Extend

In document AI, nearly every pitch leans on a wall of logos the startup controls. Extend has the thing those rivals mostly can't show: a customer willing to say it on its own letterhead. Flatiron Health states publicly that it piloted Extend, signed on, and is scaling biomarker extraction — outside-the-room proof in one of the most demanding regulated workflows there is. The rest of the foundation holds up too: a $17M seed-and-Series-A led by Innovation Endeavors, a Y Combinator Winter 2023 stamp, and a product that reaches well past raw parsing into workflows and evaluations. Seventy-four public sources, five partner lenses, one day — cited, never spun. What the public record cannot show is whether the economics underneath are software or pass-through, and that one unseen layer carries the whole case. The teardown settles it. Read it before the next round prices the window shut.