Sneddon's syndrome is a rare disease characterized by cerebrovascular events and livedo racemosa. There are often autoimmunological comorbidities, especially antiphospholipid antibody syndrome. The underlying pathophysiology is still not fully clarified. A causal therapy does not exist. The reported case shows a patient with a thrombophilic form of Sneddon's syndrome with the main symptoms of headache and thromboembolic events. Symptoms, laboratory parameters, histology and differential diagnoses are explained.