In a decision rendered by George Wei J of the Singapore High Court dated 8 December 2017, the High Court upheld the validity of the Rohm and Haas Electronic Materials CMP Holdings, Inc’s patent, granted a declaration of the said patent’s validity, as well as a declaration that the asserted claims of the patent were infringed by NexPlanar Corporation and Wah Lee Tech (Singapore) Pte Ltd.
(A) Who are the parties involved in this case?
Rohm and Haas Electronic Materials CMP Holdings, Inc (formerly known as Rodel Holdings, Inc) (Plaintiff)
- A company incorporated in the United States of America and the subsidiary of Dow Chemical Company.
- It was the registered proprietor of Singapore Patent No. 43335, in respect of a “Polymeric Polishing Pad Containing Hollow Polymeric Microelements” (“the Patent”), which expired on 2 August 2013.
- The claimed invention relates to the field of semiconductor manufacturing. Semiconductors are built on thin round discs or wafers, commonly made of silicon. One of the stages in wafer manufacturing is known as “chemical mechanical polishing / planarization (“CMP”), which refers to the process of smoothening a surface by means of a combination of chemical and mechanical forces. In the CMP process, the wafer is pressed against a polishing pad, and both the wafer and the pad rotate while in contact with each other. At the same time, an abrasive and corrosive chemical slurry is dispensed onto the polishing pad to aid in the smoothening of the wafer.
- The claimed invention is a polishing pad used to polish or planarize the surface of an electronic substrate such as a wafer. This pad includes a polymeric matrix or substrate that is embedded with hollow polymeric microelements. The pad comprised a “work surface” with microelements that come into direct contact with the work-piece, as well as another “subsurface” of microelements. The microelements at the work surface are less rigid than those embedded in the subsurface. As the work surface wears out, the subsurface becomes the new work surface. The regeneration of the subsurface as the new work surface allows for a more consistent and even polishing of the wafer.
NexPlanar Corporation (1st Defendant)
- US-incorporated company in the business of designing and manufacturing CMP pads
- Wah Lee Tech (Singapore) Pte Ltd (2nd Defendant)
- A locally-incorporated company which imports and purchases CMP pads from suppliers such as the 1st Defendant and resells the CMP pads to its customers in Singapore.
(B) What actually happened?
The Plaintiff brought a suit against the Defendants for alleged infringement of the Patent. According to the Plaintiff, certain CMP pads (“NexPlanar Pads”) manufactured and sold by the 1st Defendant infringed the asserted claims of the Patent, i.e. 8 out of the 21 claims subsisting in the Patent. The NexPlanar Pads in question corresponded to 12 of the 1st Defendant’s pad models, i.e. “NEX4-6035-30S”, “NEXX-0901”, “NEXX-09NH-30S-25-70TS-4CF”, “NEXX-09NP-30S-25-70TS-4CF”, “NEXX-09V1”, “E7980-30S-25-70TS-4CF”, “NEXX-09P6-30S”, “NEXX-09P7-30S” w/ sub-pad 4”, “NEXPLANAR PAD-NEXX-09NF-30S-25”, “NEXPLANAR PAD NEXX-09NP-30S-25-70TS-40F”, “NEXX-09V1-30S” and “Nexx-09NH”.
The Plaintiff alleged that the following acts by the Defendants between 2010 and 2012 constituted infringement of the Patent:
- 1st Defendant’s sale of (or offer to sell) the NexPlanar Pads to the 2nd Defendant around late 2010 to the first quarter of 2012, for the purpose of the 2nd Defendant’s sale, offer to sell, importation, use or keeping of the NexPlanar Pads;
- 2nd Defendant’s importation, use or keeping of the NexPlanar Pads around late 2010 to the first quarter of 2012; and
- 2nd Defendant’s sale of (or offer to sell) the NexPlanar Pads to a company known as United Microelectronic Corporation (“United Microelectronic”) between late 2010 and the first quarter of 2012.
The Plaintiff further alleged that the 1st Defendant directed, authorised, procured, assisted or enabled 2nd Defendant to infringe the Patent, and/or acted in concert with the 2nd Defendant pursuant to a common design to infringe the Patent.
