Earlier, a lower court ruled in Feb this year that Assange should be sent to face questioning by Swedish authorities over claims of sexual assault against two women. Meanwhile, Assange denies the allegations and claims they are politically motivated.
Some experts argued that, WikiLeaks may not have the strength to survive if Britain's high court judge decides on Wednesday (today) in favour of a Swedish request to extradite Assange to face trial over rape allegations.
Tim Maurer, who has studied the group and its membership, said he wasn't sure whether its remaining staff had the tech savvy to run the site if its founder is absent. "I don't think that WikiLeaks will exist without Assange," said Maurer, a research associate at the Harvard University's Belfer Center for Science and International Affairs.
Depending on the Wednesday (today) verdict, either Assange or the Swedish authorities can theoretically take the case a step further to the Supreme Court in London, the highest legal authority in the land.
For much of the past year Assange has been running the website from a supporter's country manor in eastern England, where the terms of his bail have put him on virtual house arrest. The 40-year-old Australian says he has 20 staff members, but it's unclear who might take over were he jailed.
The former hacker caught the world's attention when WikiLeaks released tens of thousands of classified diplomatic files allegedly obtained by a US serviceman who is now in prison in the United States.