successMotivation foundUnpatentableUnpatentable
“Patent Owner focuses on Chang’s description in paragraph 76 of a single configuration in which the emitter area and back surface field area are not adjacent to each other, thus eliminating “the necessity of performing an isolation process when the emitter area [] and the back surface field are [] are formed to be adjacent to each other.” Resp. 42 (citing Ex. 1013 ¶ 76). In so doing, Patent Owner side steps Chang’s unambiguous definition that “‘entirely formed’ means that an element such as a layer is formed over an entire surface without an empty area or a non-coverage area, or is formed over an entire area excluding pre-designated or inevitably formed regions such as periphery region, isolation region or the like.” Ex. 1013 ¶¶ 45, 51, 56, 62 (emphasis added). Chang discloses that a first tunneling layer, a first portion of an emitter area, a second tunneling layer, and a back surface field area may each be “formed over an entire area excluding pre-designated or inevitably formed regions such as periphery region, isolation region or the like.” Id. Chang’s definition of “entirely formed” (“excluding pre-designated or inevitably formed regions such as periphery region, isolation region or the like”) implies use of a mask. See Chang ¶ 62; Tr. 15:20–17:11. Dr. Banerjee testifies that the need to electrically isolate the emitter region from the back surface field was well known in the field, and both Chang and Jin teach backside isolation regions. Ex. 1003 ¶¶ 73, 217 (citing Ex. 1023 § 1). Chang also discloses that the emitter area may be formed by thermal diffusion, ion implantation or the like. Ex. 1013 ¶ 98. Petitioner persuasively argues that Chang’s disclosure of thermal diffusion of the emitter layer would result in dopants diffused into not only the top surface of the substrate, but also the exposed lateral surfaces, a problem also noted in Jin. See Pet. 11–12; Reply 6–7; Ex. 1003 ¶ 71; Ex. 1009 ¶¶ 57–58. Jin discloses avoiding shorting of the emitter layer and back surface field layer by edge isolation on the back surface field layer using a mask to create a “gap-T.” Ex. 1009 ¶¶ 57–58, 83. Chang discloses excluding a tunneling layer and a base surface field area from periphery region and isolation region. Ex. 1013 ¶¶ 56, 62. Using a mask, as implied in Chang and explicitly disclosed in Jin, would “pre-designate” and/or “inevitably form” the regions where the tunneling layer and back surface field area are excluded. We credit Dr. Banerjee’s testimony that one of ordinary skill in the art reviewing Chang would therefore understand the importance of implementing the isolation region in Chang’s device, and would therefore be motivated to look to other references, such as Jin (which was assigned to the same original assignee as Chang, LG Electronics, EX1009-Jin, face; EX1013-Chang, face) to understand details regarding Chang’s isolation region.” slip op. at 32
Patent outcomesUS 10,230,009 unpatentable§ 103 obviousnesscites Phillips · KSR · GrahamPatents in suitUS 10,230,009 - Runergy Alabama Inc. / Runergy USA Inc. et al. v. Trina Solar Co., Ltd.All claims unpatentablePTAB · Apr 15, 2026 · IPR2025-00006 · APJ Debra L Dennett · IPR · Final written decision
Claims 1–17 are unpatentable under § 103, principally over Chang and Jin; the Board rejected the Jin and Feldmann combinations for lack of a reason to combine.
