Although borderzone brain infarcts lack a uniform definition and are difficult to define because of significant variability in cerebral vascular supply, they are presumed to be related to haemodynamic factors such as carotid obstruction. In this study on 813 first-ever stroke patients, borderzone infarcts were defined not only according to the currently used 'classic' definition, but also taking into account the variability in cerebral vascular supply areas. Borderzone infarcts, defined in either way, were compared with remaining superficial infarcts with respect to vascular risk factors. We identified 5 patients with 'classic' borderzone infarcts (slit-like infarcts along the borders of the different vascular territories). Four of these had a carotid occlusion, which was significantly more frequent than in remaining superficial infarcts (odds ratio, OR: 15.52; 95% confidence interval, CI: 2.01–119.68; p = 0.008). Borderzone infarcts defined accounting for variability in vascular supply did not show any difference with regard to specific risk factors when compared with remaining superficial infarcts. Chronic obstructive pulmonary disease (COPD) and especially COPD combined with diabetes mellitus was more frequent among borderzone infarcts defined in either way (adjusted OR 21.3, 95% CI, 3.80–120, p = 0.0004, and adjusted OR 12.0, 95% CI 2.26–63.6, p = 0.003, respectively); this factor may increase the risk of infarction in case of reduced flow or thrombo-embolism. In conclusion: 'classic' borderzone infarcts are associated with ipsilateral carotid occlusive disease; this association is lost when expanding the definition, although COPD combined with diabetes mellitus then appears as a new risk factor associated with borderzone infarcts.