The Plaintiff hence claimed against the Defendants for:
- a declaration that the Patent was valid and that it was infringed by the Defendants;
- an injunction to restrain the Defendants from making, disposing of, offering to dispose of, using, importing and/or keeping products which infringe the Patent;
- an injunction to restrain the 1st Defendant from:
- directing, authorising, procuring, assisting or enabling the 2nd Defendant to infringe the Patent; and/or
- acting in concert with the 2nd Defendant in furtherance of the said infringement pursuant to a common design;
- an inquiry as to the damages or an account of profits made by the Defendants, and an order for payment for all sums found to be due upon making the inquiry or account;
- an order for the delivery up and/or destruction of all infringing products which are in the possession, custody or control of the Defendants;
- full discovery of all matters relating to this action; and
- interest, costs and any further relief.
The Defendants denied infringement on the basis that the NexPlanar Pads did not fall within the asserted claims of the Patent. It asserted that the plain and ordinary language of claim 1 of the Patent informs a skilled reader that the claimed invention is a conditioned or “broken-in” pad which is in use for polishing an electronic substrate, and therefore did not cover new, as-received and unconditioned pads. In contrast, the NexPlanar Pads dealt with by the Defendants were new, as-received and unconditioned pads, and therefore did not fall within the scope of the asserted claims. The Defendants also further denied being joint tortfeasors and assert that they did not engage in any common design to infringe the Patent, their relationship being purely that of a buyer and seller. As a defence and counterclaim for revocation of the Patent, the Defendants contended that the Patent has always been invalid for the following reasons:
- Patent was not novel as it was anticipated by prior use and sale of Plaintiff’s own “IC-1000” pads to Intel Corporation before the Patent’s priority date of 19 August 1992;
- Patent did not involve an inventive step, as prior art rendered the invention obvious;
- Specification of the Patent did not disclose the invention with sufficient clarity and completeness for it to be performed by a person skilled in the art.
The Defendants further contended that even if the Patent was found to be valid and infringed, no question of injunction can arise as the Patent has already expired.
The Defendants counterclaimed against the Plaintiff for:
- Declaration that Patent has always been invalid;
- Order that the Patent be revoked;
- Declaration that the Defendants have not infringed the Patent; and
- Costs and any further relief.
(C) What is/are the present issue(s) in dispute?
- The validity of the Patent – whether the Patent was novel, involved an inventive step, and sufficiently disclosed the invention;
- If the Patent was valid, whether it was infringed by the Defendant’s CMP pads and actions; and
- If so, the appropriate remedies for infringement.
Issue 1: Validity of the Patent
The legal principles
The law on novelty is found in Section 14 of the Patents Act. Section 14(1) provides that “an invention shall be taken to be new if it does not form part of the state of the art”. Section 14(2) provides that the state of the art is assessed on a worldwide basis with no geographical or territorial limits. It comprises “all matter” made available to the public before the priority date, i.e. 19 August 1992 in the present case.
The burden is on the party challenging the novelty of a granted patent to adduce evidence of a prior disclosure that led to the claimed invention forming part of the state of the art. However, the disclosure of information under the cover of an obligation of confidence is a non-prejudicial disclosure. The court may find the existence of an obligation of confidence even in the absence of an express confidentiality agreement or undertaking. In reaching this determination, the court will consider all circumstances in which the disclosure was made, including the purpose of the disclosure and whether there was a common commercial object and/or substantial cooperation between the recipient and the proprietor of the patent.
There are essentially 4 steps in the assessment of novelty:
- Determine state of the art as at priority date based on evidence and material before the court;
- Interpret the prior art material from perspective of skilled reader at the date the material or information entered the prior art and without use of hindsight and mosaicking, and determine what each piece of prior art disclose;
- Interpret scope of claimed invention from perspective of skilled reader and by reference to the patent specifications;
- Compare prior art against claimed invention and reach a determination as to whether the prior art anticipates the claimed invention.
- The parties positions on whether the Patent was anticipated by the prior use and sale of the “IC-1000” pads
The main issue of the dispute here was whether the Plaintiff’s prior sale and disposal of “IC-1000” pads were made under obligations of confidentiality, such that the Patent was not anticipated by the disclosure.
