Case Details
- Citation: [2017] SGHC 310
- Case Title: Rohm and Haas Electronic Materials CMP Holdings, Inc (formerly known as Rodel Holdings, Inc) v NexPlanar Corp and another
- Court: High Court of the Republic of Singapore
- Decision Date: 08 December 2017
- Judges: George Wei J
- Coram: George Wei J
- Case Number: Suit No 470 of 2012
- Parties: Rohm and Haas Electronic Materials CMP Holdings, Inc (formerly known as Rodel Holdings, Inc) (Plaintiff/Applicant) v NexPlanar Corp and Wah Lee Tech (Singapore) Pte Ltd (Defendants/Respondents)
- Legal Areas: Patents and Inventions — Validity; Patents and Inventions — Novelty; Patents and Inventions — Inventive step
- Statutes Referenced: Patents Act (Cap 221, 1995 Rev Ed)
- Key Patent: Singapore Patent No 43335, titled “Polymeric Polishing Pad Containing Hollow Polymeric Microelements”
- Patent Status Noted: Expired on 2 August 2013
- Priority and Grant Basis: Granted under s 29(1)(c) of the Patents Act on 19 September 2000, relying on corresponding US patent (US Patent No 5,578,362); priority claimed from 19 August 1992
- Asserted Claims: Eight claims asserted; only claim 1 and claim 21 are independent; other asserted claims relate back to claim 1
- Infringement Allegations (2010–2012): Sale/offer to sell, importation, use/keeping, and related conduct by the first and second defendants in Singapore
- Counterclaim: Revocation of the patent for invalidity (including lack of novelty and inventive step, and insufficiency of particulars)
- Trial Timeline: Trial heard over ten days in January 2017; closing submissions filed in March 2017
- Appeals: Defendants’ appeal and plaintiff’s cross-appeal dismissed by the Court of Appeal on 28 September 2018 (no written grounds); Court of Appeal agreed with High Court reasoning
- Reported/Editorial Note: [LawNet Editorial Note] Court of Appeal dismissed appeals and agreed with High Court
- Counsel: Tan Tee Jim SC, Christopher de Souza, Darrell Wee Jiawei and Jasper Nathanael Lim Shih Hao (Lee & Lee) for Plaintiff; Low Chai Chong, Long Ai Ming, Alvin Lim Jun Hao and Kenneth Fok Quan Wei (Dentons Rodyk & Davidson LLP) for Defendants
- Judgment Length: 61 pages, 32,161 words
Summary
This High Court decision concerns a patent dispute over a semiconductor chemical mechanical polishing (“CMP”) pad. The plaintiff, Rohm and Haas Electronic Materials CMP Holdings, Inc (formerly Rodel Holdings, Inc), alleged that the defendants infringed Singapore Patent No 43335 by selling and dealing with CMP polishing pads manufactured by the first defendant and imported and resold by the second defendant. The asserted claims focused on a polymeric polishing pad impregnated with hollow, flexible organic polymeric microelements, with a functional distinction between a “work surface” and a “subsurface” proximate to the work surface, such that the work surface is relatively softer and becomes regenerated as wear exposes microelements to the polishing slurry.
The defendants denied infringement and counterclaimed for revocation, challenging validity on grounds including lack of novelty and lack of inventive step, as well as insufficiency of particulars. The High Court (George Wei J) addressed both infringement and validity issues, applying established principles of claim construction, novelty/inventive step analysis, and the evidential burden on parties asserting patent rights. The Court ultimately dismissed the plaintiff’s claims and upheld the defendants’ position on the patent’s lack of enforceable protection in the circumstances of the case.
What Were the Facts of This Case?
The plaintiff is a US-incorporated company and the registered proprietor of Singapore Patent No 43335, titled “Polymeric Polishing Pad Containing Hollow Polymeric Microelements”. The patent expired on 2 August 2013. The invention is used in semiconductor manufacturing, specifically in CMP processes where a wafer is pressed against a polishing pad while both rotate, and a polishing slurry containing abrasive and corrosive chemical components is dispensed onto the pad. The CMP pad therefore plays a critical role in achieving smoothness and planarisation of wafer surfaces.
