Bigger than Whoofter Botch's share of the Holland market.
I think you will find that Buderus, part of the Bosch Thermotechnic group,and Remeha are the market leaders in the Netherlands. Not Intergas.
http://www.delta-ee.com/delta-ee-bl...es-them-a-platform-to-grow-in-the-netherlands
Bosch Group hold one of the two largest shares in the UK boiler market. The other one is not Intergas, who are one of the minnows over here.
Which make your claims somewhat fanciful.
You can say Intergas make the best boilers, that is a personal view. Market Share is not, why make things up?