This document discusses how changing fields affects an inventor's ability to create novel and valuable inventions. It presents arguments that specialization within a field builds expertise but limits novelty, while changing fields fosters new ideas but lacks deep knowledge. The document hypothesizes that changing fields negatively impacts invention value but increases novelty. It also hypothesizes that collaboration or relying on published science in the new field can reduce the downsides of changing fields. The document describes using a natural experiment around non-compete laws in Michigan to study field-changing inventors' patents, analyzing the impact on invention novelty and value.