diff --git a/lttoolbox/fst_processor.cc b/lttoolbox/fst_processor.cc
index b1f85d3..d4ff07d 100644
--- a/lttoolbox/fst_processor.cc
+++ b/lttoolbox/fst_processor.cc
@@ -2067,6 +2067,7 @@ FSTProcessor::quoteUnmerge(InputFile &input, UFILE *output)
           if (seen_reading) {
             u_fputc('/', output);
           }
+          if(it.mark != '\0') { u_fputc(it.mark, output); }
           write(it.content, output);
           seen_reading = true;
         }