A judge has dismissed a claim by Arthur Scargill for the NUM to reimburse him nearly £6,000 for the cost of installing a new security system at his Barnsley home.
The union has been responsible for paying the costs of Mr Scargill's security since the 1970s when the police advised he needed protection.
However, he had the new alarm installed without the union's approval.
The judge said it was reasonable for the NUM to ask for other quotations for the work as it was a "significant sum of money" and dismissed Mr Scargill's claim for reimbursement.
She also dismissed a counter claim by the union for Mr Scargill to reimburse alarm maintenance costs they had paid to him.