When Nikesh Arora was named CEO of Palo Alto Networks in June 2018, the cybersecurity company was valued at about $19 billion and was taking on large networking vendors like Cisco and Juniper, which were building security into their products.

Seven years later, Palo Alto’s market cap has expanded by sixfold, driven in part by an acquisition spree that’s seen Arora spearhead more than 20 deals in an effort to create a one-stop shop for all things cybersecurity.

Arora’s ambitions took a dramatic turn last week, when Palo Alto announced by far its biggest bet to date: the $25 billion purchase of Israeli identity security platform CyberArk.

Wall Street’s reaction so far has been downbeat, with multiple analysts downgrading the stock, and the shares dropping 16% since news of the deal first leaked out last Tuesday.

Not only does CyberArk represent Palo Alto’s heftiest deal in the 20 years since its founding, but it’s the second-biggest U.S. tech acquisition announced in 2025, after Alphabet’s $32 billion purchase of Wiz, another cloud security company from Israel.

Alphabet had become a more notable player in Palo Alto’s universe even before the calendar turned. In the company’s 2024 annual report published in October, Palo Alto named Alphabet as a competitor for the first time, listing it alongside Cisco and Microsoft as companies “that have acquired, or may acquire, security vendors and have the technical and financial resources to bring competitive solutions to the market.” In 2023, Cisco paid $28 billion for Splunk, which focuses on data protection.

The era of cybersecurity megadeals coincides with a surge in the number of sophisticated cybercrimes tied to rapid advancements in artificial intelligence.

With CyberArk, Palo Alto is making a big splash in the identity management market, taking on the likes of Okta as well as Microsoft and IBM’s HashiCorp. It also puts the company into further competition with CrowdStrike, the other pure-play security company that’s topped $100 billion in market cap.

In an interview with CNBC soon after last week’s announcement, Arora said CyberArk fits squarely into his company’s focus on AI and, in this case, the complexities that come with granting permissions and access. Arora said that with M&A he looks for emerging trends, particularly when it involves technology that’s at a crossroads.

“Our entire acquisition strategy, our organic product growth strategy, our selling strategy, has always been based on that approach,” said Arora, 57, who’s seen his personal wealth top $1 billion with the big run-up in the stock.

In CyberArk’s earnings report last week, the company said revenue jumped 46% in the latest quarter to $328 million, equal to about 14% of Palo Alto revenue, based on the most recent report. Arora said in the conference call announcing the deal that he intends to work with CyberArk CEO Matt Cohen and Chairman Udi Mokady to “accelerate the pace of innovation.”

“We look for great products, a team that can execute in the product, and we let them run it,” Arora told CNBC. “This is going to be a different challenge, but we’ve done well 24 times, so I’m pretty confident that our team can handle this.”

Most of Arora’s acquisitions over the years have been of smaller startups. That includes a $400 million deal to buy Dig Security and the $625 million purchase of Talon Cyber Security in 2023. Last month, the company closed its takeover of Seattle-based startup Protect AI for an undisclosed amount.

Before joining Palo Alto, Arora spent a decade at Google, including his last three years there as chief business officer. Some analysts called him the “acting CEO,” due to his lengthy roster of responsibilities, such as strategic partnerships and navigating the needs of advertisers.

In 2014, Arora left Google to join SoftBank as head of its internet and media operations business and vice chairman of the overall company. At SoftBank, Arora had been tapped as the likely successor to visionary founder and CEO Masayoshi Son. But less than two years after taking the job, Arora resigned. As he explained it, Son told him he was going to keep running the show for another five to 10 years.

Roughly 10 months before leaving SoftBank, Arora said he was buying more than $480 million worth of stock in the Japanese conglomerate, which he said involved taking an “enormous risk” reflecting his confidence “about the future” of the company.

While that’s all firmly in the past, Arora said that over the years, he’s “scavenged” different leadership qualities from each of his mentors, including an appetite for risk from Son.

“It’s about finding role models for certain behaviors and wanting to understand what makes them really successful,” he said. “That’s my model.”

Investors weren’t completely sold on Arora when he joined Palo Alto in 2018, said Joseph Gallo, an analyst at Jefferies. He was a skilled and experienced businessman but some worried that he hadn’t created a notable product or founded a company like many of his industry peers, said Gallo, who recommends buying Palo Alto shares.

Arora made up for it with an ability to spot trends ahead of the curve, Gallo said. That included investing aggressively in a transition from on-premises technology to the cloud and then recognizing early the power of AI.

In his first few years at the company, Arora made numerous acquisitions for a total of about $3 billion, helping Palo Alto penetrate the cloud security space as more businesses were moving their workloads to Amazon Web Services, Microsoft Azure and Google’s cloud.

“Every company wishes they were in Palo Alto shoes, where they could actually offer all these different products,” said Andrew Nowinski, an analyst at Wells Fargo who has a buy recommendation on the stock. “It’s very difficult. You’re not going to see many vendors like Palo Alto.”

With its expansion into identity management, Palo Alto is going big in a space that’s viewed by experts as a key spending area for IT in the coming years.

“You can’t slow down your spending because the hackers aren’t slowing down,” Nowinski said. “That’s your growth driver.”

Ofer Schreiber, senior partner and head of YL Ventures’ Israel office, said Palo Alto has helped take an extremely fragmented market, consisting of lots of point solutions, and created a centralized vendor for clients.

According to a joint report from IBM and Palo Alto published in January, the average organization uses 83 different security products from 29 separate companies.

“From the customer’s perspective, it’s much more convenient dealing with with one vendor with multiple products tightly integrated,” Schreiber said. “You can’t really be just a one-product company.”

Still, Arora is in untested waters with CyberArk.

Palo Alto’s shares dropped on all five days following the announcement of the deal. It’s the first time at Palo Alto that Arora has led a multibillion-dollar purchase, and he now faces the execution challenges of integrating thousands of new employees.

Analysts at KeyBanc lowered their rating to the equivalent of hold from buy, due partly to concerns about a lack of “meaningful synergies” in the product offerings and a view that customers would prefer an “independent vendor solely focused on identity.”

But TD Cowen’s Shaul Eyal still recommends buying the shares. He said that what’s made Arora successful is his “relentless focus on execution” and his strategy of betting on sizeable markets where Palo Alto can quickly scale and become the leader or runner-up.

That, and his ability to bundle.

“It’s all about upsell,” Eyal said. “Every other second, third, fourth module you’re selling to an existing customer flows straight to the bottom line.”