The lawsuit, filed on Thursday in Tokyo District Court, demands 1.4 million yen ($14,000) in damages for 63 medical professionals.

Google said in an emailed statement Friday that it was working "24 hours a day" to reduce misleading or false information on its platform, combining human and technological resources "to delete fraudulent reviews".

The lawsuit claims groundless negative reviews have been posted on Google Maps, a very popular app in Japan, which allows people to write in ratings of various institutions and their personal reviews.

Some comments are irresponsible and appear to be written out of spite and the "word of mouth" remarks take on a life of their own and are nearly impossible to refute, according to the lawsuit.

It said Google has done very little to fix the problem, despite complaints.

"The damage suffered is substantial, and the people have been powerless to fight back. We don't agree that the platform shares no responsibility," Yuichi Nakazawa, who leads the legal team for the plaintiffs, told reporters.

Some Japanese say they rely on what people say online about hospitals, including how long the wait was or what kind of care they received, rather than official sites.

But those online comments might be inaccurate and even detrimental to health care, those behind the lawsuit say.

Japan boasts a relatively widespread and affordable healthcare system, making the medical sector a hot topic in one of the fastest ageing societies in the world.

Class actions are relatively rare in Japan, though Google has been sued in the US and various other nations, accused of misleading advertising, violations of privacy and other problems.

The lawsuit in Japan is intended to highlight the potential dangers from Google's technology, the lawyers for the medical professionals say.

The damages they are seeking are symbolic, about 23,0000 yen per plaintiff.

Australian Associated Press