Warren Buffett (Berkshire Hathaway)’s Dassault Falcon 20
After years of mocking executives for their corporate jets, Buffett bought a used Falcon 20 for $850,000 in 1986 and named it 'The Indefensible' (Charlie Munger had proposed 'The Aberration'). He later traded up and renamed the jet 'The Indispensable', then bought the whole of NetJets in 1998 for $725 million.
Sources: forbes.com · finance.yahoo.com
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Elon Musk
Gulfstream G650ER · $70M reported
The tail number encodes his 28 June birthday, and the G650ER became the most-tracked business jet in the world after a student-run account began posting its movements in 2020. Musk also operates two Gulfstream G550s and was reported to have ordered a G700 in 2022. The jet's public tracking led to a 2022 policy change on Twitter/X that banned real-time location sharing.

Jeff Bezos
Gulfstream G650ER · $65M reported
Bezos has owned two G650ERs through a Seattle holding company and was reported in late 2024 to be selling the older one (a 2015 airframe) for just under $39 million after taking delivery of a new Gulfstream G700 reported at around $80 million. His arrival at the COP26 climate summit by Gulfstream drew wide media attention in 2021.

Bill Gates
Gulfstream G650ER (two) · $70M reported
Gates is reported to own two G650ERs, both 2018 builds based at Boeing Field in Seattle, plus access to Challenger 350s via a NetJets arrangement. He has called private flying his 'guilty pleasure' and says he offsets his emissions by funding direct-air-capture and sustainable fuel ventures.