Fidelity National Information Services, Inc. (FIS)

Fidelity National Information Services runs banks' core systems — the software that computes an account balance.

A bank's core system is the ledger of accounts, entries and interest, running around the clock with no right to be wrong. Hundreds of small banks do not build one themselves but rent it. Replacing such a system is a multi-year project with a risk of halting the bank, so the customer almost never leaves and revenue is predictable for years.

The flip side of that same durability is slowness: the systems are old, developing them is expensive, and new vendors offer the same on a modern foundation. The company sold most of its merchant payment processing arm to concentrate on banks. Risks: platform obsolescence, bank consolidation and the cost of modernisation. A dividend is paid and buybacks are active.