Tasmanian Liberal MP Adam Brooks has resigned as the head of the mining maintenance company he founded.
Mr Brooks has stood down as managing director of Maintenance Systems Solutions.
In May, the State Opposition called on the Greens to apologise over claims of a conflict of interest.
Greens MP Paul O'Halloran put forward a motion in Parliament suggesting Mr Brooks could use his position as Opposition mining spokesman to further his private interests.
The Opposition called it a 'cowardly slur' and said it would seek legal advice on comments made outside the House.
Mr Brooks will remain a shareholder in the business.
MSS spokesman Tim Swain says the company will no longer operate in Tasmania.
"Recent 'conflict of interest' accusations against the owner, while baseless, have the potential to be damaging to the company and to our clients, and we no longer accept being a target of politically-motivated attacks," he said.
Mr Swain said it was a difficult decision that would potentially cost jobs.
Grange Resources chief operating officer Wayne Bould has been appointed to replace Mr Brooks.