The tourist bus, which was carrying around 50 people, rammed several cars after failing to brake on a bend near Avellino in southern Italy. It then smashed through the safety rail of a viaduct and plunged into the void, falling some 30 metres.
The prosecutors said chief Giovanni Castellucci and 11 other Autostrade (ASPI) employees should get ten years for failing to upkeep the rail.
The US-imported Jersey concrete barrier, corroded by salt used to keep the road ice-free in winter months, shattered on impact, leaving the bus to sail over the edge in one of Europe's worst road accidents.
Autostrade, which runs almost half of Italy's motorway network, has come under huge pressure since a bridge it maintained in Genoa collapsed in August, killing 43 people. Castellucci is under investigation for the collapse of the Morandi bridge, which had suffered from structural problems for decades, prompting severe criticism from engineering experts.
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Photo: Valery Hache/AFP