Scottish Labour leadership candidate Anas Sarwar has announced that he has relinquished all his shares in his family’s wholesale business.
The move follows criticism that United Wholesale (Scotland) did not pay all staff the real living wage.
Mr Sarwar said he had taken the step to “demonstrate his commitment to public service”.
He added that it was also to ensure “the campaign debate can fully focus on policy issues”.
The Glasgow MSP is standing against Richard Leonard in the Labour leadership contest, which was sparked by Kezia Dugdale’s resignation last month.
Earlier this week Mr Sarwar denied being “one of the few” as he defended his family’s firm over its failure to pay the real living wage to all staff.
He said United Wholesale (Scotland) Ltd did not pay everyone the real living wage of £8.45 an hour because it was “voluntary”.
Mr Sarwar’s minority shareholding in the firm is said to be worth £4.8m.
In a statement released on Saturday, Mr Sarwar said he had signed a discretionary trust deed that meant he could never access the assets.
The beneficiaries of the trust will be Mr Sarwar’s three young children, who he said would not access the assets until they were adults.
The statement read: “To demonstrate his commitment to public service and to ensure the campaign debate can fully focus on policy issues, Mr Sarwar has today taken the decision to relinquish all his shares in United Wholesale (Scotland).
“The Glasgow MSP has always been fully transparent about his shareholding in the highly successful employer set up from scratch by his father, which Mr Sarwar plays no active role in and voluntarily waived his right to any dividend after becoming an MSP.
“He will now be unable to access the assets or take any remuneration for his lifetime, demonstrating his unswerving commitment to public service.”
Mr Sarwar said: “I will never apologise for being my father’s son. I am incredibly proud of his achievements, building a company from scratch than now employs around 250 workers – many in Nicola Sturgeon’s own constituency.
“Scotland has cradled my family, nurtured it and gave it opportunity and success.
“And it’s the Labour Party that allowed them to share that success to help others.
“I’m in the Labour Party because of those values and because I know our party remains the single best vehicle for change in this country.
“That’s why I have dedicated my life to fighting for the values I believe in.”
Mr Sarwar said earlier this week he was not a director of United Wholesale, had “no say” in how it operated and did not receive any remuneration from it.
He also said the firm did not pay everyone the real living wage because it was voluntary while he wanted to make it mandatory.
And he told BBC Scotland on Wednesday that he had received assurances from the company that it “wants to transition to a real living wage for all employees”.