Dr Tan started his investment career at SEACORP, Malaysia (now known as Amanah Capital Partners Bhd). Dr Tan was with SEACORP, which owned 100% of the first unit trust company in Malaysia & Singapore for 4 years and 7 months from 1976 – 1981
Pheim Asset Management Sdn. Bhd. ( Pheim Malaysia ), one of the maiden asset management company in Malaysia when the asset management industry in Malaysia was first liberalised was founded by Dr Tan Chong Koay and began its operation on 4th January 1994.