The invention relates to anti-HER1 antigen binding proteins, e.g. anti-HER1 antibodies, that bind to the beta-hairpin of HER1, methods for selecting these antigen binding proteins, their preparation and use as medicament.本發明係關於結合至HER1貝他-髮夾之抗HER1抗原結合蛋白(例如抗HER1抗體)、選擇該等抗原結合蛋白之方法、該等抗原結合蛋白之製備,及其作為醫藥之用途。