In this paper we present Egas, a web-based platform for biomedical text mining and collaborative curation. The web tool allows users to annotate texts with concept occurrences as well as with relations between concepts. Annotations may be imported together with the documents using one of the accepted input formats, or may be added during the annotation process, either manually or by calling a document annotation service. Users can further inspect, correct or remove automatic text mining results, add new annotations, and export the results to standard formats. The tool is available at http://bioinformatics.ua.pt/egas and is compatible with most recent versions of Google Chrome, Mozilla Firefox, Internet Explorer and Safar