An original design manufacturer is a company that designs and manufactures a product, in contrast to "OEM" which only manufactures a product.
Post-2016 Nokia phones (HMD) is an example of a firm which relies on original design manufacturers.
In late 2019, it switched from relying on only one original design manufacturer to multiple original design manufacturers.
[1] Original design manufacturers create their own intellectual property and are very proactive in patenting it.
Most of their patents are filed in the US, China, and Taiwan.