David Siang Hai Teoh is an Australian businessman. He is the executive chairman of TPG, a company he founded with his Taiwanese wife Vicky in 1992 after emigrating from Malaysia in 1986.

Reclusive, Teoh has only been photographed in public twice. A photographer staked out his house for three days in 2015, and in 2019 the proposed merger with Vodafone obliged him to attend court.

According to Forbes magazine, in 2016 Teoh was the 25th-richest person in Australia, estimated to be worth approximately US$2.9 billion. In 2020, the Financial Review Rich List assessed Teoh and his wife’s net worth at A$2.54 billion.

His four sons, Shane, Jack, John and Bob, have launched more than a dozen startup companies dealing in clothing, furniture, technology, and eyeglasses. In 2016 it was reported that his wife, Vicky, had substantial investments, including Vita Life Sciences Ltd, a pharmaceutical and healthcare company.

In August 2018, Teoh announced TPG was in discussions with Vodafone Hutchinson Australia about a proposed $13 billion merger. Teoh’s only comment about the proposed merger was the pricing would be “very aggressive” and that it would bring value to the customer. It was blocked by the Australian Competition and Consumer Commission on the grounds that it would lessen consumer choice in both the internet and mobile phone markets. But in early 2020 Vodafone and TPG were granted permission by the Federal Court to merge, paving the way for the stalled $15 billion deal to finally proceed.