RulingsFinal written decision- Skill levelSkill level petitioner adoptedDecided for petitioner
“In light of the record before us, we adopt Petitioner’s proposal regarding the level of ordinary skill in the art. Based on our review of the ’009 patent and the prior art of record, we determine that the definition offered by Petitioner comports with the qualifications a person would have needed to understand the ’009 patent and the prior art.” slip op. at 10
- Claim Construction › Threshold & procedure › Whether a term needs construction (O2 Micro)No construction neededOther
“Petitioner contends that “[n]o claim construction is believed to be necessary to resolve this Petition.” Pet. 24. Patent Owner does not address claim construction. See generally Resp.; Sur-reply. For purposes of this Decision, we need not expressly construe any claim terms. See Vivid Techs., Inc. v. Am. Sci. & Eng’g, Inc., 200 F.3d 795, 803 (Fed. Cir. 1999) (holding that “only those terms need be construed that are in controversy, and only to the extent necessary to resolve the controversy”); see also Nidec Motor Corp. v. Zhongshan Broad Ocean Motor Co., 868 F.3d 1013, 1017 (Fed. Cir. 2017) (citing Vivid Techs. in the context of an inter partes review).” slip op. at 11
- Obviousness (§103) › Motivation to combine / reasonable expectation of success › HindsightNot shown unpatentableMotivation not foundNot shown unpatentable
“However, Petitioner proposes to remove the tunnel oxide layer from the edge and offers little explanation of why the skilled artisan would apply Jin’s gap- T isolation region to both of Feldmann’s polysilicon and tunnel oxide layers. As noted above, Petitioner states that the skilled artisan would have included Jin’s gap-T isolation region in order to prevent shorting. Pet. 26. Petitioner’s reasoning is questionable—supported only by the conclusory testimony of Dr. Banerjee. Dr. Banerjee’s testimony offers no more evidentiary support than provided in the Petition. Compare Ex. 1003 ¶ 116 with Pet. 26). Petitioner cannot satisfy its burden of proving obviousness by employing “mere conclusory statements.” See Magnum, 829 F.3d at 1380. We acknowledge Dr. Banerjee’s testimony that the combination of Jin’s gap-T isolation region would prevent shorting and that extending the tunnel oxide layer the edge “could trap impurities and create negative fixed oxide charges, which could then create a p-type inversion in the n-type base substrate, leading to a leakage path to the p-type emitter on the front of the solar cell” (Ex. 1003 ¶ 116 (emphasis added)) but are not convinced by his equivocal testimony. Notably too, neither Jin nor Feldmann discuss issues relating to trapped impurities and Petitioner, as well as Dr. Banerjee, fail to direct our attention to any record evidence to support their contentions. Rather, we are persuaded by Dr. Peckerar’s testimony that as a general rule in semiconductor process technology, a bare silicon surface should not be left unpassivated after processing. Elemental silicon is highly chemically reactive. As such, the bare surface is a “magnet” for defects and contamination. Leaving the tunnel oxide in place across the entire substrate backside would reduce this problem. Ex. 2001 ¶ 142. Dr. Peckerar further explains that a person of ordinary skill in the art would have known how to avoid shorting and leakage. In particular, he testifies that the manner by which charge is transported through a tunnel oxide can be controlled by adjusting manufacturing parameters such as time, temperature, thickness, and ambient impurities. A POSITA would plainly have adjusted these parameters to ensure that the tunnel oxide operates as intended (i.e., minimizes recombinant losses while transporting charge carriers to the backside of the solar cell) while avoiding undesirable leakage current. Because unwanted leakage charge can be avoided via other means during manufacture, there would have been no reason to reduce the physical extent of the tunnel oxide. Ex. 2001 ¶ 152 (referring to Ex. 2001 ¶¶ 149–151). Moreover, Dr. Peckerar testifies that “Dr. Banerjee also appears