A Neapolitan banker invented investing that rewards outliving your friends

Lorenzo de Tonti, a banker working in France in 1653, is popularly credited with a financial structure so strange it still unsettles people three and a half centuries later. Subscribers pool money into a shared trust. Each receives a periodic payout for as long as they live. When a member dies, their share doesn't go to an heir — it gets redistributed among the survivors, so each remaining payout grows larger as the group shrinks. The last person alive often inherits what amounts to the whole pool.

Governments loved it for a simple reason: it let them borrow large sums up front while spreading the repayment obligation across an unpredictable number of years, tied to when subscribers happened to die rather than a fixed schedule. Tontines helped finance public projects and government debt across Europe through the 18th and 19th centuries.

The structure eventually curdled in the United States. Life insurers sold tontine-linked policies aggressively in the late 1800s, with sales practices opaque enough that the 1906 Armstrong Investigation in New York effectively ended the American tontine industry over conflicts of interest between insurers and policyholders.

The idea never really died, though. European insurers still issue tontine-based products today, and in 2019 EU pension regulation explicitly made room for the mechanism again — proof that turning survival itself into the return isn't a scam waiting to happen. It's a genuinely unusual way to price a very old uncertainty: nobody knows how long they'll live, and someone has to hold that risk.