Adam Fuchs and his small team labored for years inside the National Security Agency on a system that would enable analysts to access vast troves of intelligence data and spot hidden patterns.
"We very much had a startup feel," Fuchs said. The team worked in an office at Fort Meade with ideas scrawled across whiteboards and old furniture scattered around.
Their work helped analysts identify terrorist groups. But the ordinarily secretive NSA did something else with the technology: Figuring that others could make use of it, too, the agency released it to the world for free.
And that was when those who had built the tool saw an opportunity. Half eventually left the...