Jeffrey Smith, CEO and chief investment officer at Starboard Value LP.David Paul Morris | Bloomberg | Getty ImagesStarboard Value, the activist fund run by Jeff Smith, has taken a sizable stake in graphics-design firm Autodesk and has spoken with the company's board in recent weeks over a number of serious concerns involving its disclosures around an internal investigation that led to the ouster of its chief financial officer.Starboard's stake is valued at roughly $500 million, according to peop...