At the time of submission an author may have declared no potential conflicts of interest or an incomplete list.
The editor should communicate with the author and reader during the investigation.
The author's institution should be involved when the author denies an alleged conflict of interest or to inform an institution in cases of suspected misconduct.
A published article may need a correction or to be retracted, dependent on whether the editor considers the conflict of interest to have affected the peer review process or the article. Retraction should be consistent with COPE's retraction guidelines.