This is a phase 2, multicenter, single arm, 2 cohort study to assess the safety, efficacy and pharmacokinetics of AMG 337 in MET amplified Gastric/esophageal adenocarcinoma or other solid tumors. Approximately 140 subjects will be enrolled to either Cohort 1 (subjects with MET amplified G/E adenocarcinoma with measurable tumor) or Cohort 2 (subjects with MET amplified solid tumors with measurable tumor/up to 10 subjects with MET amplified G/E adenocarcinoma with non-measurable tumor/up to 10 subjects who have received prior MET antibody therapy). All subjects will self-administer AMG 337 300 mg daily until disease progression or other protocol specified end of treatment criteria is met.