Copyright injunction proceedings stayed pending arbitration in the US

Plaintiffs seek an injunction and other relief arising from alleged infringement of the plaintiffs' copyright and/or design rights in a medical waste disposal system which is the subject of an EC trademark by the defendants - defendants' motion to stay the proceedings in favour of arbitration - application is brought pursuant to O 56, r 4(1) of the Rules of the Superior Courts, as amended, Article 8(1) of the UNCITRAL Model Law on International Commercial Arbitration, the Arbitration Act 2010 and/or under the inherent jurisdiction of the court - first named plaintiff and first named defendant companies registered in Ireland - common case that there are a number of agreements which affect the relationship of the parties to the proceedings - a manufacturing service and supply agreement was entered into in September 2013 between the first named plaintiff and the first named defendant - a clause of this agreement provided for in arbitration of disputes arising out of the contract - a letter of understanding was entered into in May 2015 between the first named plaintiff and the first named defendant whereby the provisions of the agreement dealing with intellectual property and confidentiality would survive any termination of the manufacturing agreement - reseller agreement entered into on 1st September, 2014 - rider agreement to reseller agreement was entered into on 8 September 2014 - further reseller agreement of 30th September 2014 postdates the manufacturing agreement - real issue is whether the complete agreement clause in the rider to the reseller agreement has the effect of supplanting the arbitration clause in the manufacturing agreement providing for an arbitration in Ireland and the authorised reseller agreement and the rider to this agreement which provided for arbitration in the USA - plaintiffs have failed to discharge the burden of proof in establishing that the arbitration clauses are null and void - reseller agreement of 1st September, 2014 and continuous supply agreement of 8th September, 2014 were signed by the parties on 9th and 10th March, 2015 respectively which was after the reseller agreement of 30th September, 2014 containing the complete agreement clause.