Toronto's real estate agency is launching a full-court attack against a plan to make more information available online, including the names and addresses of home sellers.

The Toronto Real Estate Board (TREB) claims the changes will invade the privacy of home sellers and buyers and may result in more fraud against its clients.

The country's largest real estate board says Canada's Competition Bureau wants it to release sensitive information about online real estate sales by removing safeguards used by its agents.

The Competition Bureau is demanding TREB release more information about its listings online, in a bid to even the competitive balance for online real estate websites.

In 2010, federal Competition Commissioner Melanie Aitken successfully fought to give private home sellers access to the Multiple Listing Service (MLS), which is the primary service through which homes are bought and sold in Canada.

The real estate industry has grown its online presence in recent years. The industry's main site, Realtor.ca, allows clients to browse homes over the Internet. Some information is restricted on the site and a real estate agent must grant access.

As the system stands now, TREB puts the onus on agents to keep personal and restricted information from the general public, though they can share it with clients. Much of it is also available via land record searches and other means.

The Competition Bureau now argues that TREB's information wall is unfair for independent online real estate sale sites and should be made publicly available. The case is expected to go before a competition tribunal in the fall.

If the change is implemented, the name and address of real estate sellers will be made available online, as will property floor plans and other information about homes for sale.

Negotiated sale prices and details of buyer mortgages would also be made publicly available, TREB said on Wednesday.

TREB claims making this personal information publicly available could be used to defraud customers in the Toronto area.

Von Palmer, chief privacy officer for TREB, warned consumers that "if you don't think criminals are looking for a one-stop shop, they are."

"How would you feel if you enlist a licensed realtor right now, you have your house on MLS and you go on the website and you can now see your name, coupled with your address, what your property sold for, you personal mortgage information, floor plans of your property, openly accessible to all?" Palmer said Wednesday in an interview with CTV News Channel.

"That invites a whole host of issues such as fraud, mortgage fraud is an issue, and someone's personal safety."

The other issue of concern, Palmer said, is that in their contracts with their agents, clients have not given permission for any of this information to be made publicly available.

TREB claims the vast majority -- 75 per cent of Ontarians, according to a poll -- are opposed to having the details of their housing purchase made public.

An Angus Reid Vision Critical poll released by TREB on Wednesday also finds that 70 per cent of Ontario homeowners do not want their personal contact information released.

"The results of this poll are overwhelming," TREB President Richard Silver said in a statement. "TREB strongly believes that REALTORS have an obligation to protect consumers' personal information."

The board has launched an online campaign against the Competition Bureau, including the website protectyourprivacy.ca, which features the image of a man peering through a window shade.