to be arguing that incorporation of impurities into the oxide will produce a MOSFET-like structure, with the contaminated oxide acting as a MOS gate leading to enhanced leakage,” but, for that to occur, “the source and drain areas would need to be of the same type.” Ex. 2001 ¶ 159. Here however, “the tunnel oxide layer is located between an n-type polysilicon layer and p-type frontside emitter layer” so “[n]o MOSFET-like structure can form because the source and drain are of different types.” Ex. 2001 ¶ 159. Neither Petitioner nor Dr. Banerjee address or dispute this testimony. See generally Reply; Ex. 1037. We credit Dr. Peckerar’s testimony in this regard.” slip op. at 19
- Obviousness (§103) › Motivation to combine / reasonable expectation of successUnpatentableMotivation foundUnpatentable
“configuration in which the emitter area and back surface field area are not adjacent to each other, thus eliminating “the necessity of performing an isolation process when the emitter area [] and the back surface field are [] are formed to be adjacent to each other.” Resp. 42 (citing Ex. 1013 ¶ 76). In so doing, Patent Owner side steps Chang’s unambiguous definition that “‘entirely formed’ means that an element such as a layer is formed over an entire surface without an empty area or a non-coverage area, or is formed over an entire area excluding pre-designated or inevitably formed regions such as periphery region, isolation region or the like.” Ex. 1013 ¶¶ 45, 51, 56, 62 (emphasis added). Chang discloses that a first tunneling layer, a first portion of an emitter area, a second tunneling layer, and a back surface field area may each be “formed over an entire area excluding pre-designated or inevitably formed regions such as periphery region, isolation region or the like.” Id. Chang’s definition of “entirely formed” (“excluding pre-designated or inevitably formed regions such as periphery region, isolation region or the like”) implies use of a mask. See Chang ¶ 62; Tr. 15:20–17:11. Dr. Banerjee testifies that the need to electrically isolate the emitter region from the back surface field was well known in the field, and both Chang and Jin teach backside isolation regions. Ex. 1003 ¶¶ 73, 217 (citing Ex. 1023 § 1). Chang also discloses that the emitter area may be formed by thermal diffusion, ion implantation or the like. Ex. 1013 ¶ 98. Petitioner persuasively argues that Chang’s disclosure of thermal diffusion of the emitter layer would result in dopants diffused into not only the top surface of the substrate, but also the exposed lateral surfaces, a problem also noted in Jin. See Pet. 11–12; Reply 6–7; Ex. 1003 ¶ 71; Ex. 1009 ¶¶ 57–58. Jin discloses avoiding shorting of the emitter layer and back surface field layer by edge isolation on the back surface field layer using a mask to create a “gap-T.” Ex. 1009 ¶¶ 57–58, 83. Chang discloses excluding a tunneling layer and a base surface field area from periphery region and isolation region. Ex. 1013 ¶¶ 56, 62. Using a mask, as implied in Chang and explicitly disclosed in Jin, would “pre-designate” and/or “inevitably form” the regions where the tunneling layer and back surface field area are excluded. We credit Dr. Banerjee’s testimony that one of ordinary skill in the art reviewing Chang would therefore understand the importance of implementing the isolation region in Chang’s device, and would therefore be motivated to look to other references, such as Jin (which was assigned to the same original assignee as Chang, LG Electronics, EX1009-Jin, face; EX1013-Chang, face) to understand details regarding Chang’s isolation region.” slip op. at 32
Patent outcomesUS 10,230,009 unpatentableClaim construction§ 103 obviousnesscites Phillips · KSR · GrahamPatents in suitUS 10,230,009 - Runergy Alabama Inc. / Runergy USA Inc. et al. v. Trina Solar Co., Ltd.All claims unpatentablePTAB · Apr 15, 2026 · IPR2025-00918 · APJ Avelyn M Ross · IPR · Final written decision
Claims 1–11 are unpatentable under § 103 over Chang and Jin; the Board rejected the Jin and Feldmann based grounds for lack of a reason to combine without hindsight.
