using CadImage cadImage = (CadImage)Image.Load(fileName); CadText text = new CadText(); text.DefaultValue = "Watermark text"; text.TextHeight = 40; text.FirstAlignment = new Cad3DPoint(300, 40); text.LayerName = "0"; cadImage.BlockEntities["*Model_Space"].AddEntity(text); CadMText watermark = new CadMText(); watermark.Text = "Watermark message"; watermark.InitialTextHeight = 40; watermark.InsertionPoint = new Cad3DPoint(300, 40); watermark.LayerName = "0"; cadImage.BlockEntities["*Model_Space"].AddEntity(watermark); cadImage.UpdateSize();