diff --git a/main.go b/main.go
index b2ef240..0046522 100644
--- a/main.go
+++ b/main.go
@@ -307,6 +307,8 @@ func licenseHeader(path string, tmpl *template.Template, data licenseData) ([]by
 		lic, err = executeTemplate(tmpl, data, "", "// ", "")
 	case ".ml", ".mli", ".mll", ".mly":
 		lic, err = executeTemplate(tmpl, data, "(**", "   ", "*)")
+	case ".hspice", ".spice", ".cdl":
+		lic, err = executeTemplate(tmpl, data, "", "* ", "")
 	default:
 		// handle various cmake files
 		if base == "cmakelists.txt" || strings.HasSuffix(base, ".cmake.in") || strings.HasSuffix(base, ".cmake") {