Independent News & Media (INM) has reclassified two of its directors as no longer being considered independent.
The development follows a review by consultancy group Deloitte.
The media group's largest shareholder is businessman Denis O'Brien.
More than half of the board is now deemed to be non-independent and therefore the group is in breach of a corporate governance code according to INM's annual report.
The company said: "INM is committed to high standards of corporate governance and will take actions to address this area of non-compliance in the next four months."
One director Triona Mullane provided consultancy services to INM through a company called Glenanaar Technologies Limited.
She is also CEO and Co-founder of mAdme Technologies Limited, which received an investment from a relation of Denis O'Brien.
While the INM annual report said Ms Mullane has always demonstrated independence at the board of INM, the company determined she should not be considered independent.
Another INM director Allan Marshall was also reclassified as a non-independent director.
Mr Marshall provided consultancy to INM through a company called ComputerCall, from which he received additional remuneration.
The company's annual report said he had demonstrated independence at board level but should not be considered independent.
In the annual report chairman Leslie Buckley said the company had established a formal review to inquire into matters concerning the "possible acquisition" of Newstalk.
He added INM had also been notified by the Office of the Director of Corporate Enforcement (ODCE) to produce certain records identified by the ODCE in relation to the proposed acquisition.
It said the company is taking appropriate steps to comply with the request. But he said this does not involve any conclusion that there had been a breach of corporate governance.