In this regard, the Defendants had argued that the Patent was anticipated by: (a) sale of “IC-1000” pads to Intel before the priority date; (b) disclosure of samples of “IC-1000” pads to SEMATECH, a non-profit consortium that performs research and development to advance chip manufacturing and/or presentations covering “IC-1000” pads at a Sematech conference; and (c) Plaintiff’s alleged provision of a brochure to an Intel personnel. Conversely, the Plaintiff submitted that the Patent was not anticipated by prior use and sale of “IC-1000” pads as: (a) “IC-1000” pads sold to Intel before priority date were merely experimental versions of the Patent; (b) Intel was under an express obligation of confidentiality owed to the Plaintiff in respect of the sale made pursuant to a joint development venture between Plaintiff and Intel; (c) Alternatively, Intel was under an implied obligation of confidentiality in respect of the venture and sale; and (d) Joint venture to develop CMP pad created a special relationship between Plaintiff and Intel, and an obligation of confidentiality owed by Intel to the Plaintiff.
In considering the question of whether Intel owed the Plaintiff an express obligation of confidence, the High Court held that it was unable to recognise the existence of any express confidentiality undertaking or agreement providing for an obligation of confidence in respect of the “IC-1000” pads sold to Intel, on the basis of the available evidence.
In considering the question of whether Intel owed the Plaintiff an implied obligation of confidence, the High Court held that considering all circumstances of the disclosure, there was an implied obligation of confidence between the Plaintiff and Intel. It was clear that information of commercial or industrial value was being given on a business-like basis and with a common object in mind. At the very least, there was a “project” between Intel and the Plaintiff, which provides a useful starting point to suggest that Intel was most likely bound by an obligation of confidence. In applying the relevant test, the High Court found that a reasonable man standing in Intel’s shoes would have realised that the information was being given to him in confidence for the following reasons:
- Nature of the information communicated: The “IC-1000” pads were experimental in nature. Given that these experimental pads were developed over a period of testing with different microelements and pre-polymers, information communicated to Intel did in fact have a “necessary quality of confidence about it”. The Defendants themselves redacted the data of their own CMP Pads, which reinforces the notion that such data is likely highly confidential.
- Circumstances in which the information was communicated: On a balance of probabilities, the High Court found that the circumstances in which information was imparted here imported an obligation of confidence. Intel stored its “IC-1000” pads in its research facilities which were off-limits to outsiders. Presentations about the “IC-1000” pads were only made at a conference which was expressly stated to be “confidential”. Intel’s provision of its test data back to the Plaintiff, especially in light of its own description of the exchange as a “project”, amounts to a degree of cooperation between the two companies.
In considering whether the Sematech conference or the Plaintiff’s dealings with Sematech amounted to prior disclosure, the High Court found that regardless of whether any express confidentiality undertaking existed in respect of the “IC-1000 pads”, there was nevertheless an implied obligation of confidence. The Sematech Agreement envisioned the importance of confidentiality between the Plaintiff and Sematech. The Sematech conference programme sheet was expressly marked “Confidential”, and the slides of the conference presentations that were adduced into evidence did not appear to reveal information about the “IC-1000” pads that was of a confidential nature. Further, even if Sematech and the participants at the conference were not subject to obligations of confidentiality, and even if some information about the “IC-1000” pads was released at the conference, this did not necessarily mean there was prior disclosure. On the facts, information released was very broadly stated there was no enabling disclosure. As such, the High Court found that in any case, the Patent was not anticipated by the disclosure of any information to Sematech or to others at the Sematech conference.
In considering whether the brochure amounted to commercial disclosure of the “IC-1000” pads, the High Court found that it did not amount to such commercial disclosure. The High Court considered that the Brochure only described “IC” pads in general terms and did not mention what microelements were used in the pads. There was no evidence before the High Court on what the sample would disclose to the hypothetical skilled reader. Consequently, the High Court found no enabling disclosure on the facts.
In conclusion, the High Court held that any disclosures with regard the “IC-1000” pads and the Patent were made in confidential settings, and thus cannot be regarded as prior publications. In any event, any of the said disclosures were not sufficient to enable the hypothetical skilled reader to make the invention. Accordingly, the Patent was not anticipated by any prior use of the “IC-1000” pads, and the Defendant’s challenge against the novelty of the Patent was dismissed.
