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George, Henry and John Sisk and family

The families of the Sisk brothers — George, 66, Henry, 64 and John, 62 — own a third each of Dublin-based Sicon, which doubled post-tax profit to £46m on turnover of £1 billion in 2005. Sicon is worth £190m and it spent £50m diversifying into the medical supplies sector last year. The families have received more than £50m in recent dividends and we add £32m for private assets.