Europe's highest court has kept alive an appeal by micro-processor giant Intel against a €1.06 billion fine for alleged anti-competitive behaviour.
The European Court of Justice set aside an earlier judgment by a lower court which had dismissed Intel's appeal against the fine.
Intel was originally hit with a record €1.06bn fine imposed by the European Commission in May 2009 for having abused its dominant position in the processor market.
The commission had said Intel had offered its clients price rebates to use its computer chips in preference to those of rival Advanced Micro Devices (AMD).
The US tech giant, which has its European manufacturing headquarters in Leixlip, Co Kildare, appealed the fine to the General Court in Luxembourg.
In 2014 the General Court dismissed the appeal.
Intel then appealed that decision to the highest court, the European Court of Justice.
This morning the court kept the appeal against the fine alive by sending it back to the General Court.
The General Court has been asked to further explore how Intel's customer rebates may have restricted competition.
The commission had originally claimed that Intel abused its dominant position on the worldwide market for so-called x86 Central Processing Units (CPUs) from October 2002 to December 2007.
The company had allegedly done this by trying to force AMD out of the micro-processor market.
The commission said Intel had given rebates to four major computer manufacturers - Dell, Lenovo, HP and NEC - on the condition that they purchased from Intel all, or almost all, of their x86 CPUs.
Intel also awarded payments to the electronics retail group Media-Saturn in order that the group would sell only those computers containing Intel's x86 CPUs.
The European Commission claimed that those inducements significantly diminished the ability of Intel's competitors to compete on the merits of their processors, thus reducing consumer choice and lowering incentives to innovate.
The ECJ ruled that the lower court had failed to fully examine all of Intel's arguments over the methods by which the commission had concluded that Intel's rivals were indeed being frozen out of the market.
The decision is the latest stage in a long running sage between Intel and the EU.
The outcome could have major implications for similar anti-trust cases that have been taken against other tech giants such as Google and Qualcomm.
In June the commission hit Google with a €2.4bn fine over its online shopping services.