Coughman (6-4, 313) originally entered the league as a free agent from the Canadian Football League, signing with the Seattle Seahawks in 2012 and being waived after spending time on the Seahawks practice squad. He signed with the Dallas Cowboys during the 2013 offseason and was waived at the end of the preseason. Coughman signed on to the Buffalo Bills’ practice squad and spent the 2013 season there. After being waived by the Bills during the 2014 preseason, Tampa Bay claimed him off of waivers, but waived him prior to the start of the 2014 regular season. Most recently, Coughman spent time on the Washington Redskins practice squad.
Dye (6-0, 190) played collegiately at Heidelberg University (2011-14). In his four-year career, the Fairfield, Ohio native caught 116 passes for 2,298 yards and 26 touchdowns. As a senior, Dye caught 57 passes for 1,022 yards and 14 touchdowns.
Humphries (5-11, 195) is a native of Spartanburg, South Carolina and played collegiately at Clemson. In 53 games played with the tigers, Humphries recorded 127 catches for 1,097 yards and three touchdowns, while also returning 69 punts for 476 yards and one touchdown. He ranks fourth in school history in games played and 10th in punt return yards.
Koster (6-1, 210) played collegiately at New Mexico Highlands, appearing in 31 games, totaling 338 tackles 39.5 tackles for loss, 12 passes defensed, 10.0 sacks, six fumble recoveries (one returned for a touchdown), five forced fumbles and three interceptions returned 51 yards with one touchdown. Koster set the NCAA Division II record for solo tackles in 2014, with 104, while earning Rocky Mountain Athletic First Team honors, second-team All-America honors by Daktronics and was a finalist for the Cliff Harris Award (given annually to the best non-Division I defensive player).
The team has also waived safety Shelton Johnson, wide receiver Chandler Jones, offensive lineman Matt Patchan, wide receiver Solomon Patton, wide receiver Josh Reese and linebacker Michael Reynolds.
Patton played in seven games with Tampa Bay last season, retuning 10 punts for 112 yards and 18 kickoffs for 416 yards.