Upgrade to get full access to all premium news on Yahoo Finance and get more great articles like this free preview. The family office, which handles the investments of the ultra-rich, has become one of the fastest generators of wealth in the world from the US to Hong Kong and Singapore. An institution that dates back more than 150 years — when American financier John Pierpont Morgan first came up with the term to describe the personal investment arm for his growing art collection — has become a cornerstone of the financial system. The sector has expanded from a small…