As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
AIRCRAFT WAS GROUNDED: AN EMERGENCY WAS NOT DECLARED DUE TO: CAPTAINS PRIMARY FLIGHT DISPLAY (PFD) FLASHED INTERMITTENTLY SHORTLY AFTER TAKEOFF. BOTH AMBER SPEED AND ALTITUDE DISPLAYED ON CAPTAINS PFD. AIRCRAFT AIR INTERRUPTED BACK TO AND LANDED SAFELY AT DEN. (OPEN).