The OEM project is identical to the Main project, except that:
- the manufacturer code of all data is changed.
- the OriginalManufacturer attribute in the Hardware properties is set to the manufacturer ID of the original manufacturer (in our case, Siemens).
- Note: If, for any reason, the Main project was started with the manufacturer code of KNX Association, then the OriginalManufacturer attribute will be left empty when creating an OEM project.
- Registration data is removed, the product is set to unregistered.

After creating the OEM project, the following still has to be done:
- Make sure that the unique keys of the OEM product do not interfere with any existing product(s) of the OEM customer (If it does, these unique keys must be changed);
- Hardware: SerialNumber and VersionNumber
- ApplicationProgram: ApplicationNumber and ApplicationVersion
- Product: OrderNumber
- The commercial data such as product name, order number and application program of the OEM product shall be changed. Modifications exceeding the items, as listed under Definition of OEM product, will be considered as Main and not as OEM.
- Export the OEM product for registration.
- An OEM product does not have to be tested, as the Main product has already shown compliance.