CBRE, which lists this property on its website, says that One Causeway Bay has around 500,000 sq ft of office space across 24 floors and 55,000 sq ft of retail space in the 4-level retail podium.
Mandarin Oriental International, part of the Jardine conglomerate, confirms it is in talks to sell units at One Causeway Bay to Alibaba Group Holding.
According to the Hong Kong Economic Times, the deal involving 13 office floors in the property is worth some HK$7 billion.

