The U.K. financial regulator has dropped 100 investigations without action over the past three years, but compliance should expect a refocus of resources rather than a retreat from enforcement.

The Financial Times reported the cull of “dead end” cases on Jan. 2. An official at the Financial Conduct Authority (FCA) told the FT the regulator is “committed to carrying out fewer, more focused investigations.”

Ruth Prickett graduated from Cambridge University with a BA hons in History and has specialized in business and finance journalism for the past 20 years. She was editor of Financial Management, the magazine...