Sir Kevin Barron, MP for Rother Valley, John Healey, MP for Wentworth and Dearne, and Sarah Champion, MP for Rotherham sued Collins, who represents Yorkshire and North Lincolnshire.
The High Court case was brought after Collins made comments in a speech at the Ukip party conference in September 2014.
In 2015, a judge said Collins’ words referred to what the MPs knew of the details of exploitation that took place in the South Yorkshire town, the North-West Evening Mail reported.
Collins argued that her words were meant as a political speech rather than expressions of fact.
The court had heard how Collins had tried to have the case delayed on numerous occasions.
In 2014, a report found about 1,400 children had been abused in and around Rotherham between 1997 and 2013.