Technology dominates financial services so California is leading the deal making built on its strong universities.

For financiers working in New York City, London, Frankfurt or Hong Kong, California and Silicon Valley can seem of peripheral interest unless your work involves floating or selling technology companies.

But a decade after online payments provider PayPal filed to float on the Nasdaq stock exchange, the established financial services firms whose attention is elsewhere are missing some potentially seismic changes.

Just as the internet, data analysis tools and mobile devices have affected other industries, so traditional financial services are…