A U.S. appeals court has struck down two of Conrad Black's convictions and upheld two others, all of which stem from the case that sent him to a Florida prison three years ago.

The appeals court had been mulling over Black's appeal for the past month, after prosecutors and his own lawyer made arguments before the three-judge panel.

On Friday, the court overturned two of Black's fraud convictions on a legal technicality -- that the "honest services" law used to convict him did not apply to those counts.

But the appeals court upheld two other convictions in the case that convicted the former media baron and some of his colleagues of defrauding Hollinger International investors in 2007.

The two convictions that were upheld against Black were for obstruction of justice and for fraud.

Black must now be resentenced on the charges that were upheld against him.

CTV's Paula Todd said the appeal court is upholding the obstruction charge on the basis that it still stands, regardless of the honest service ruling.

The appeals court also ruled to uphold one fraud charge because it was not related to the same honest services laws, Todd said.

The 66-year-old Black has been on bail for the past two months while waiting for the court to return a decision on his appeal.

Black had served more than two years in prison at the time he was granted bail.

With files from The Canadian Press