(1) A third party may intervene in invalidity proceedings if a non-appealable decision has not yet been taken in respect of the application for the determination or declaration of invalidity and if that third party can substantiate that
1. proceedings for infringement of the same registered design are pending against them or
2. they have been requested to cease and desist from an alleged infringement of the same registered design.
The intervention may be declared within three months from institution of the proceedings referred to in sentence 1 no. 1 or from receipt of the cease and desist request referred to in sentence 1 no. 2.
(2) Intervention is effected by filing of a request; sections 34 and 34a apply accordingly. If the intervention occurs in the appeal proceedings before the Federal Patent Court, the intervening party is given the status of an appellant.