Shintaro Tamatsukuri joined J.P. Morgan on Friday as the executive director of energy trading based in Singapore.

Tamatsukuri was the head of energy trading with Goldman Sachs in Tokyo, where he had worked since 2005. Prior to Goldman Sachs, Tamatsukuri worked with Japanese trading house Mitsui & Co (8031.T) for more than ten years.

"Regulations regarding banks' proprietary trading are becoming increasingly tighter so J.P. Morgan wants to expand the customer flow business, which is basically going back to basics of the banking sector," said the source, who declined to be named.

Tamatsukuri could not be reached. A spokeswoman with J.P. Morgan in Tokyo declined to comment.

Flow business is the business a bank does trading in markets on behalf of customers, while proprietary trading is that which a bank does for its own profit.

Regulation have become tighter on proprietary trading since the financial crisis in 2008, hitting banks' profit levels.

(This story has been corrected to say J.P. Morgan spokeswoman, not spokesman, in the fifth paragraph)

(Reporting by Ikuko Kurahone in London; Additional reporting by Osamu Tsukimori in Tokyo; Editing by Alison Birrane)

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