The least burdensome principle is a critical component in industry’s understanding of the proper role of government regulation, but this principle is the subject of considerable tension between the two sides. The latest report on the FDA’s performance under the fourth device user fee agreement noted that device makers raised the least burdensome flag in less than 0.5% of 510(k) submissions filed between February 2019 and April 2021, but the report gives the agency passing grades on its handling of those potentially controversial regulatory encounters.