If owner is changed, phenotips will add the previous owner as collaborator. This is not immediately clear to the user, as it initially shows new owner and no collaborator. Once user refreshes the form, the newly added collaborator appears.
Step to reproduce:
open patient record; click on Modify permissions button; assign new owner; click on update; the patient record form will show the new owner and no collaborator (before refresh.jpg)
refresh the page and notice the added collaborator (after refresh.jpg)