Train operator Govia Thameslink Railway (GTR) has been fined £1m after a railway enthusiast was killed when he put his head out of a carriage window.
Simon Brown, 24, from East Grinstead, West Sussex, suffered catastrophic injuries when his head hit a signal gantry as he leaned out of a Gatwick Express train travelling at 61mph towards Wandsworth Common station in south London.
GTR, which runs the service, pleaded guilty to a health and safety breach at a previous hearing over Mr Brown's death in 2016.
Sentencing the company at Southwark Crown Court, Judge Jeffrey Pegden QC ordered the firm to pay a £1m fine.
It was also ordered to pay £52,267 in costs.
Mr Brown had been travelling on a Victoria-bound service on the evening on Sunday 7 August when he suffered head injuries after leaning out of the train.
An air ambulance crew was dispatched but he was pronounced dead at the scene.
Initial reports suggested the man had been decapitated, however British Transport Police later confirmed that was not the case.
Lucie Walker, a 21-year-old student who was at the station, told the Evening Standard: "I got off the train from Victoria and at once saw the ambulance helicopter that had landed nearby.
"There were lots of police around. The mood was very sombre."