The first silicon hairspring was presented by Ulysse Nardin thanks to Sigatec, a joint venture with Mimotec, which specializes in silicon micro-components. The brand has developed a unique expertise in the field. On the other hand, Rolex, Patek Philippe and the Swatch Group collaborated in a joint development with CSEM. They patented the technology which was the reason of a dispute with Sigatec. watchesreplica.is www.replicawatches.to An agreement between all parties was found (although its terms were not disclosed in 2013).