Phornthep Phornprapha & family was born in Bangkok, Thailand, Thailand. Phornthep Phornprapha & family is #1419 in List Billionaires People In The World. Phornthep Phornprapha runs privately held Siam Motors Group, producer of Nissan cars and trucks in Thailand. Other interests include auto parts, logistics, construction equipment and hotels. Siam Motors has funded an automotive engineering and development center at Thammasat University's campus in Pattaya. Phornthep has a board seat at Bangkok Bank, chaired by fellow lister Chatri Sophonpanich.