Brexit: top Irish businessmen suffer €450m loss on Iseq

Brexit had wiped almost €450 million off the fortunes of well-known business figures behind four Irish Stock Exchange top-20 companies by the time the market closed on Monday.

Eugene Murtagh, founder and chairman of Kingspan, has seen the value of his 16.6 per cent holding in the Cavan-based insulation boards-making giant plunge by €201 million since the outcome of the UK referendum vote, as its market value dropped 27 per cent.

Analysts at Bank of America Merrill Lynch downgraded the stock on Monday to neutral from buy, while their earnings estimates and price target have also been cut as a result of the group's huge exposure to the UK and broader European market, where growth is expected to slow.

Ryanair chief executive Michael O'Leary saw the value of his 3.8 per cent stake in the low-cost carrier fall €158 million to €499 million last night from €657 million on Thursday. His company was worth €13.12 billion at close of business on Monday from a high of €17.34 billion on June 23rd.

Special dividends

Mr O’Leary’s stake means that he would have shared in the €400 million returned to shareholders last year following the sale of its stake in

Aer Lingus

, part of an overall €1.3 billion paid to investors in special dividends last year.

Paddy Power Betfair shareholder David Power, one of the group's founders, lost €62 million on his 4.1 per cent stake in the gambling giant. It was worth €333 million on Monday, compared with €395 million on Thursday.

The company is headquartered in the Republic, has its primary listing in London and a secondary listing in Dublin. Its overall value fell from €9.52 billion last Thursday to €8.04 billion on Monday.

The value of Irish Continental Group chief executive Eamonn Rothwell's 14.8 per cent stake in the ferries operator has fallen by €27 million as investors mulled the impact of Brexit on its business. A slump in sterling against the euro to a 31-year lows is seen impacting the number of British tourists to Ireland and this State's exports in the other direction.