Between January 2010 and March 2011, the Scottish government bought £10m-worth of de-icing salt from several sources, but none from Southampton-based Nationwide Gritting Services (NGS).
NGS said the orders should have gone out to tender and launched legal action. The Scottish government said that it had only not gone out to tender when there was an emergency situation.
Judge Lord Woolman has now found in favour of Scottish ministers. A Scottish government spokesperson welcomed the opinion "which found that the case against the Scottish government had no merit".
They added: “In the face of extremely severe winter weather the Scottish government acted properly to keep the economy going and to protect public safety. Securing additional salt supplies helped to keep the majority of our roads open and to keep people on the move in exceptional circumstances.
“Following the two severe winters Transport Scotland and its partners have made significant improvements to the winter service. Additional gritters, greater use of technology and getting information to people when they need it most are just a few of the ways winter treatments, decision making processes and communications have been strengthened.”
The full opinion can be read at http://www.scotcourts.gov.uk/search-judgments/judgment?id=ee9bafa6-8980-69d2-b500-ff0000d74aa7