A housing and consumer economics major, Seymour was a four-year letterman at Georgia (1997-2000) who played in 41 games for the Bulldogs, starting 25. He finished his career with 223 tackles (106 solos), nine-and-a-half sacks, 25.5 tackles for losses and 35 quarterback pressures.
He was selected two times to the All-Southeastern Conference first-team (1999-2000). As a senior Seymour was named All-American first-team selection by the American Football Coaches Association and Walter Camp, and was selected by The Sporting News for their second team.
As a senior, Seymour started ten games at right defensive tackle, recording 78 tackles (35 solos) and a team-leading 10.5 tackles for loss, and 1-1/2 sacks plus 13 quarterback pressures. He earned SEC player of the week honors following his performance vs. the Tennessee Volunteers. In 1999, as a junior, Seymour started all 11 games at right defensive tackle and led the team with 74 tackles (38 solos), including 10 tackles-for-loss, 4 sacks and seven quarterback pressures. He also picked of a pass. Named SEC defensive player of the week for his performance against the South Carolina Gamecocks. In that contest he collected six tackles (5 solos), including a pair of sacks, three stops for minus 12 yards and a pressure that resulted in an interception in a 24-6 victory
Seymour appeared in every game in 1998 as a sophomore and made 4 starts. He finished fourth on the team with 69 tackles (32 solos) and had 4 sacks and 14 quarterback pressures. He also appeared in nine games during his 1997 freshman year at right defensive tackle and made two tackles and had a quarterback pressure.
He has been selected to five NFL Pro Bowls and three AP All-pro teams. His hallmark is his versatility, as he is capable of playing 4-3 defensive tackle, 4-3 defensive end, 3-4 defensive end, and 3-4 nose tackle all at a high level. He has gone to the Pro Bowl both as a 4-3 Defensive Tackle (DT) and a 3-4 Defensive End (DE). Seymour also occasionally plays fullback on short yardage and goal line situations. But hasn't seen work as a fullback since suffering a knee injury on a 1-yard Corey Dillon touchdown run vs. the Chargers in 2005.
Many have considered Seymour to be the best defensive lineman in the NFL. He has been described as the best #6 overall draft pick of all time.
In 2005 Seymour did not report to minicamp and missed the first four days of training camp because he was reportedly upset over his rookie contract, which had yet to expire and left him underpaid in his view. To induce Seymour to report the Patriots gave Seymour a $1 million raise in his 2005 salary. In April, 2006, Seymour signed a four-year $30 million contract extension which will keep him with the Patriots until 2010 unless released.
Seymour was fined $7,500 by the NFL for stepping on Colts lineman Tarik Glenn during a November 5th, 2006, game. Seymour was reportedly angered that Glenn was diving for Seymour's knees. Regardless, Seymour professed his regret for the incident and stated he would apologize to Glenn at their next meeting.