T-Mobile US took a big hit this summer when it suffered a data breach that exposed personal data on at least 54 million people. The operator’s bonafide position as the market leader on 5G evaporated in the perception of many almost overnight.

No wonder T-Mobile CEO Mike Sievert was immediately thrown a hardball question about the incident at the Goldman Sachs Communacopia event. “That’s a great place to start,” he said, undoubtedly hoping he could talk about anything else. 

“We just take this very, very seriously. No company like ours is immune to these kinds of criminal attacks against us and our customers, but at the same time it’s our obligation to keep our customers’ data protected, and we need to do better,” Sievert said.

“Getting after the root causes is critically important because these kinds of things cannot be allowed to happen. And for us, what we felt we needed to do was really undertake a long-term strategic investment in this area,” he said. “I'm not going to be satisfied until we are second to none globally when it comes to cybersecurity and we knew we needed help.”

That help came in the form of long-term contracts T-Mobile signed with Mandiant and KPMG shortly after the operator confirmed the initial scope of the attack. “We're going to make sure that we learn from this,” Sievert said.

“As it relates to the business, you know, look, there was an impact,” he said without disclosing the extent of the impact. 

“This is unfortunate, I think customers realize that these attacks are an ongoing series of events from companies in every industry, and that their data is already out there,” Sievert added. “They of course are concerned, but on the other hand, the evidence appears that most customers — I think, unfortunately, because of how common these attacks are — are willing to look forward.”

One point of impact that could be particularly troublesome for T-Mobile’s growth prospects rests with the enterprise market. The operator’s business services unit has a current market share below 10%, and it intends to increase that up to 20% by 2026.

Enterprises of all types and sizes care deeply about security. And now, instead of highlighting multiple meaningful leads on 5G in the U.S. and globally to prospective business customers, T-Mobile has to overcome issues of trust. 

This all begs the question: If T-Mobile recently, and for the fifth time in three years, failed to protect private information, why would an IT decision maker take the risk?

Sievert’s comments today about the commonality of these attacks and customer data already being leaked elsewhere, while oftentimes true, won’t be convincing enough for most enterprises. None of that changes the fact that T-Mobile is in the undistinguished position of having suffered the largest carrier breach on record, according to analysts. 

Other than that, the operator has a good story to tell on 5G network performance and coverage. 

“Unlike consumers that go on reputation, enterprises study it, they check out 100 phones from us and our competitors and they take a hard look, and we’re winning because they look at the reality of what happens,” Sievert said.

“They know we’re ahead for the next few years and they’re picking us,” he insisted. 

“Remember, we have today still the nation’s only standalone 5G network. That means that it’s 5G from the handsets to the radios and all the way into the core, and that means we can begin working with partners on advanced 5G services,” Sievert added. 

“We’re in active trials today with 12 of the Fortune 50 in potential 5G services. This is something that we can do outside of a lab because we’re already deployed nationwide” on low-band spectrum and reach more than half of the U.S. population with mid-band 5G, he said.

T-Mobile plans to expand its mid-band 5G footprint to cover 300 million people by the end of 2023.