Major developers such as Menolly Homes and Gannon Homes are increasingly opting to sign agreements with cable television operators that effectively tie residents to using one provider, leaving them unable to opt for an alternative service.

A Competition Authority spokesman confirmed last week that a number of complaints have been received about the "exclusive nature of the contracts" and that it is now engaged in a so-called "assessment phase" of the issue. This process could take either weeks or months to complete and may then proceed to a formal competition investigation. He declined to provide details for confidentiality reasons.

While the agreements may not always be exclusive on paper, they often effectively are in practice. Developers can retain control of new developments for years before formally handing them over to an independent management company. During that period the developer can block any third-party infrastructural work on a site, allowing a cable operator a lengthy period to generate a return on its investment.

Brian Keenan, managing director of Keenan Property Services, said that while developers can retain control of developments on paper for some time, legislation is being drafted that is likely to address such issues and possibly introduce timelines for the transfer of developments to management companies.

A spokesman for the National Consumer Agency last week said that there is clearly "a matter for consumer concern" over the practice of exclusive cable deals, and that it appears that consumers "are not being offered choice". He said that the agency will now examine the issue.

The boom in residential construction has allowed new entrants to the Irish market to build business on the back of partnerships with developers. Companies such as Magnet Networks and Broadworks Inc make deals to install infrastructure in developments. The payback comes from having a captive audience that may be unable to subscribe to a competing service.

Magnet Networks' marketing director Charlie Ardagh last week defended deals with developers.

"We don't believe we are breaching any competition law, but we will be cooperating fully with any investigation, " he said. "We have never paid for access to a site." He added that not all developments are exclusively serviced. In a major construction project in Adamstown in Dublin, Magnet Networks is one of two operators licensed on-site. The other is NTL while Eircom is also providing telephony services to new residents.

Ardagh said that incumbent cable providers simply hadn't been able to keep up with the rapid growth in housing construction and that it made sense for developers to have services in place before people moved into new homes.

A UPC spokeswoman said that it does not enter into exclusive agreements with developers, but does work with developers to service new developments. Broadworks- acquired last year by businessman Pat Alley - declined to comment.