Before Armis and Wiz were worth billions, Rappaport and Dibrov wrote each other $100,000 checks
The two cybersecurity entrepreneurs first met in the IDF’s elite Unit 81 before becoming early investors in each other’s startups, which went on to produce two of Israel’s biggest technology exits.
In December 2015, Yevgeny Dibrov was leaving Microsoft to start his own cybersecurity company when he asked his former commander and friend Assaf Rappaport to be his first investor. Rappaport agreed, but made the arrangement reciprocal; he would write the first check into Dibrov's new company if Dibrov agreed to be the first investor in Rappaport's next venture.
Rappaport's check was $100,000. Years later, when he co-founded Wiz, Dibrov returned the favor with a $100,000 first check of his own. Nearly a decade later, those two modest investments connect two companies that were ultimately acquired for a combined $39.75 billion, with Armis being purchased by ServiceNow for $7.75 billion in 2026, while Wiz was bought by Google for $32 billion in 2025.
The unusual arrangement offers a glimpse into the long relationship between two entrepreneurs whose companies became two of the biggest cybersecurity success stories to emerge from Israel. The details of the reciprocal investments were reported in a recent Fortune feature on Dibrov.
Their relationship began years before either became an entrepreneur. According to Fortune, Rappaport first heard about Dibrov in 2007, when Dibrov was 19 and serving in the Israel Defense Forces’ elite Unit 81. A friend repeatedly urged Rappaport, then 24, to meet the younger soldier, describing him as someone whose abilities were being wasted.
Rappaport eventually spoke with Dibrov by phone and decided he wanted him in his unit. He became Dibrov’s commanding officer, and the two developed a relationship that extended beyond their military work.
After leaving the military, Rappaport co-founded Adallom, a cybersecurity company that protected corporate data stored in cloud applications. Microsoft acquired the company for $250 million in 2015. Dibrov joined Adallom in 2012 as its first employee and eventually handled business development across Europe, the Middle East and Asia.
When Dibrov left Microsoft in December 2015, he went on to establish Armis with Nadir Izrael. The company initially focused on identifying and securing connected devices inside organizations, eventually developing into a broader cybersecurity platform.
Armis’ first funding round, in January 2016, valued the company at just $11 million after the investment. According to Fortune, Dibrov and Izrael were still pitching investors without even having a term sheet when they raised $5 million.
The company would eventually follow a dramatically different trajectory. Insight Partners acquired Armis in 2020 at a valuation of roughly $1.1 billion, while Dibrov and Izrael continued to run the business independently.
By the time ServiceNow acquired Armis for $7.75 billion in April 2026, the company had grown to approximately 950 employees and more than $300 million in annual recurring revenue. The transaction was the largest acquisition in ServiceNow’s history and one of the largest startup exits in Israeli technology.
Dibrov and Izrael received roughly $930 million combined, according to Fortune, and both remained with ServiceNow. Dibrov became general manager of the Armis business, while Izrael took the role of group vice president of product and engineering.
