Proposal to allow the use of manufacturer logos in the internal structure of optical components and/or in the outer lens within the apparent surface of a signalling lamp.

Update to remove direction indicator lamps of categories 11 and 12 from the list of lamps required to fulfill n-1 failure requirements of UN R50. Restoration of an extra requirement for reversing lamps found in UN R23 but unintentionally omitted from the original text.