PEN

Penumbra, Inc

A medical device company that builds tools to remove blood clots from the brain and blood vessels, helping treat strokes and other vascular emergencies. Its Penumbra System and Indigo System use vacuum suction to pull clots out through thin catheters. Founded in 2004 by a neurointerventionalist and a former real estate lawyer who were college roommates, the name comes from the Latin for "almost shadow" — the lighter edge of a shadow, and the term for brain tissue around a stroke that is damaged but not yet lost.