RulingsFinal written decision- Skill levelSkill level petitioner adoptedDecided for petitioner
“Petitioner contends that a person of ordinary skill in the art would have been someone with an advanced degree involving the disciplines of electrical engineering, applied physics, chemistry, or materials science, and at least two years of experience designing, developing, or researching in the field. Alternatively, that person would have had a bachelor’s degree in electrical engineering, applied physics, or materials science, and at least three years of experience designing, developing, or researching in the field.” slip op. at 9
- Claim Construction › Threshold & procedure › Whether a term needs construction (O2 Micro)No construction neededOther
“Petitioner contends that “[n]o claim construction is believed to be necessary to resolve this Petition.” Pet. 23. And, Patent Owner does not address claim construction. See generally PO Resp. As neither party proposes an express construction for our consideration and because we determine that an express claim construction is not necessary for us to render a decision in this matter, we do not construe any claim terms. See Vivid Techs., Inc. v. Am. Sci. & Eng’g, Inc., 200 F.3d 795, 803 (Fed. Cir. 1999) (holding that “only those terms need be construed that are in controversy, and only to the extent necessary to resolve the controversy”); see also Nidec Motor Corp. v. Zhongshan Broad Ocean Motor Co., 868 F.3d 1013, 1017 (Fed. Cir. 2017) (citing Vivid Techs. in the context of an inter partes review).” slip op. at 10
- Obviousness (§103) › Motivation to combine / reasonable expectation of success › HindsightNot shown unpatentableMotivation not foundNot shown unpatentable
“base a conclusion of obviousness upon facts gleaned only through hindsight. “The invention must be viewed not after the blueprint has been drawn by the inventor, but as it would have been perceived in the state of the art that existed at the time the invention was made.” Sensonics, Inc. v. Aerosonic Corp., 81 F.3d 1566, 1570 (Fed. Cir. 1996) (citing Interconnect Planning Corp. v. Feil, 774 F.2d 1132, 1138 (Fed. Cir. 1985)). Therefore, “to establish a prima facie case of obviousness based on a combination of elements disclosed in the prior art, the [Petitioner] must articulate the basis on which it concludes that it would have been obvious to make the claimed invention.” Id. Impermissible hindsight is inferred when the specific understanding or principle within the knowledge of one of ordinary skill in the art that would motivate one (with no knowledge of the claimed invention) to make the proposed combination has not been explained. In re Rouffet, 149 F.3d 1350, 1358 (Fed. Cir. 1998).” slip op. at 16
- Obviousness (§103) › Motivation to combine / reasonable expectation of successUnpatentableMotivation foundUnpatentable
“Patent Owner focuses on Chang’s description in paragraph 76 of a single configuration in which the emitter area and back surface field area are not adjacent to each other, thus eliminating “the necessity of performing an isolation process when the emitter area [] and the back surface field are [] are formed to be adjacent to each other.” PO Resp. 42–43 (citing Ex. 1013 ¶ 76). But, in so doing, Patent Owner side steps Chang’s unambiguous definition that “‘entirely formed’ means that an element such as a layer is formed over an entire surface without an empty area or a non-coverage area, or is formed over an entire area excluding pre-designated or inevitably formed regions such as periphery region, isolation region or the like.” Ex. 1013 ¶¶ 45, 51, 56, 62 (emphasis added). Chang discloses that a first tunneling layer, a first portion of an emitter area, a second tunneling layer, and a back surface field area may each be “formed over an entire area excluding pre-designated or inevitably formed regions such as periphery region, isolation region or the like.” Ex. 1013 ¶¶ 45, 51, 56, 62. Chang’s definition of “entirely formed” (“excluding pre-designated or inevitably formed regions such as periphery region, isolation region or the like”) implies use of a mask. See Ex. 1013 ¶ 62; Tr. 15:20– 17:11. Dr. Banerjee testifies that the need to electrically isolate the emitter region from the back surface field was well known in the field, and both Chang and Jin teach backside isolation regions. Ex. 1003 ¶¶ 70–81, 91–96, 200 (citing Ex. 1026 § 1 and stating that “[b]oth Chang and Jin likewise teach backside isolation regions”). Chang also discloses that the emitter area may be formed by “thermal diffusion, ion implantation or the like.” Ex. 1013 ¶ 98. Petitioner persuasively argues that Chang’s disclosure of thermal diffusion of the emitter layer would result in dopants diffused into not only the top surface of the substrate, but also the exposed lateral surfaces, a problem also noted in Jin. See Pet. 11–12; Pet. Reply 6–7; Ex. 1003 ¶ 71; Ex. 1009 ¶¶ 57–58. Jin discloses avoiding shorting of the emitter layer and back surface field layer by edge isolation on the back surface field layer using a mask to create a “gap-T.” Ex. 1009 ¶¶ 57–58, 83. Chang discloses excluding the second tunneling layer and a base surface field area from periphery region and isolation portion. Ex. 1013 ¶¶ 56, 62. Using a mask, as implied in Chang and explicitly disclosed in Jin, would “pre-designate” and/or “inevitably form” the regions where the tunneling layer and back surface field area are excluded. We credit Dr. Banerjee’s testimony that one of ordinary skill in the art “reviewing Chang would therefore understand the importance of implementing the isolation region in Chang’s device, and would therefore be motivated to look to other references, such as Jin (which was assigned to the same original assignee as Chang, LG Electronics, EX1009-Jin, face; EX1013-Chang, face) to understand details regarding Chang’s isolation region.” Ex. 1003 ¶ 201.” slip op. at 33
Patent outcomesUS 9,722,104 unpatentableClaim construction§ 103 obviousnesscites Phillips · KSR · GrahamPatents in suitUS 9,722,104 - Runergy Alabama Inc. / Runergy USA Inc. et al. v. Trina Solar Co., Ltd.All claims unpatentablePTAB · Apr 15, 2026 · IPR2025-00186 · APJ Avelyn M Ross · IPR · Final written decision
Claims 1–11 are unpatentable under § 103 over Chang and Jin; the Board found the combination disclosed the claimed isolation portion and supported the challenged claims.
