Charges have been dropped against three companies accused of failing to protect employees exposed during a Legionnaires outbreak in 2012.
The legal case against the North British Distillery Company Limited, Pera Services Limited and Chemtech Consultancy Limited ended on Friday when not guilty pleas were accepted.
Four people died after an outbreak of the disease in 2012. The source of the disease was never identified.
The case against two firms continues.
Ashland Industries UK Limited, and MacFarlan Smith Limited are both accused of health and safety breaches. They maintained their pleas of not guilty.
A hearing will go ahead on 30 July.
The five companies were originally charged under the Health and Safety at Work Act after allegedly exposing people to the legionnaires bacteria.
The charges were related to the maintenance and cleaning of cooling towers and are unconnected to the deaths of four people in the city during the outbreak.