TeacherLock debuted later that year to strong interest from school districts nationwide. Early adopters included a Kansas district outfitting 50 doors and a major Texas district ordering 1,500 units. By late 2018, the company had shipped thousands of devices, with Boston 25 News highlighting the Emmas’ story and the device’s simplicity and compliance advantages.

In 2019, TeacherLock received its U.S. trademark (Reg. No. 5818797) and was soon recognized by ALERRT and other safety organizations for its intuitive, life-saving design. On January 4, 2022, the U.S. Patent and Trademark Office granted Patent No. 11,214,986 for its emergency deadbolt mechanism and first-responder access feature. A second patent for its single-action unlocking system followed in January 2024.

Building on success in schools, Defcon introduced TeacherLock II, featuring a patent-pending “shark-fin” adjustment for faster installation and enhanced precision. In 2023, the California Office of the State Fire Marshal formally approved TeacherLock II for its Building Materials Listing, and by mid-2025, both models achieved 60-minute fire resistance ratings, expanding their use to fire-rated doors in schools, hospitals, and offices.

The innovation extended beyond education. Under the SaberLock brand, the company adapted its technology for commercial and government use — including a nationwide rollout with a major U.S. retailer across 1,800 locations. TeacherLock also earned approval from multiple state fire marshals, the U.S. Coast Guard, and received recognition as Massachusetts Manufacturer of the Year (2020) for pivoting production to respirators during COVID-19.

From a principal’s concern to a patented, life-saving device now trusted across North America, TeacherLock represents a simple truth: in an emergency, seconds matter — and safety should never depend on a key.