RIPK3 and neoplasm: We first confirmed that germline Ripk3−/− mice in our animal facility maintained under specific‐pathogen‐free conditions were free of any signs or symptoms associated with particular disease phenotypes as previously reported.[18a] Then we observed that over full mice lifetimes, RIPK3‐deficient mice showed a reduced survival rate accompanied by a higher incidence of spontaneous tumor formation in various tissues, including the liver and lungs (Figure 1A).