The ISEQ continues to struggle after last week's uncertainty following the Madrid bombing.
It finished down 26.20 points to close at 5067.00.
Dermot Desmond was in the news again as his investment vehicle IIU all but put paid to Tony Mullins management buy out plans at Barlo.
Desmond now owns just over 19% of the plastics and radiators group before the company's extraordinary general meeting next Tuesday, March 23.
The share price remains on 42c.
Rumours that Desmond may bid for Datalex also reached the market.
Shares in the company closed up 2c to €0.62.
Tullow Oil announced that production has begun in the Boulton H Well gas field in the southern North Sea.
Shares in the company advanced 5c to close at €1.60 on the news.
Financials saw AIB down 5c to €12.06, Anglo Irish down 26c €12.94 while BOI was down 11c to €10.17.
Ryanair was down 5c to €4.60 ahead of the threatened industrial dispute at Dublin airport.
Weekend media reports said that Germanwings and BMIBaby are to co-operate in order to compete with Ryanair.
The low-fares airline already faces major disruption to schedules on Thursday as Dublin airport may be forced to close.
Chief Executive Michael O'Leary said it may try to divert some aircraft to Baldonnel Airport, Co Dublin and called on Aer Rianta to implement a contingency plan to keep the capital's airport open.
Independent News and Media was down 1c to €2.03 despite its 'Independent' title in the UK showing sales up 15.2% year-on-year.
This has been attributed to the paper's launch of a tabloid-size edition.
Paddy Power were up 10c to €8.50 ahead of the beginning of Cheltenham Festival, the highlight of the National Hunt horseracing calendar.