Nasdaq OMX Group was recently in talks with private equity firm Carlyle Group to take the transatlantic exchange operator private, but the talks broke down due to price disagreements, according to a person familiar with the matter.

Carlyle initiated the discussions and was in early stages of due diligence, when disagreements emerged, bringing the talks to an end, a source familiar with the matter told Reuters on Monday.

The talks, first reported by Fox Business Network, were held about three weeks ago.

Nasdaq spokesman Joseph Christinat said the company does not comment on market rumors or speculation. A spokesman for Carlyle declined to comment.

Shares of Nasdaq were up 3.4 percent at $30.47 early on Monday afternoon.

(Reporting By John McCrank and Gregory Roumeliotis)