President of Jerusalem's Shaare Zedek Medical Center says WhatsApp co-founder Jan Koum’s donation, the largest gift in Israeli healthcare history, grew from years of trust, quiet ties and a shared vision for the capital's medical futureSarit Rosenblum|“I thanked him on WhatsApp. Nothing more natural than that,” he laughs.4 View gallery Prof. Jonathan Halevy (Photo: Alex Kolomoisky)At age 78, Halevy is celebrating on a private vacation with his wife Adina aboard a cruise ship sailing from Hong Kong to Tokyo, marking the largest donation ever made to Israel’s health system. The gift is set to fundamentally reshape medical care in Jerusalem. Behind the staggering sum lies an extraordinary story of modern philanthropy built on trust, extreme discretion, and long-term relationships that have now borne fruit.Koum, who values privacy to the extent that he refused to include ads in WhatsApp, has never met Halevy face to face. The complex negotiations lasted a full year and were conducted entirely through his foundation’s representative, Yana Kalika.“Jan Koum is a very discreet person,” Prof. Halevy says in an exclusive interview with Yedioth Ahronoth. “He gave a nanotechnology building to Tel Aviv University, and they awarded him an honorary doctorate. Before the inauguration ceremony he went into the university president’s office, shook his hand and left for the airport. He wasn’t at the ceremony. He reviewed every word of the contract with us, every detail had his approval, but there was still no direct meeting. He promised he would come for the cornerstone laying.”This historic donation, which will be transferred entirely into a restricted account for the new inpatient tower at Shaare Zedek, is the product of a relationship built over a decade. For Prof. Halevy, who led the hospital for 31 years and has served as its president for the past seven, and is also responsible for fundraising, it is nothing less than a life’s work.“It is certainly an extraordinary achievement to receive a donation of this kind, to earn the trust of such a person,” he says. “Even though the donation process took a year through official channels, the moment of signing itself was very emotional. I immediately called my wife Adina, Ofer Merin the hospital CEO, and my board chairman Ben Zion Hochstein. After 38 years at the hospital, this is a major milestone.”The agreement did not come overnight. The initial connection with the Koum family foundation began years ago through a smaller project.“Ten years ago, the foundation requested a proposal for a $15-million project,” Halevy recalls. “We competed with several hospitals. A representative of the foundation received us in the lobby of the Waldorf Astoria in Jerusalem. I presented a plan for a much smaller building of 24,000 square meters, including the pediatric wards and Neonatal intensive care unit, and we won the donation. Koum wanted to remain anonymous then, and the building is still called ‘Yekum Building,’ the name he chose to keep a low profile.”Since then, smaller donations continued regularly, from funding advanced catheterization rooms to special grants during the COVID-19 pandemic. According to Halevy, everything was based on delivery and trust.“When you keep your word to a donor, when you promise a project will be completed on time and it is, when you stay within budget and deliver naming rights as promised, trust is built,” he says. “Probably two months ago, when Koum turned 50, he rethought things and wanted his name on a hospital in Israel. This time there was no competition. He approached me directly.”