The victim of a vicious biker gang assault is keeping a stiff, and silent, upper lip as prosecutors go easy on his attackers.

Alexian Lien said nothing Saturday as he left his Manhattan home with his young daughter, who witnessed him being brutally beaten in the violent Sept. 29 attack.

Prosecutors said Friday they would lessen charges against 10 bikers involved in the senseless assault — because Lien is healing so well.

Bundled in a black winter coat and hat, Lien walked a short distance carrying two bags, one with a princess doll sticking out, as he and his daughter left the family’s Financial District building.

He ignored questions about the legal development before heading back into his home.

Lien was hauled out of his Range Rover and pummeled in front of his family on West 178th Street in the terrifying videotaped incident, which unfolded after Lien’s SUV bumped one of the bikers. The group swarmed the family car on the West Side Highway. Lien ran over one of the motorcyclists as he fled, causing serious injuries and prompting the bikers to chase him for 50 blocks.

Originally facing first-degree gang assault charges that could have landed them sentences of 25 years behind bars, the suspects could get only 15 years if convicted.