Ho Pin, publisher of Chinese-language Mingjing Monthly, said the magazine got the document through other channels and that its contents were widely available before it published its article in August, the Hong Kong-based South China Morning Post reported.
State-run Xinhua news agency which reported the arrest of Gao, a Beijing resident aged 70, yesterday did not give details of the Communist Party document she alleged to have leaked last June.
The timing suggests it coincided with reports of a confidential party circular known as Document No. 9 last year that ordered government officials to tackle seven subversive influences on society, including Western constitutional democracy and "universal values" such as human rights and free speech, the Post reported.
The Mingjing Monthly published the document in August claiming it as an exclusive on its cover. It was also published on Mingjing's website.
State television aired footage of Gao in prisoner's uniform making a confession to the police.
"As far as I know, we had obtained the major contents long ago," said Ho.
Ho said the arrest of Gao was a move by the Communist Party to crack down on dissidents ahead of the June 4 anniversary of the Tianannmen Square pro-democracy protests in 1989.
Gao was among a number of civil rights activists who have been placed in criminal detention ahead of the anniversary.
"The document did not involve information that poses national security risks, nor would it have any impact on the market," Ho said.
"It was only a policy guide within the Communist Party, which had already been reported in many media outlets including the People's Daily," he said.
Police detained Gao on April 24 and seized substantial evidence at her residence.
Gao was suspected of illegally obtaining a highly confidential document and sending an electronic copy of it to an overseas website in June last year, a police statement here said.
The document was later published at the website and widely reposted abroad, state-run Xinhua news agency reported.