RulingsFinal written decision- Skill levelSkill level petitioner adoptedDecided for petitioner
“Petitioner contends that a person of ordinary skill in the art would have been someone with an advanced degree involving the disciplines of electrical engineering, applied physics, chemistry, or materials science, and at least two years of experience designing, developing, or researching in the field. Alternatively, that person would have had a bachelor’s degree in electrical engineering, applied physics, or materials science, and at least three years of experience designing, developing, or researching in the field. Pet. 4 (citing Ex. 1003 ¶ 49). Patent Owner does not address the level of ordinary skill in the art. See generally PO Resp; Sur-reply. In light of the complete trial record before us, we adopt Petitioner’s proposal regarding the level of ordinary skill in the art. Based on our review of the ’104 patent and the prior art of record, we determine that the definition offered by Petitioner comports with the qualifications a person would have needed to understand the ’104 patent and the prior art.” slip op. at 9
- Claim Construction › Threshold & procedure › Whether a term needs construction (O2 Micro)No construction neededNot reached
“C. Claim Construction We construe claim terms according to the standard set forth in Phillips v. AWH Corp., 415 F.3d 1303, 1312–17 (Fed. Cir. 2005) (en banc); 37 C.F.R. § 42.100(b). Under Phillips, we give claim terms “their ordinary and customary meaning.” Phillips, 415 F.3d at 1312. “[T]he ordinary and customary meaning of a claim term is the meaning that the term would have to a person of ordinary skill in the art in question at the time of the invention.” Id. at 1313. “Importantly, the person of ordinary skill in the art is deemed to read the claim term not only in the context of the particular claim in which the disputed term appears, but in the context of the entire patent, including the specification.” Id. Petitioner contends that “[n]o claim construction is believed to be necessary to resolve this Petition.” Pet. 23. And, Patent Owner does not address claim construction. See generally PO Resp. As neither party proposes an express construction for our consideration and because we determine that an express claim construction is not necessary for us to render a decision in this matter, we do not construe any claim terms. See Vivid Techs., Inc. v. Am. Sci. & Eng’g, Inc., 200 F.3d 795, 803 (Fed. Cir. 1999) (holding that “only those terms need be construed that are in controversy, and only to the extent necessary to resolve the controversy”); see also Nidec Motor Corp. v. Zhongshan Broad Ocean Motor Co., 868 F.3d 1013, 1017 (Fed. Cir. 2017) (citing Vivid Techs. in the context of an inter partes review).” slip op. at 10
- Expert testimonyPetitioner expert discountedPatent owner expert creditedMixed
“edge and offers little explanation of why the skilled artisan would apply Jin’s gap- T isolation region to both of Feldmann’s polysilicon and tunnel oxide layers. As noted above, Petitioner states that the skilled artisan would have included Jin’s gap-T isolation region in order to prevent shorting. Pet. 25. Petitioner’s reasoning is questionable—supported only by the conclusory testimony of Dr. Banerjee. Dr. Banerjee’s testimony offers no more evidentiary support than provided in the Petition. Compare Ex. 1003 ¶ 113, with Pet. 25. Petitioner cannot satisfy its burden of proving obviousness by employing “mere conclusory statements.” Magnum Oil, 829 F.3d at 1380. We acknowledge Dr. Banerjee’s testimony that the combination of Jin’s gap-T isolation region would prevent shorting and that extending the tunnel oxide layer the edge “could trap impurities and create negative fixed oxide charges, which could then create a p-type inversion in the n-type base substrate, leading to a leakage path to the p-type emitter on the