The legal principles
Section 13(1)(b) of the Patents Act provides that the invention must involve an inventive step. Section 15 defines an inventive step as one that “is not obvious to a person skilled in the art”, having regard to any matter which forms part of the state of the art by virtue only of matters made available to the public and without having regard to matters from patent applications with earlier priority dates but published later than the priority date of the invention.
The relevant four-step test (“Windsurfing test”) provides: (a) Identify the inventive concept embodied in the patent in suit; (b) Court assumes mantle of the normally skilled but unimaginative addressee in the art at the priority date, imputing to him what was, at that date, common general knowledge in the art in question; (c) Identify what, if any, differences exist between the matter cited as being “known or used” and the alleged invention; (d) Court then asks itself the question whether, viewed without any knowledge of the alleged invention, those differences constitute steps which would have been obvious to the skilled man or whether they require any degree of invention.
Making a “mosaic” out of the prior art is permissible for the purposes of showing that an invention lacks an inventive step, as long as the mosaic can be put together by an unimaginative man with no inventive capacity.
(2) Inventive Concept of the Patent
Applying the first step of the Windsurfing test, the High Court found that the inventive concept to be the incorporation of hollow, flexible, organic polymeric microelements in the work surface and the subsurface, which allows for the regeneration of the work surface. It lies essentially in the use of a hollow, flexible, organic, polymeric microelements in a CMP pad.
(3) The skilled addressee with common general knowledge in the art
Applying the second step of the Windsurfing test, and bearing in mind the general rule that the skilled addressee “should be taken to be the workman or technician who is aware of everything encompassed in the state of the art and who has the skill to make routine workshop developments, but not to exercise inventive ingenuity or think laterally”, the High Court found that the skilled reader in this case is someone who has a degree in chemical, mechanical or materials engineering or in physics or chemistry, and with about three years’ work experience with CMP processes. It also agreed with the Plaintiff that the skilled person should be someone active in or otherwise familiar with CMP manufacturing around the priority date, or otherwise imputed with the common general knowledge in the art at the relevant time.
(4) Differences between the state of the art and the invention, and obviousness
Applying the third and fourth steps of the Windsurfing test, the High Court decided that the invention in question would not be obvious to the skilled addressee in respect of various pieces of prior art identified by the Defendants because:
- With respect to the Japanese Patent, which was asserted by the Defendant to be the closest prior art to the invention, the High Court found that there were in fact appreciable differences between the Patent and the Japanese Patent. The most notable differences were that none of the examples of microelements mentioned in the Japanese Patent have all the features of a “flexible”, “polymeric”, “hollow” and “organic” microelement. The need for regular scraping of the pad to regenerate the surface was also underscored in the Japanese Patent, whereas in contrast, the Patent provides that as the work surface of the pad wears, the subsurface immediately below becomes the new work surface and the two levels of hardness are maintained and regenerated continuously. Taking these differences into account, the High Court found that the inventive concept would not have been obvious to the skilled person on the basis of the Japanese Patent alone.
- With respect to the Robie Patent, the Defendants’ case was that it would be obvious to the skilled person to combine the invention in the Japanese Patent with the concept of using thin-walled balloon-like bodies as disclosed in the Robie Patent. The High Court found that while the alternative of using balloon-like particles may disclose or suggest the concept of using hollow organic microelements, it was nevertheless not clear that the Robie Patent taught the concept of using microelements that are hollow, flexible and polymeric. Even when mosaicked with the Japanese Patent, the High Court considered that the unimaginative skilled reader would not infer from the Robie Patent all of the four said qualities of the microelements used in the Plaintiff’s Patent. Some degree of inventiveness beyond what the notional skilled person possesses would be required to mosaic the relevant parts of the Japanese Patent and the Robie Patent together in the first place.
- With respect to the Akzo Nobel Publications, the Defendants argued that by mosaicking the Japanese Patent and the Akzo Nobel Publications together, it would have been obvious to the skilled reader to incorporate the ready-made “Expancel” microelements into the existing pads. The High Court found that no prior art explains how exactly “Expancel” microspheres could be incorporated into a CMP pad. Also, whilst the Akzo Novel Publications referred to a range of potential uses such as for soles of running shoes, car body filler etc., there was nothing to suggest that “Expancel” was being put forward for use in CMP pads or semiconductor products.
