Supreme Court success for Brinkhof and Cooler Master over cooling systems

Danish company Asetek holds European patent EP 1 923 771 B1, filed in November 2004, which covers a technology for cooling systems for computers. In 2017, Asetek sued Taiwanese computer hardware manufacturer Cooler Master for infringement of its patent EP 771. Cooler Master successfully counterclaimed for invalidity of the Dutch part of EP 772. Now the Supreme Court in the Netherlands has upheld the judgment.

Cooler Master counterclaims

Asetek’s patent EP 771 contains two product claims. Firstly, claim 1 covers computer cooling system components including liquid reservoirs and reservoir housing, a heat radiator, a pump and a heat exchanger. The claim also specifies an impeller – the rotating part of a pump or compressor – positioned separately to the liquid reservoir channels. Claim 2 specifies that the liquid reservoir components set out in claim 1 have a rough, or non-smooth, inner wall surface.

Furthermore, EP 771 relies on the priority of US patent 517924 P, dated 07 November 2003. In its counterclaim for infringement, Cooler Master argued that EP 771 is not entitled to the above priority of the US patent. The company argues that a 2004 Chinese utility model CN 2610125Y, known as Lin, is in fact state of the art, and also that claim 2 is invalid.

Invalid for inventiveness

Based on Article 87 of the European Patent Convention, the District Court of the Hague  argued the priority date for the US patent was invalid. Furthermore, the court also decided that claim 1 is not novel over Lin. It also decided that claim 2 of EP 771 is invalid. Thus, the first-instance court found the Dutch part of EP 771 invalid.

In May 2019, the Court of Appeal of The Hague upheld the first instance decision. Asetek then appealed the judgment to the Supreme Court of the Netherlands. However, in December 2020 the Supreme Court dismissed the appeal and ordered Asetek to pay the cost of proceedings.

The Netherlands and Germany have also seen further litigation on EP 771, although not against Cooler Master. In September 2017, the Dutch courts stayed the case against German company Coolergiant, pending the outcome of the case against Cooler Master. Proceedings are also pending on the same patent in Germany against Coolergiant.

Paul Reeskamp

At the Supreme Court

A team from DLA Piper’s Amsterdam office, led by partner Paul Reeskamp, acted for Asetek in the first- and second-instance proceedings, as well as preparing the arguments for the Supreme Court. In the Netherlands only lawyers admitted to the Supreme Court of the Netherlands bar can appear on behalf of clients.

As such, DLA Piper instructed Thijs van Aerde of independent full-service firm Houthoff to appear at the Supreme Court.

Asetek has instructed DLA Piper on this case since January 2016, after Paul Reeskamp and Marijn van der Wal joined the firm. DLA Piper had begun working with Asetek on other issues in 2015.

Similarly, IP boutique firm Brinkhof acted for Cooler Master throughout the proceedings, although partner Jan Pot led the case in front of the Supreme Court. Jan Pot is the only Brinkhof patent lawyer registered with the Supreme Court of the Netherlands bar.

Rien Broekstra

However, prior to the final hearing, partner Rien Broekstra led proceedings before the District Court and the Court of Appeal. Brinkhof obtained Cooler Master as a client in 2016, before proceedings against Asetek began.

For Cooler Master
Brinkhof (Amsterdam): Rien Broekstra, Daan de Lange, Jan Pot (Supreme Court bar) (all partners)
De Vries & Metman (Arnhem): Hendrik Jan Zonneveld (patent attorney)

For Asetek
Houthoff (Amsterdam): Thijs van Aerde (Supreme Court bar)
DLA Piper (Amsterdam): Paul Reeskamp (partner); associates: Marijn van der Wal, Ruben Verweij
V.O. (Amsterdam): Bernard Ledeboer (patent attorney)

Supreme Court of the Netherlands, Civil Room, no.19/03825
Martijn Polak (chairman and counsel), Tanja Tanja-van den Broek, Maarten Kroeze, Carla Sieburgh, Pieter Frans Lock