front of the solar cell” (Ex. 1003 ¶ 113 (emphasis added)) but are not convinced by his equivocal testimony. Notably too, neither Jin nor Feldmann discuss issues relating to trapped impurities and Petitioner, as well as Dr. Banerjee, fail to direct our attention to any record evidence to support their contentions. Rather, we are persuaded by Dr. Peckerar’s testimony that as a general rule in semiconductor process technology, a bare silicon surface should not be left unpassivated after processing. Elemental silicon is highly chemically reactive. As such, the bare surface is a “magnet” for defects and contamination. Leaving the tunnel oxide in place across the entire substrate backside would reduce this problem. Ex. 2001 ¶ 142. Dr. Peckerar further explains that a person of ordinary skill in the art would have known how to avoid shorting and leakage. In particular, he testifies that the manner by which charge is transported through a tunnel oxide can be controlled by adjusting manufacturing parameters such as time, temperature, thickness, and ambient impurities. A POSITA would plainly have adjusted these parameters to ensure that the tunnel oxide operates as intended (i.e., minimizes recombinant losses while transporting charge carriers to the backside of the solar cell) while avoiding undesirable leakage current. Because unwanted leakage charge can be avoided via other means during manufacture, there would have been no reason to reduce the physical extent of the tunnel oxide. Ex. 2001 ¶ 152 (referring to Ex. 2001 ¶¶ 149–151). Moreover, Dr. Peckerar testifies that “Dr. Banerjee also appears to be arguing that incorporation of impurities into the oxide will produce a MOSFET-like structure, with the contaminated oxide acting as a MOS gate leading to enhanced leakage,” but, for that to occur, “the source and drain areas would need to be of the same type.” Ex. 2001 ¶ 159. Here however, “the tunnel oxide layer is located between an n-type polysilicon layer and p-type frontside emitter layer” so “[n]o MOSFET-like structure can form because the source and drain are of different types.” Ex. 2001” slip op. at 18
- Obviousness (§103) › Motivation to combine / reasonable expectation of success › HindsightNot shown unpatentableMotivation not foundNot shown unpatentable
“base a conclusion of obviousness upon facts gleaned only through hindsight. “The invention must be viewed not after the blueprint has been drawn by the inventor, but as it would have been perceived in the state of the art that existed at the time the invention was made.” Sensonics, Inc. v. Aerosonic Corp., 81 F.3d 1566, 1570 (Fed. Cir. 1996) (citing Interconnect Planning Corp. v. Feil, 774 F.2d 1132, 1138 (Fed. Cir. 1985)). Therefore, “to establish a prima facie case of obviousness based on a combination of elements disclosed in the prior art, the [Petitioner] must articulate the basis on which it concludes that it would have been obvious to make the claimed invention.” Id. Impermissible hindsight is inferred when the specific understanding or principle within the knowledge of one of ordinary skill in the art that would motivate one (with no knowledge of the claimed invention) to make the proposed combination has not been explained. In re Rouffet, 149 F.3d 1350, 1358 (Fed. Cir. 1998).” slip op. at 16
Patent outcomesUS 9,722,104 unpatentableClaim construction§ 103 obviousnesscites Phillips · KSR · GrahamPatents in suitUS 9,722,104
Holdings, summaries, rulings, issues, outcomes, winners and claim constructions shown for a decision were generated by a large language model reading the opinion. They are a guide to the decision, not the decision. Confirm every one against the court's own text before relying on it. Outcomes read from the patent owner’s side. Party names are extracted from the decision and are missing on about 900 short Director denials and scans, which carry the trial number instead.