Although the memo has already been posted on the Financial Times' Alphaville website and has been widely reported in the press, Northern Rock has moved to block the document outlining sales options and showing that Northern Rock potentially owes Â£6 billion to the Bank of England by 2010.
In the firm's defense, Northern Rock says further publication of the document could jeopardise moves to save the bank.
The High Court has agreed to ban any more publication of the memo, but has disallowed any further restrictions to be legally binding.
"The company believes that further speculative reporting based on the illustrative information in the memorandum may jeopardise the complex discussions and negotiations taking place," a statement from Northern Rock read.
Meanwhile, Friday is the deadline of Friday for takeover bids for Northern Rock, which could involve sale of the whole company or sale of certain components.
Northern Rock has been very much affected by the sub-prime crash in the US and will have borrowed emergency funds from the Bank of England to the tune of Â£24 billion by the end of the year.