The company buys its own shares on the market and retires them. Fewer shares remain — your slice of the business grows without you doing anything.
MoatLens tip: Buybacks are neither good nor bad; the price alone decides. Buying below intrinsic value quietly creates value for everyone who stays. Buying at record highs burns money. One pattern MoatLens watches for: buybacks that merely offset the dilution from employee shares. The share count then does not fall at all — but the money is gone regardless.
In MoatLens this explanation sits right next to the number — one tap away. And you see the ten-year trend instead of a single value.