ARM Holdings

ARM Holdings designs the processor architecture used in 95% of smartphones, nearly all tablets, and billions of embedded devices. The company doesn't manufacture chips - it licenses intellectual property to semiconductor companies who design chips using ARM's instruction set.

This makes ARM a keystone technology platform - the architectural standard that enables an entire ecosystem. ARM created the technical infrastructure (instruction set architecture, design tools, software ecosystem) that thousands of companies build on, connecting otherwise independent chip designers and software developers through its platform.

ARM's keystone index is extraordinary - generating $3.23 billion in revenue while ARM-based chips represent $150+ billion in annual sales, with an impact-to-size ratio of perhaps 100:1.