Derby had pursued highly-rated playmaker Stephens during the summer transfer window as they looked to bolster their midfield following a spate of injuries to key players, but saw two bids rejected by Brighton - as revealed by HITC Sport.
Brighton were determined not to lose Stephens, with the player having established himself as a key member of their side since arriving from Charlton Athletic in January 2014.
The 25-year-old has played a key part in Brighton's flying start to the current campaign, with the Seagulls riding high at the top of the Championship table with six wins from their opening seven games.
Stephens scored his first goal of the season in the midweek victory over Rotherham United, and Hughton has been hugely impressed by the midfielder's contribution.
"We know the quality that he’s got," Hughton told the Brighton Argus. "He had a difficult time last season, missing the first half of it through injury, and probably spent the period when he got fit getting back into the rhythm of his game.
“He had a good pre-season and he’s giving us a really good contribution.”
Brighton will be looking for Stephens to maintain his fine form if they are to continue their flying start to the campaign and make a serious challenge for promotion to the Premier League this season.