The head of Save the Children Australia says the charity has been treated as a scapegoat by the Australian and Nauru governments during its time at the asylum seeker detention centre.
The charity wound up its operations on Nauru on Saturday, after the Australian government granted the welfare contract to the multinational, Transfield Services.
Its tenure has been controversial, with Canberra last year deporting nine workers after they were accused of encouraging detainees to self harm and fabricate stories of abuse.
An independent inquiry later found no evidence of this.
The charity has since been subject to police raids on Nauru.
Save the Children's chief executive, Paul Ronalds, says they have been unfairly targetted.
"I suppose when the other main provider of services for the Australian government is a large multinational it is easier to target an organisation like the Save the Children, or at least it might appear that way to the governments of Australia and Nauru. But as the Moss Report found, Save the Children staff have worked with the utmost professionalism at all times."
Paul Ronalds says Save the Children is seeking compensation for the wrongful deportation of staff.