The precise molecular mechanisms underlying angioedema attacks in cases of C1‐inhibitor‐deficient hereditary angioedema (C1‐INH‐HAE), angiotensin‐converting enzyme inhibitor‐induced angioedema (ACEi‐AE), and mast cell‐/histamine‐mediated angioedema (Hist‐AE) are not well understood. Here, SERPING1 is linked to hereditary angioedema.