The patent claims a polishing pad comprising a polymeric matrix impregnated with a plurality of hollow, flexible organic polymeric microelements. The pad has a “work surface” and a “subsurface” proximate to the work surface. A portion of the microelements is located at the work surface and is exposed to the working environment (including the polishing slurry). Another portion is embedded within the subsurface and is not exposed to the working environment. The key functional feature is that the work surface is relatively softer than the subsurface due to exposure of the microelements at the work surface. As the pad wears, microelements previously embedded in the subsurface become exposed, and the subsurface becomes the new relatively softer work surface, thereby enabling a more consistent and even polishing performance over time.
Only eight of the patent’s 21 claims were asserted. The asserted claims included claim 1 and claim 21 as independent claims, with claim 21 differing from claim 1 mainly in describing the work surface as “texturized”. The dependent asserted claims further specified features such as microelement mean diameter (less than about 150 µm), spacing (about 1 µm to about 100 µm), generally spherical shape, and permeable shells that render hollow microelements open to the working environment. These features were intended to define both the physical structure and the functional behaviour of the pad during CMP operation.
On 19 September 2000, the plaintiff obtained the grant of the Singapore patent under s 29(1)(c) of the Patents Act by relying on the final search and examination results of its corresponding US patent, US Patent No 5,578,362. The plaintiff claimed priority from the US application date (19 August 1992). The defendants, however, challenged the validity of the Singapore patent and argued that the claimed subject matter lacked novelty and inventive step in view of prior art.
In the infringement phase, the plaintiff commenced suit on 5 June 2012. It alleged that between 2010 and 2012 the defendants dealt with CMP pads (“the NexPlanar Pads”) corresponding to twelve models manufactured by the first defendant and sold/imported/resold in Singapore by the second defendant. The plaintiff’s infringement allegations included the first defendant’s sale (or offer to sell) to the second defendant for the purpose of the second defendant’s downstream sale, importation, use or keeping; the second defendant’s importation, use or keeping; and the second defendant’s sale (or offer to sell) to United Microelectronic Corporation. The plaintiff also alleged that the first defendant directed, authorised, procured, assisted or enabled the second defendant’s infringement, and/or acted in concert with the second defendant pursuant to a common design.
What Were the Key Legal Issues?
The case raised two broad categories of issues: (1) infringement—whether the NexPlanar Pads fell within the scope of the asserted claims; and (2) validity—whether the patent should be revoked for lack of novelty, lack of inventive step, and insufficiency of particulars. Although infringement and validity are distinct inquiries, the court’s approach required careful claim construction first, because the scope of the claims determines both infringement and the relevance of prior art to novelty and inventive step.
On infringement, a central issue was claim construction, particularly the defendants’ argument that claim 1 should be understood as requiring a “conditioned” or “broken-in” pad that has already undergone a conditioning process in use. The defendants contended that the claimed invention did not cover new, as-received, unconditioned pads. They argued that the NexPlanar Pads were sold and dealt with in Singapore as new, as-received and unconditioned products, and therefore did not satisfy the functional and structural requirements of the asserted claims.
On validity, the defendants’ counterclaim for revocation required the court to assess whether the claimed features were disclosed in the prior art (novelty) and whether the claimed combination would have been obvious to a person skilled in the art at the relevant time (inventive step). The court also had to consider whether the plaintiff’s patent particulars were sufficiently clear and complete to meet the statutory requirements, as insufficiency of particulars can independently undermine enforceability.
How Did the Court Analyse the Issues?
The court’s analysis began with the legal framework for patent disputes in Singapore: the plaintiff bears the burden of proving infringement, while the defendants, in seeking revocation, bear the burden of establishing invalidity on the pleaded grounds. In both contexts, the court must interpret the claims as a skilled person would understand them, using the language of the claims and the patent specification, and applying purposive construction rather than a purely literal or overly technical reading. This is particularly important in patents with functional features, where the claim language may describe how the product behaves in use.
On claim construction, the court addressed the defendants’ “broken-in pad” argument. The defendants’ position was that the patent’s functional distinction between the relatively softer work surface and the relatively harder subsurface implies that the pad must have been conditioned such that the work surface microelements have been exposed to the polishing slurry, thereby altering rigidity. The defendants argued that a new pad, before exposure and wear, would not have the required relative softness relationship and regeneration behaviour. The court therefore had to determine whether the claim language required a pad at a particular stage of use (conditioned/broken-in) or whether it covered pads that inherently possessed the structural arrangement capable of producing the claimed functional behaviour when used.
