The 24-year-old France international posted a tweet suggesting he was unhappy to be told his future lay at St Mary's, and then followed that up with an official transfer request despite reports he has no release clause and three years left to run on his contract.
Schneiderlin has been linked with a move to join former Saints boss Mauricio Pochettino at Tottenham Hotspur, with Spurs thought to be ready to pay £20m for the midfielder.
Pochettino is reportedly keen for Schneiderlin and Southampton striker Jay Rodriguez to join him at White Hart Lane but executive director Les Reed and chairman Ralph Krueger are adamant that there will be no further departures from the club, prompting Schneiderlin to demand a move.
Schneiderlin said via his Twitter account in the wake of talks over his future: "6 years of an amazing journey #saintsfc DESTROYED in 1 hour !!!(sic)."