Unfortunately for them the High Court ruled that Hoover had intentionally copied the technology at the heart of Dyson's Dual Cyclone vacuum cleaner. Dyson said: “Their claims that the Triple Vortex is different were shown to be completely false. Hoover showed no interest in the technology when we were looking for backers. Then they rubbished it when we brought out the bagless cleaner, insisting that bags are best. Finally they came out with a blatant copy.