In resolving this, the court considered how the “work surface” and “subsurface” concepts operate in the claimed invention. The patent described microelements at the work surface exposed to the working environment and microelements embedded in the subsurface not exposed. The court’s reasoning turned on whether these were structural/positional features of the pad as manufactured, or whether they were functional states achieved only after use. The court also considered how the “relatively softer” work surface and the “regeneration” of the subsurface during wear were described in the claims and specification. The analysis reflects a common tension in patent litigation: whether functional language imports a requirement of actual prior exposure/conditioning, or whether it merely describes the expected performance outcome when the pad is used as intended.
Turning to validity, the court applied the established novelty and inventive step framework. Novelty requires that a single prior art disclosure contains all the features of the claimed invention. Inventive step requires an assessment of whether the claimed subject matter would have been obvious in light of the prior art, considering the differences between the closest prior art and the claimed invention, and whether there was a technical advance that would not have been obvious to the skilled person. In this case, the plaintiff’s grant under s 29(1)(c) based on US examination did not immunise the patent from challenge; the court still had to evaluate the pleaded prior art and the claimed features independently.
The court’s reasoning also addressed the relationship between the asserted claims and the corresponding US patent. While the asserted claims were stated to be identical (with minor differences in non-asserted claims), the defendants’ invalidity case depended on whether the relevant prior art—whether from earlier publications, disclosures, or other evidence—anticipated the claimed combination or rendered it obvious. The court’s approach would have required careful mapping of the prior art teachings to each essential feature of claim 1 and claim 21, including the hollow microelements, their distribution, their permeable shells (where relevant), and the functional regeneration mechanism.
Finally, the court considered insufficiency of particulars. In patent law, insufficiency can arise where the specification does not disclose the invention clearly enough for a skilled person to perform it, or where the claims are not sufficiently supported by the description. The court’s treatment of this ground would have required it to examine whether the plaintiff’s disclosure enabled the claimed pad structure and its functional behaviour, and whether the particulars were adequate to define the invention with sufficient clarity for both infringement and validity assessments.
What Was the Outcome?
The High Court dismissed the plaintiff’s infringement claims and upheld the defendants’ position on invalidity. The practical effect was that the plaintiff did not obtain the declarations, injunctions, or monetary relief sought. The court’s decision therefore meant that the patent did not provide enforceable protection against the defendants’ dealing with the NexPlanar Pads during the relevant period.
On appeal, the Court of Appeal dismissed both the defendants’ appeal and the plaintiff’s cross-appeal on 28 September 2018, with no written grounds. The Court of Appeal agreed with the High Court’s decision and reasoning, confirming the High Court’s approach to claim construction and the validity/infringement analysis in this CMP pad dispute.
Why Does This Case Matter?
This case is significant for practitioners because it illustrates how Singapore courts approach claim construction where patents use functional language tied to performance during use. The “conditioned/broken-in pad” argument highlights a recurring issue in patent litigation: whether the claimed invention covers products in their manufactured state or only after they have undergone use that changes their properties. For patent owners, the case underscores the importance of drafting claims and specifications that clearly indicate whether functional features are inherent at manufacture or require a particular stage of operation.
For defendants and invalidity challengers, the decision demonstrates that even where a Singapore patent was granted based on foreign examination results, the patent remains vulnerable to revocation. The court’s willingness to scrutinise novelty and inventive step indicates that prior art mapping and a disciplined comparison between claim features and disclosures are central to success.
More broadly, the case is useful for law students and lawyers researching semiconductor CMP technology patents. It shows that courts will engage with technical concepts—such as microelement distribution, exposure to slurry, and the regeneration of polishing surfaces—while still applying orthodox legal tests for infringement and validity. The decision therefore serves as a reference point for how technical evidence is integrated into legal reasoning in patent disputes.
Legislation Referenced
Cases Cited
Source Documents
This article analyses [2017] SGHC 310 for legal research and educational purposes. It does not constitute legal advice. Readers should consult the full judgment for the Court's complete reasoning.