The company’s petition for leave to appeal was denied this week, meaning the lawsuit can proceed to trial.

Web measurement firm comScore was sued by two individuals, Mike Harris and Jeff Dunstan, in 2011. Harris and Dunstan allege that the company exceeded the scope of a consumer’s consent to monitoring by intercepting phone numbers, social security numbers, usernames, passwords and credit card numbers, among other personal information.

ComScore has said that the claims in the lawsuit are “without merit”. However in April, Federal Judge James Holderman certified a class of “all individuals who have had, at any time since 2005, downloaded and installed comScore’s tracking software onto their computers via one of comScore’s third party bundling partners”.

Holderman also certified an additional subclass of “all class members not presented with a functional hyperlink to an end-user licence agreement before installing comScore’s software onto their computers”. Estimates put the size of the class at up to a million people.

ComScore sought to overturn this ruling and won support in the form of an amicus brief from the Direct Marketing Association, American Association of Advertising Agencies and Association of National Advertisers – among others – who warned that “an improper certification order has the probable impact of not only harming defendant comScore by chilling voluntary participation in its market research, but also adversely impacting many of the amici’s members who rely on web rating services of the defendant and companies like it”.