New filings with the stock exchange show that he has lifted his holding in the company, which owns brands including Irish Ferries, to 21.65pc from slightly over 20pc.
He controls the stake directly and through his Rokeby Investments vehicle. Rokeby Investments is an Ireland-based company whose directors are Mr Rothwell and his wife, Clodagh Moreland.
The filing shows that he increased his holding on January 2.
His stake in the group is currently valued at €196m based on Irish Continental’s €905m market capitalisation.
Mr Rothwell (70) has gradually increased his holding in the company over more than a decade.
Eamonn Rothwell has been CEO of Irish Continental Group since 1992
In 2011, the former stockbroker owned almost 16pc of the group.
At that time, he said he had no intentions of launching a fresh takeover bid for the ferry company, having made efforts to do so between 2007 and 2009.
The first offer made by Mr Rothwell and management back then was trumped by a €561m offer from Moonduster, a consortium of what was then the Philip Lynch-led One51 investment group and Cork-based Doyle Shipping.
That lapsed and Moonduster and Mr Rothwell joined forces in late 2008 to table a fresh offer for the ferry group, but never got around to actually making an offer to shareholders.
The financial impact of this is a €10.4m increase in the value of the listed investments
Accounts filed for Rokeby Investments last week show that at the end of 2024 it had investments valued at €103.6m.
During 2024, the company purchased almost 1.2 million additional shares in Irish Continental at €5.40 each for a total consideration of just under €6.5m.
“Following the financial year end, the share price of the listed investment increased to €5.70 per share at September 11, 2025,” the accounts said.
“The financial impact of this for the company is a €10.4m increase in the value of the listed investments.
“The financial statements have not been adjusted for the increase in the share price.”
Shares in Irish Continental are currently trading at €6.06 and have climbed 15.6pc in the past year.
In the six months to the end of June last year, Irish Continental posted revenue of €310m and earnings before interest, tax, depreciation and amortisation of €55m.
The figures were 8.5pc and 10.5pc higher respectively year-on-year. Its operating profit was up 41pc, at €24.6m.
The group also owns the Eucon container and terminal business.