The Falcons confirmed that Weatherspoon, a linebacker from Missouri, had agreed to a five-year contract, but they didn't release financial terms. However, a league source told NFL Network insider Jason La Canfora that Witherspoon received a five-year, $17.5 million deal with $10.5 million guaranteed.
Weatherspoon's agent, David Dunn, didn't immediately return a phone call to The Associated Press.
This is the third consecutive year under general manager Thomas Dimitroff that the Falcons have had all their draft picks signed before the start of training camp. This year's camp begins Friday.
Weatherspoon was the No. 19 overall pick in the NFL draft. He's expected to compete for a starting job at outside linebacker.
The Associated Press contributed to this report.