The trade of Moss by Minnesota to Oakland, which was reported last week, became official Wednesday. He appeared at a news conference wearing his new No. 18 jersey.
That is the number he wore at Marshall when he was drafted by the Vikings, but switched to No. 84 while with the Vikings.
"I am very flattered to be here and anxious to be in this situation," Moss said. "I want to get back to being a dangerous player."
The Vikings received linebacker Napoleon Harris and two picks in this year's draft, one of them the seventh player overall. Minnesota also has its own first-round pick at No. 18.