His death is believed to be the result of a dispute between the convicted men and the Somalian gang the victim was associated with, known as the Centric gang or Centric boys.
Up to 40 men were involved in the attack, during which they shouted "Stab him through the heart, stab him dead through the heart".
Ismail Mohamed, 20, of Beresford Road, Haringey; Liban Elmi, 20, of James Gardens, Wood Green; and a 17-year-old youth were today found guilty of his murder.
A further five people aged between 16 and 25 were cleared of murder charges but found guilty of charges including conspiracy to wound to commit grievous bodily harm and violent disorder, and conspiracy to possess offensive weapons.
During the attack Osman was stabbed more than 20 times. Earlier in the evening the group were seen arming themselves with bottles, knives, hammers and pieces of wood.
After the attack the gang attempted to run away onboard a number 253 doubledecker bus, which was eventually stopped by police and 24 suspects were arrested.
Commenting on the case, Detective Chief Inspector Michael Broster, the senior investigating officer of the Specialist Crime Directorate, said: "This group of men went to Camden with the sole intention of attacking anyone belonging to the opposing group. It was a premeditated attack using a level of violence I have rarely seen.
"This has been a complicated case to piece together due to various factors such as the time of night and the speed of the attack."
He added that the convictions bring Mr Osman's family the "justice they deserve".
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