A court on Monday ruled that a group led by a former key member of the AUM Shinrikyo cult does not require state surveillance, finding that it has separated from the founder of AUM who is on death row for masterminding the 1995 sarin gas attack in Tokyo and other crimes.

The Tokyo District Court rescinded state surveillance measures taken against the group called Hikarinowa, or the Circle of Rainbow Light, established in 2007 by Fumihiro Joyu, 54, as he left the AUM Shinrikyo group, which has renamed itself Aleph. The lawsuit was filed by Hikarinowa.

In handing down the ruling, Presiding Judge Toshiyuki Hayashi said Hikarinowa is "significantly different in nature" from Aleph, which is deepening a sense of reverence toward AUM founder Shoko Asahara, whose real name is Chizuo Matsumoto.

The judge cited Hikarinowa's "basic principles," adopted at the time of the group's launch, which deny unquestioned faith in Matsumoto.

He also said the court could not determine whether senior members of Hikarinowa and Aleph were communicating when the government's Public Security Examination Commission decided in 2015 to renew a three-year surveillance program for the two successor groups to the AUM Shinrikyo cult.

"We cannot see them as one group," the judge said.

The surveillance measures were implemented in line with a law to control organizations that have committed acts of mass murder. The law enables authorities to raid buildings managed by the organizations and obliges them to report their assets. The commission decides on the renewal of steps every three years.

The commission has said that Hikarinowa "ostensibly denies ties" with Aleph but "in reality preaches following" Matsumoto.

Hikarinowa, meanwhile, has insisted that it is publicizing the danger of the teachings of the AUM Shinrikyo cult. After the ruling was handed down, Joyu hailed the court's decision, saying it recognized that the arguments made by public security authorities were "groundless."

Aleph has also sought to be no longer subject to state surveillance, but the judge dismissed the claim.

According to the Public Security Intelligence Agency, there are about 1,500 Aleph believers and about 150 Hikarinowa followers.

Hikarinowa is said to own eight facilities nationwide, including what it calls a "headquarters teaching room" in Tokyo's Setagaya Ward, according to the agency.