Not invented here (NIH) is the tendency to avoid using or buying products, research, standards, or knowledge from external origins.
[1] The reasons for not wanting to use the work of others are varied, but can include a desire to support a local economy instead of paying royalties to a foreign license-holder, fear of patent infringement, lack of understanding of the foreign work, an unwillingness to acknowledge or value the work of others, jealousy, belief perseverance, or forming part of a wider turf war.
[2] As a social phenomenon, this tendency can manifest itself as an unwillingness to adopt an idea or product because it originates from another culture, a form of tribalism[3] and/or an inadequate effort in choosing the right approach for the business.
The opposite predisposition is sometimes called "proudly found elsewhere" (PFE)[5] or "invented elsewhere".
A 1982 study by Ralph Katz and Thomas J. Allen provides empirical evidence for the "not invented here" syndrome, showing that the performance of R&D project groups declines after about five years, which they attribute to the groups becoming increasingly insular and communicating less with key information sources outside the group.