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 DECLARED AND THE AIRCRAFT RETURNED TO PHL DUE TO THE FLIGHT CREW REPORTING THE LOSS OF THE GREEN HYDRAUILIC SYSTEM QUANTITY SHORTLY AFTER DEPARTURE. THE AIRCRAFT LANDED SAFELY AT PHL WITHOUT FURTHER INCIDENT. (OPEN)