Key legal question
Whether Helvetia Nostra had standing to challenge the building permit based on Art. 75b BV and transitional rules.
Extracted holding
Yes. Authorized nature-conservation organizations may challenge building permits for alleged violations of Art. 75b BV and its transitional/implementing provisions.
Extracted reasoning
The second-home cap serves a federal conservation task; under Art. 12(1)(b) NHG, qualifying organizations may attack permits alleging breach of Art. 75b BV. The cantonal court erred in denying standing.