The Information Commissioner’s Office (ICO) raided a call centre in Hove on Thusrday thought by to be responsible for millions of nuisance calls.
Using automated technology, the company is thought to be making four to six million anonymous calls a day on debt management and payment protection, without consent from the victims who cannot opt out of the scheme.
Another premises in Maidenhead thought to host the company’s servers was also raided.
David Clancy, enforcement team manager at the ICO, said: "It is astounding to think this one small company has the ability to pester millions of people with unwanted calls on a huge scale.
"Thanks to this raid we have seized information that will enable us to discover where this organisation is sourcing their data and prevent them from selling it to third parties."
Following the raid the ICO will decide whether to penalise the company, which could be on the receiving end of a fine of up to £500,000 or an enforcement notice if it is found to have been breaching data rules.
"The rules on making recorded messages are clear, and if the evidence proves the law has been broken we will act," Clancy said.
The case comes just a few weeks ahead of government plans that will lower the burden of proof on the ICO in nuisance call campaigns.
From April 6 the office will only have to prove that there has been a serious breach of the law to take action in such instances, having previously been required to demonstrate "substantial damage or substantial distress" had been inflicted before it could act.
However the law is not retrospective, and so the Hove case will be investigated under previous guidelines.
