One of the requirements for a UK registered design is that the design is new and has individual character.
A design can only be protected to the extent that it is new i.e. that no identical design has been made available to the public within the relevant date.
In addition the design must have individual character i.e. the overall impression of the design on the informed user must differ from that produced by existing designs made available to the public before the relevant date.
One important consideration when determining whether a design has individual character is the amount of freedom the author had with the design, various functional items for example have to contain certain features or be a certain shape etc.
The informed user is one with knowledge in the relevant sector. The relevant date ignores certain allowed disclosures, namely: 1) where the design could not reasonably have become known before the application date 2) where a disclosure was made under confidentiality or 3) where disclosure is made within 12 months of the application date.