Iverson, 38, hadn't played in the NBA for more than three years but said there were no regrets from a sometimes tumultuous NBA career that ran from 1996-2010.
"I thought once this day came, it would be basically a tragic day," Iverson said at a news conference. "I never imagined the day coming but I knew it would come.
"It is a happy day for me. I always thought this would be a tough day but it is a happy day."
Iverson was the No. 1 overall selection out of Georgetown by Philadelphia in the 1996 NBA draft. He was the league's Rookie of the Year the following season and was voted MVP in 2001 as he helped the 76ers to the NBA Finals.
He played a total of 12 seasons in Philadelphia, including his first 11 seasons in the NBA and a 25-game stint 2009-10 that turned out to be his last fling in the NBA. Iverson also played for Denver, Detroit and Memphis.
Iverson won league scoring titles in 1999, 2001, '02 and '05. He averaged 26.7 points a game over his 914-game career. His 24,368 points rank 19th in NBA history. He was selected to the All-Star Game 11 times.
"I don't have any (regrets)," Iverson said. "Would I change anything? No. My career was up and down at times. I made a lot of mistakes, a lot of things I'm not proud of ... I can't take any of it back."
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