Invented here is an opposite of "not invented here

Not Invented Here

Not invented here is a term used to describe persistent social, corporate, or institutional culture that avoids using or buying already existing products, research, standards, or knowledge because of their external origins. It is normally used in a pejorative sense, and may be considered an...

" that occurs when management of an organisation is uncomfortable with innovation or development conducted in-house. Reasons why this might be the case are varied, and range from a lack of confidence in the staff within the organisation to a desire to have a third party to blame in the event that a project fails. One effect of this version of "Invented Here" is that detailed knowledge of the innovation or development never passes to permanent employees, resulting in recurring additional expenditure and a lack of goodwill and bankable experience by employees.

One quotation that sums up the philosophy of Invented Here is "Gee, it can't be worth much if someone local thought of it first."