A court in Cairo has fined Islam Afifi, former editor-in-chief of Al-Dostour newspaper, LE10,000 for "libeling" and "defaming" Essam El-Erian, vice chairman of the Muslim Brotherhood's Freedom and Justice Party.
Afifi was also ordered to pay El-Erian compensation of LE10,000.
He was acquitted on charges of "threatening the general peace."
The charges were brought by El-Erian over a story published in Al-Dostour in June 2012 when Afifi was editor.
The story claimed El-Erian and Brotherhood second-in-command Khairat El-Shater had been involved in planning violence, including shooting protesters and hiring 'eye-snipers', to be unleashed if Mohamed Morsi had lost the presidential election runoff to Ahmed Shafiq.
Afifi is the second media figure to be sued by El-Erian.
In mid-May, a court fined television host Jihan Mansour LE10,000 for "insulting" and "defaming" El-Erian for comments made on her Sabahak Ya Masr ('Good Morning Egypt') show about alleged attacks on anti-government protesters by Brotherhood members. She also paid LE10,000 in compensation to El-Erian.
Mansour had earlier sued El-Erian for slander over an allegation that she had been paid to verbally attack the Islamist group. A court fined the Brotherhood leader LE15,000 and ordered him to pay LE1,000 to Mansour in compensation.
A number of journalists and media figures in Egypt have been investigated on charges of insulting the president, a move some perceive as attempts to intimidate critics.