In conclusion, the High Court found that even if the skilled reader had all the prior art disclosures cited against inventive step before him, there was no obvious mosaic that would lead to the invention as claimed. On the evidence, the High Court also found that the skilled person would not have found it obvious to adapt the cross-linked polymer material disclosed in the Japanese Patent so as to take the form of micro-balloons (hollow, flexible and polymeric), instead of tiny fragments of a cured sheet, in order to reduce scratching and surface defects of the work piece. Hence, the invention in the patent would not have been obvious to the skilled reader in 1992.
The legal principles
Section 80(1)(c) of the Patents Act provides that a patent may be revoked if its specification “does not disclose the invention clearly and completely for it to be performed by a person skilled in the art”.
While the patent specification must be “clear and complete”, it “need not set out every detail necessary for the performance of the invention, but can leave the skilled man to use his skill to perform the invention”. The sufficiency requirement is met if the skilled person can carry into effect or work the invention without making further inventions or engaging in a prolonged study of the matter. This is so even if the skilled person ahs to engage in some trial or experiment in the process of working the invention.
Whether the Patent meets the requirements of sufficiency
Given that this area involved semiconductor wafers and related processes, the High Court considered that any patent specification would reasonably require a higher degree of precision.
However, the High Court found that in respect of the matters of which the Defendants made complaint as being insufficient, vague and imprecise, i.e. work surface, subsurface, relative hardness or softness and flexibility, the objection had not been established on the evidence and a reading of the specifications and claims.
In summary, the High Court found that there were no grounds on which the Patent could be invalidated or revoked. The High Court found that the Patent was valid, and dismissed the Defendants’ prayers for a declaration of invalidity and an order for revocation.
Issue 2: Infringement
The Defendants’ case was that their actions did not infringe the Patent, even if the Patent was found valid.
Whether new, as-received and unconditioned pads can fall within the asserted claims
The Defendant’s primary submission was that the NexPlanar pads they dealt with were new, as-received and unconditioned pads which did not fall within the scope of the asserted claims, which only covered conditioned or “broken-in” pads.
On a purposive interpretation of the claims, the High Court was of the view that the term “work surface” in the claims did not necessitate that the pad be in use, conditioned or broken-in for it to fall within the claim. While much of the claims and descriptions in the specifications go into detail about what happens when the work surface comes into contact with the working environment, this did not mean that the Patent was intended to be limited in this regard. The High Court considered that it would be artificial to limit the coverage of the claims only to used or conditioned pads, as it would very well defeat the purpose of obtaining patent protection in the first place if new pads were excluded. As a matter of common Sense, the skilled addressee would not understand the patentee to be only referring to a used or a conditioned pad by the language in the relevant claim.
As such, it was held that new and unused pads were not precluded from falling within the relevant claim.
- Whether the three tested NexPlanar Pads infringed the asserted claims
The question here was whether the NexPlanar Pads did in fact infringe the asserted claims. The High Court considered the Independent Assessor’s Report, and noted that there appeared to be no dispute as to the independent assessor’s findings that the facts sought to be proved by the Plaintiff in respect of dependent claims had in fact been satisfactorily made out. The High Court held that upon the proper construction of the terms “work surface” and “texturized work surface”, the findings in the said report indicate that all the components of the asserted claims were present in the tested NexPlanar Pads.
Whether the remaining nine untested NexPlanar Pads infringed the asserted claims
Only three NexPlanar Pads were tested, but the Plaintiff’s infringement claim was in respect of 12 NexPlanar Pads in total. No tests were performed in respect of the other 9 pads, and no explanation was proffered during the parties’ submissions as to why this was the case. The High Court held that the Plaintiff had not discharged its burden of proving that the 9 untested pads infringed the Patent, and hence dismissed any claims of infringement with regard to the 9 untested pads.
Whether the Defendants’ actions amount to infringement of the NexPlanar Pads
The High Court held that it was clear that the Defendants’ acts amounted to the disposal, importation and/or keeping of a patented product without the consent of the patentee, and therefore there was infringement. As for the 1st Defendant, the claim was that they disposed or offered to dispose the infringing pads to the 2nd Defendant in Singapore. The High Court noted that while there was limited evidence as to where the acts or offers of disposal took place, there was certainly evidence that the 1st Defendant’s technicians came to Singapore to meet with representatives of the 2nd Defendant as well as representatives of the 2nd Defendant’s customers such as United Microelectronics. Even if this was not a sufficient basis to find that the 1st Defendant disposed of the infringing pads or made the offers of disposal in Singapore, the High Court also found that the 1st Defendant was in any case liable as a joint tortfeasor with the 2nd Defendant.
