The line up of banks is still not finalised and ADNOC may add more advisors to the deal, said two of the sources, who declined to be named as the matter is not public.
ADNOC, HSBC, OCI and Citigroup declined to comment. First Abu Dhabi did not immediately respond to a request for comment.
While HSBC will allow the holding, sale and outgoing transfer of MicroStrategy shares, it will forbid new purchases or incoming transfers, said the message dated March 29.
The pan-European STOXX 600 rose 0.2pc, reversing declines from earlier in the session, with automobile stocks rising for a fifth day in the past six sessions.
The planned disposal is part of HSBC Chief Executive Noel Quinn's strategy to slash costs across the banking group and Reuters previously reported that Cerberus was among two remaining bidders.
Any sale could involve a token price, with HSBC having to plough in some 500 million euros ($595 million) to finance the necessary restructuring, Reuters previously reported.
Beijing and Hong Kong authorities are also drawing up broad plans to ensure all politicians and public officials are "staunch patriots", including within the judiciary.
Meng's arrest caused tensions between Beijing and Ottawa, and soon afterward, China detained two Canadians, who continue to have limited access to legal counsel or diplomatic officials.