> For the complete documentation index, see [llms.txt](https://docs.os.uk/os-downloads/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.os.uk/os-downloads/products/transport-network-portfolio/os-mastermap-highways-network-paths/os-mastermap-highways-network-paths-technical-specification/specification-changes.md).
# Specification changes
There have been small enhancements to the OS MasterMap Highways Network Version 2 to enable the release of new attributes and the capability to release change only updates (COU). This section will outline the main changes to the Path Network product. For changes to the Roads and RAMI products, please see their respective *Technical Specifications*.
## Features
1. PathLink and PathNode z values have been enhanced to reduce discrepancies when the path passes over a structure, for example, a bridge.
2. Added new feature type “HighwayDedication” to denote dedications of highways as defined in the [Highway Act 1980](http://www.legislation.gov.uk/ukpga/1980/66/contents) and [Countryside and Rights of Way Act 2000](https://www.legislation.gov.uk/ukpga/2000/37/contents).
3. As a result, there is a new code list, “DedicationValue”.
## Code lists, data types and enumerations
1. *March 2021* – The “ReinstatementTypeValue” code list has been updated with four new values added to include Scottish codes.
2. *March 2021* – The “SpecialDesignationTypeValue” code list has been updated with five new values added to include Scottish codes.
3. The “OperationalState” attribute on the Street features has introduced a new value “Addressing Only” into the “OperationalStateValue” codelist. The “NetworkReferenceLocation” has been further extended to accept additional geometry types, lines and polygons, in addition to start and end points. This affects “Maintenance”, “Reinstatement” and “Special Designation” and the information provided on their location for partial records. The “SpecialDesignationTypeValue” code list has been updated with multiple new values added. The “MaintenanceValue” enumeration has been updated with two values added.
## Schema changes
1. v2.1 RAMI schema is being released which will enable the code list and enumerations described above to be brought through.
2. v1.0 Highways Dedication schema has been introduced which defines the Highways Dedication feature.
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