Everpure, Inc. P

The business

Pure Storage sells all-flash data storage arrays, refrigerator-sized boxes packed with flash memory modules Pure designs itself and software called Purity that runs them. For a decade the buyers were corporate data centers replacing hard-drive arrays, and Pure won them with a promise called Evergreen: it upgrades your storage in place forever instead of forcing a rip-and-replace cycle every few years. That promise, plus flash modules Pure designs rather than buying off the shelf, creates switching costs. Once a customer is on the Evergreen subscription, leaving means re-buying everything. Increasingly the product is sold as a service, Evergreen//One, billed like electricity rather than as capital equipment. The new chapter, and the reason the stock doubled off its 52-week low, is that the largest cloud operators are now buying Pure flash to replace the spinning hard drives in their data warehouses.