The J. M. Smucker Company

Smucker makes Uncrustables frozen peanut butter sandwiches on purpose-built cutting-and-sealing machinery that shapes, fills, and crimps a sealed crustless sandwich at a geometry that standard food-manufacturing equipment cannot produce. Because each production line is built entirely around that one geometry, the factories accumulate years of process depth in seal integrity and temperature control that only works for this product — and a competitor wanting to match it would have to invest in the same single-purpose machinery while accepting the same risk of being stuck with it if demand fell. That stranded-capital exposure is exactly what has kept rivals out, and in the meantime Smucker has used that head start to negotiate the freezer shelf positions that grocery chains assign on their own timetable through formal planogram resets — meaning a new entrant cannot simply buy its way onto the shelf even after solving the engineering problem. The one ceiling Smucker cannot control is that same freezer shelf: grocery purchasing departments decide how many facings Uncrustables gets, so the factory can have spare capacity and still be unable to grow until a retailer chooses to run a reset.