Another reader's query

Here's another question from Andrew Clay (Head of IP, Hammonds LLP). It relates to the UK's Registered Designs Act 1949, section 19(1), which states

"Where any person becomes entitled by assignment, transmission or operation of law to a registered design or to a share in a registered design, or becomes entitled as mortgagee, licensee or otherwise to any other interest in a registered design, he shall apply to the registrar in the prescribed manner for the registration of his title as proprietor or co-proprietor or, as the case may be, of notice of his interest, in the register of designs".

Andrew asks:

"Section 19(1) RDA - what is all this about? You shall register but what happens if you don't? You can't sue for infringement (section 7) but the section 19(4) restriction on who can deal has gone. Do you lose out to a subsequent bona fide purchaser for value without notice or not, as for patents or trade marks? Why aren't the provisions clear on what is an important point, especially following umpteen revisions of the RDA? What could possibly be the policy reason for this difference in treatment?"

Any thoughts, folks?