Teoh, who despite running one of Australias largest telcos has managed to maintain anonymity, runs gauntlet of media

Wed 11 Sep 201909.54 BSTLast modified on Wed 11 Sep 201922.22 BST

Billionaire David Teoh arrives at court in Sydney being photographed by the media for only the second time. Photograph: Asanka Ratnayake/Getty Images

Finally, the reclusive billionaire emerged. David Teoh, estimated to be worth $3bn, made his debut before the cameras on a fine spring day outside the federal court in Melbourne on Wednesday.

As he stepped into the witness stand shortly after 3pm, Teoh gave away the extraordinary level of anonymity hed been able to maintain even while running one of Australias biggest telecommunications companies, TPG.

But any hopes his evidence, given in a case where the company he founded and ran is challenging a decision by the competition regulator that stops it merging with rival Vodafone, might reveal the inner life of one of Australias most enigmatic business people were soon dashed.

Instead, under cross-examination by QC Michael Hodge himself a well-known character thanks to a stint as counsel assisting last years banking royal commission Teoh gave evidence littered with technical jargon about transmitters, antennae, cloud Ran and massive Mimo.

Before yesterday there was only one known photograph of Teoh, taken by a Fairfax photographer who staked out his home in Sydneys eastern suburbs for three days in 2015.

So his willingness to run a gauntlet of lenses and subject himself to hours of detailed questioning at the hands of one of Australias least gentle silks indicates how important to him the $15bn merger must be.

There is also a lot at stake for the Australian Competition and Consumer Commission.

It reckons that the merger would kill off any prospect that Australians might benefit from a fourth mobile network, to compete with the ones already run by Telstra, Optus and Vodafone.

In 2017, TPG splashed $1.2bn to buy a chunk of spectrum in the 700MHz band so that it could build the network a move the court has heard would have been disruptive to the entrenched players and challenge the dominance of Optus and Telstra.

It would have been a bold move into the mobile phone business for the company, which Teoh founded after emigrating from Malaysia in 1986 and built into one of Australias best-known internet providers.

But TPG says it abandoned the plan in January this year, about five months after the then communications minister, Mitch Fifield, effectively banned the participation of Chinese tech giant Huawei in the rollout of next-generation 5G mobile phone networks.

However, the ACCC has told the court that if the merger is stopped there is a good chance TPG will go ahead and build the network anyway rather than let its $1.2bn investment in spectrum go to waste.

TPG has argued the easy upgrade path from the older 4G technology to the new 5G one offered by Huaweis equipment was one of the key reasons it chose to go with the Chinese supplier.

With Huawei out of the picture, TPG now argues it has no prospect of getting a network up and running.

Much of Hodges questioning on Wednesday afternoon was devoted to trying to undermine this proposition.

But getting the answers he wanted from the quietly spoken Teoh was heavy going for Hodge.

While English might not be Teohs first language, he clearly had no difficulty with all the talk of BBUs, small cell formats and the like.

Under close questioning from Hodge, he was forced to admit that at the time TPG decided to go with Huawei one of the key bits of technology needed to upgrade the network to 5G did not exist.

He also faced detailed questions about whether the board of TPG required a financial model before agreeing to lash out on the 700MHz spectrum.

Hodge asked the same question six times: Whether you had modelled the outcomes or not was not a bar to you offering hundreds of millions of dollars to buy the 700MHz spectrum?

But he didnt really get an answer, even after the judge hearing the case, John Middleton, helped out by asking it again twice.

I dont want to say the wrong thing, Teoh told the court. I prefer your honour to bring up the documents to go through because I dont want to make a mistake.

Teoh will return to the stand when the hearing continues on Thursday.