Banking giant HSBC is among the companies to have stopped using Bell Pottinger since the scandal emerged.
Bell Pottinger was being paid £100,000 a month by Oakbay.
In a busy day of news for the firm, after chief executive James Henderson quit in light of the PRCA sanctions on Monday, the man who many had tapped to take his spot, John Sunnucks, the head of Bell Pottinger's financial PR division tendered his immediately effective resignation on Tuesday evening.
In response to the decision, Bell Pottinger said it "accepts that there are lessons to be learned but disputes the basis on which the ruling was made" and said that it would "refocus on delivering outstanding work for our clients and looking after our people".
Bell Pottinger left the Oakbay account in April, and in July the group said that it had fired one partner and suspended another, as well as two other employees, as a result of the campaign.
The billionaire Guptas have been accused of benefiting financially from their close links to Jacob Zuma, the South African President.
At least four major clients, including Investec, are also understood to have ditched Bell Pottinger's services over the racism row.
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Switzerland will travel to Portugal in the final round of matches knowing a draw will likely be enough to win the group. Meunier then completed his hat-trick seven minutes later, as the PSG defender turned home Kevin De Bruyne's cross.
What makes this outcome more rewarding is that this woeful outcome for Bell Pottinger has been wrought without the need for society to introduce expensive litigation action for the transgressor to suffer the consequences of its unwarranted conduct.
Waitrose, which prides itself on its ethical stance, would not say whether it will definitely continue to employ the embattled agency.
Since then, a number of clients - including worldwide bank HSBC, South African investment bank Investec, mining company Acacia and construction company Carillion - have walked away.
"Due to reasons of confidentiality we do not comment on business matters of this nature", a BDO spokesperson said.
Chime, co-owned by U.S. investment firm Providence Equity Partners and Sir Martin Sorrell's WPP group, gave up trying to sell its 27 per cent holding and is understood to have given the stake to the company's board several weeks ago as the scandal reached boiling point.
Earlier this week, co-founder Timothy Bell, who left the firm a year ago, told BBC's Newsnight programme that he thought the agency is unlikely to survive.