A version of this article first appeared in CNBC’s Inside Wealth newsletter with Robert Frank, a weekly guide to the high net worth investor and consumer. Sign up to receive future editions, straight to your inbox.

Jeff Bezos has been making headlines for his big-ticket purchases — from a $165 million estate in Los Angeles and a $177 million property on Miami’s Indian Creek to his $500 million yacht.

Yet, Bezos’ biggest recent buying binge may be in artificial intelligence, through his family office.

All of the investments made this year by Bezos’ family office — called Bezos Expeditions — have been in artificial intelligence, according to exclusive data provided to CNBC by FINTRX, a private wealth intelligence platform. While the amounts he invested are not disclosed, Bezos Expeditions participated in funding rounds totaling more than $1 billion.

In January, the Amazon founder and executive chairman invested in the $73.6 million Series B round of Perplexity AI, an AI-powered search engine company. He also invested in a $63 million follow-on round in April. The value of Bezos Expeditions’ January investment likely doubled by April, since the company says its valuation soared to between $2.5 billion and $3 billion.

In February, Bezos Expeditions invested in Figure AI, the humanoid-robot company that also counts Nvidia and Microsoft as investors. The venture round totaled $675 million.

In July, he invested in a $300 million Series A round of Skild AI, which is focused on making AI systems for machines and robotics devices.

Bezos Expeditions has always tilted heavily toward tech. Fully 70% of his family office investments are in technology, according to FINTRX. The next-biggest category is consumer goods, at 16%, followed by financial services and manufacturing, both at 13%. But now, his primary focus seems to be AI.

In a podcast interview in January, Bezos said AI tools are “not inventions, but discoveries” that will have profound effects on technology and change. “These powerful tools are much more likely to help us and save us even than they are to unbalance, hurt us and destroy us,” he said.

Bezos has plenty of company among family offices. According to the UBS Global Family Office Report, AI is now the favorite investment category for family offices. More than three-quarters, or 78%, of family offices surveyed plan to invest in AI in the next two to three years — the most for any category.

Amazon has also been ploughing money into AI. The company plans to invest more than $100 billion in data centers over the next decade and invested $4 billion in Anthropic, the AI safety and research firm.

Bezos recently filed a stock-sale plan to unload another $5 billion worth of Amazon shares this year, after selling $8 billion worth earlier this year. With more than $13 billion in cash, Bezos will now have even more money to bet on the AI boom.