v2021.1
The 'Show Parent Company' option in General Settings allows you to more easily manage your companies by creating a nested company structure where a parent company can maintain multiple child companies.
A parent company can have multiple child companies, but a child company can only have one parent company. A parent company cannot have its own parent company and a child company cannot be set as a parent company. A deleted parent company will appear as read only in the child company's details and it cannot be changed or deleted. Please note that a company cannot be both a Supplier and a Parent Company.
Additionally, a Work Manager user will be able to start work items for both parent and child companies for a parent company contact; however they will only be to start a work item for a child company for a child company contact.
The Contacts Card in Work Manager for work items running against a parent company will show the contacts of that parent company, but will not show any child company contacts, however work items running against a child company will show the contacts of that child company as well as of the parent company.