Whether the Defendants may be regarded as joint tortfeasors
The doctrine of joint tortfeasorship has been recognised in Singapore law, and can be divided into 2 broad categories: (a) where one party conspires with the primary party or induces the commission of the tort; or (b) where two or more persons join in a common design pursuant to which the tort is committed. The Plaintiff mainly relied on the latter category of “common design”, contending that the Defendants acted in concert and in furtherance of the infringement pursuant to a common design, and may therefore be regarded as joint tortfeasors. The High Court noted that the finding of joint tortfeasorship by common design “requires the discharge of a heavy evidentiary burden on the part of the plaintiff”, and that the threshold for such a finding is a high one. The joint tortfeasors must have been” so involved in the commission of the tort as to make himself liable for the tort”.
The Defendants argued that the relationship between them was merely that of a buyer and seller, and that this was insufficient to establish a common design such as would support the conclusion of joint tortfeasorship.
However, the High Court held that the evidence suggested otherwise:
- Evidence suggested that the 1st Defendant was more than a mere” passive” seller to the 2nd Defendant, as it was clearly involved in the 2nd Defendant’s sale of the NexPlanar Pads to customers such as United Microelectronic;
- 1st Defendant knew that the NexPlanar Pads would be sold to United Microelectronics. Plaintiff had presented evidence showing that the 1st Defendant communicated and dealt with customers such as United Microelectronic directly;
- Plaintiff adduced an e-mail from 1st Defendant’s technical marketing manager to the 2nd Defendant’s representatives, which showed that the 1st Defendant was aware that it was providing samples for evaluation by United Microelectronics.
As such, the High Court found that the Plaintiff had proven the 1st Defendant was not merely acting as supplier of the infringing pads, but also made the 2nd Defendant’s infringing acts its own. The defendants may therefore be regarded as joint tortfeasors in that they have acted in concert and in furtherance of the infringement pursuant to a common design to sell the infringing pads to United Microelectronic.
Issue 3: Remedies for infringement
In summary, the Patent was found valid prior to its expiry. The asserted claims of the Patent were found infringed by the Defendants’ actions, but only in respect of the three tested NexPlanar Pads, i.e. “NEXX-09V1”, “NEX4-6035-30S” and “E7980-30S-25-70TS-4CF”. A declaration of the Patent’s validity was granted to the Plaintiff, along with a declaration that the asserted claims were infringed by the Defendants. The Defendants’ counterclaims were dismissed in their entirety.
However, the High Court saw no reason to grant any injunctions sought by the Plaintiff since the Patent had already expired. As the trial was bifurcated and proceeded on liability only, the issue of damages and/or account of profits would be assessed separately (not in this judgment).
In this case, parties had also submitted on the reliability of expert witnesses, i.e. 2 called on by the Plaintiff and 1 called on by the Defendant. Unsurprisingly, each party had attempted to cast doubt on the expertise and/or neutrality of the other side’s expert witnesses. In this regard, George Wei J set out helpful guidelines and explanations on the role of an expert in legal proceedings involving patent law in this case. Importantly, he clarified that “an expert is not an advocate for the party retaining him, and his advocacy is limited to supporting his independent views and not his client’s cause”. The Rules of Court expressly provides that the expert’s duty to the court “overrides any obligation” to his client. As such, the expert must “remain detached from the fray” and should not have any interest in the outcome of the proceedings nor partiality to the facts in issue.
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This article is written by Renee Xavier from Alpha & Omega.
This legal update was originally published on Alpha and Omega’s website.
This article does not constitute legal advice or a legal opinion on any matter discussed and, accordingly, it should not be relied upon. It should not be regarded as a comprehensive statement of the law and practice in this area. If you require any advice or information, please speak to a practicing lawyer in your jurisdiction. No individual who is a member, partner, shareholder or consultant of, in or to any constituent part of Interstellar Group Pte. Ltd. accepts or assumes responsibility, or has any liability, to any person in respect of this article.