Husky Energy has stated that the "dropped object" was a hydraulic cylinder, part of the equipment that handles the "drill string" on the rig floor.
Operations on the rig are expected to be offline for a few days while the investigation is ongoing.
No further information was provided.
Husky Energy has suspended operations on the Henry Goodrich after a "near miss/dropped object" incident, according to a release issued Friday night by the Canada-Newfoundland and Labrador Offshore Petroleum Board.
The incident occured around 3 p.m. Thursday afternoon.
The statement said there were no injuries and Husky is taking the action as a precautionary measure to avoid similar incidents in the future.
The board's chief safety officer has met with Husky and operations will not resume until that official's safety concerns have been addressed.
No other details were provided.