Greyhound Recycling and Recovery has dismissed reports that that it is to be investigated by the Office of the Data Protection Commission.
Dublin City Council handed over information on 140,000 customers last week to Greyhound in a deal which allows the company take over the collection of the Council's waste in Dublin.
However, members of the public have complained to the Data Protection Commission about whether Dublin City Council complied with strict guidelines on data transfer.
Deputy Data Protection Officer Gary Davis said the investigation would follow two lines of inquiry.
"The first is to confirm that the sale of the waste-collection business complied with data protection requirements," he said.
"The second strand of the investigation is that Dublin City Council have apparently taken a decision to engage Greyhound separately to collect the debts of those people deemed to have outstanding waste charges. At first sight, that gives a cause for some concern to our office."
In a statement, Greyhound said: "The company has received no correspondence from the Office of the Data Protection Commission notifying it of any investigation.
"Greyhound Recycling and Recovery will co-operate fully with any investigation conducted by the Office of the Data Protection Commission where it is formally notified of any request to do so."
Greyhound also said the company’s customer database is separate to the database of customers owing unpaid debts to Dublin City Council.
"The two databases will not be matched and the matter of collecting unpaid debt from customers on behalf of Dublin City Council will be treated separately," the company said.
"Any customer who signs up to Greyhound Recycling and Recovery’s collection service will have their bin collected, even if they are listed on the database relating to customers who owe unpaid debts to Dublin City Council."