The 5-foot-11, 180-pounder graduated from Kansas in May and will be eligible to play for OSU this fall. He had 58 tackles, three interceptions, four tackles for loss and eight pass breakups for the Jayhawks in 2012.
Patmon originally announced his plans to leave KU last December via Twitter, noting that the decision was made "not by choice."
The three-year starter wound up playing in 35 career games for Kansas, tallying 142 tackles, 11.5 tackles for loss, 22 pass breakups and six interceptions. His transfer should immediately bolster a Cowboys secondary that finished 113th nationally in passing yards allowed last season.
In addition to Patmon, OSU also announced that it added offensive lineman Colby Hegwood to its roster. Hegwood comes to Stillwater from Pearl River (Miss.) Community College. He'll have three years of eligibility with the Cowboys.