Why did Tuas (ASX:TUA) shares crash over 60% on May 18?

Tuas shares plummeted after Singapore's telecom regulator, the Infocomm Media Development Authority (IMDA), launched an investigation into its subsidiary, Simba Telecom.

What exactly is Tuas (ASX:TUA) accused of doing in Singapore?

Tuas' wholly owned Singaporean subsidiary, Simba Telecom, is accused of utilising radio frequency spectrum bands without proper authorization. If the IMDA proves these allegations, the unauthorised usage represents a severe breach of Singapore’s Telecommunications Act and violates Simba's facilities-based operations licence.

How is Tuas management responding to the Singapore investigation?

Tuas confirmed that Simba Telecom is cooperating fully with the IMDA probe while the Tuas board urgently reviews the spectrum allegations. Management has promised to keep the market updated as ongoing discussions with transaction counterparties continue, though their immediate leverage appears limited by the looming contractual deadline.

What is Keppel’s "Plan B" and how does it affect Tuas (ASX:TUA)?

Keppel, the parent company of M1, has already announced a backup plan to retain and rightsize the telecom asset instead of selling it to Tuas. This signal from the vendor suggests they are preparing to walk away from the transaction, materially lowering the probability that Tuas will successfully complete the M1 acquisition.

How risky is Tuas (ASX:TUA) stock after this regulatory news?

The stock now carries heavily elevated regulatory and strategic risk, shifting its profile from a growth narrative to a highly speculative turnaround play. Investors face the dual uncertainty of a collapsed multi-billion dollar expansion strategy and potential severe regulatory penalties or licence conditions imposed on Tuas' core subsidiary, Simba Telecom.

Image for illustrative purposes only. Not a real photo.

Tuas shares crash 60% amid Singapore probe

Q: What does the regulatory freeze mean for the Tuas acquisition of M1?

The regulatory intervention places the high-stakes S$1.43 billion merger on thin ice because the deal has a strict long-stop deadline of May 21. With only days remaining and a complex regulatory investigation just beginning, there is virtually no runway left to resolve the compliance issues before the contractual agreement potentially expires.

Written by Heidi Cuthbert Published May 18, 2026, 2:15 AM

Shares in ASX-listed telecommunications provider Tuas (ASX:TUA) crashed over 60% on the morning of May 18 morning, plummeting to $2.44 per share.

The market sell-off followed shock revelations that Singaporean regulatory authorities have launched an investigation into the firm's wholly owned local subsidiary, Simba Telecom.

The Infocomm Media Development Authority of Singapore announced it has suspended its regulatory review of Tuas' highly anticipated S$1.43 billion acquisition of M1.

According to the regulator, the suspension was triggered by evidence suggesting Simba utilised radio frequency bands it was not authorised to use.

If proven, the unauthorised spectrum usage constitutes a severe breach of Singapore’s Telecommunications Act and violates the explicit conditions of Simba's facilities-based operations licence.

The regulatory intervention places the high-stakes merger on thin ice. Tuas confirmed that Simba is cooperating fully with the IMDA probe and noted that its own board is urgently reviewing the circumstances surrounding the spectrum allegations.

The share purchase agreement for the M1 transaction has a looming long-stop deadline of May 21.

With only days remaining and a complex regulatory investigation underway, the tight runway leaves almost no time to resolve the compliance cloud before contractual deadlines expire.

In response to the freeze, M1’s parent company, Keppel, has already announced a "Plan B" to retain and rightsize the telco, whilst Tuas has promised to keep the market updated as ongoing discussions with counterparties continue.

At the time of reporting, Tuas’ share price was $2.04.