Pistorius was initially found guilty of culpable homicide, the appeal by the prosecution saw his conviction overturned and he was found guilty of murder.
Judge Thokozile Masipa, who handed down the initial conviction after accepting Pistorius's version of events that he had no intentions of killing Reeva Steenkamp and that he had been negligent, will formally postpone the sentencing.
The Supreme Court of Appeals found that Judge Masipa did not correctly apply the legal principle of dolus eventualis which is about whether Pistorius should have seen the possible outcome of his action when he shot through a locked door. The judges said that Pistorius must have foreseen that firing shots into the door could kill whoever was behind it.
Pistorius now faces a possible 15 years jail term which is a minimum sentence for murder.
