SquareOne, a secretive Campbell, Calif. artery ostial stent company (no Web site), has raised $8 million in a third round of financing as it looks to launch initial trials, VentureWire reports (sub required).

Three Arch Partners led the round, contributing $4 million, VentureWire reported. Onset Ventures put in $3 million, while Finistere Ventures and existing angels contributed $500,000 each.