Four accounting companies, including Deloitte and Grant Thornton, have already ruled out working with Boohoo, the Telegraph reported on Tuesday.
The review found that some workers had not always been properly compensated for their work and that many were not fully aware of their rights.
Shares dropped as much as 17 percent in afternoon trading in London after the Guardian cited auditors’ findings that more than a dozen UK suppliers may be paying substandard wages.
The deal could be priced by mid-September and is likely to raise around £1 billion through the sale of new and existing shares, according to sources familiar with the matter.