Luna Innovations Inc. announced that Carilion Clinic, its largest non-employee shareholder, has exchanged all outstanding convertible promissory notes of Luna, with a balance of principal and accrued interest equal to $6.2 million, for newly issued shares of Series A Convertible Preferred Stock of Luna. In 2005, Carilion Clinic invested $10 million in equity and $5 million in convertible promissory notes of Luna. The indebtedness accrued interest at 6 percent annually and had an aggregate bal...