diff --git a/fpdfsdk/fpdf_ppo.cpp b/fpdfsdk/fpdf_ppo.cpp
index 489d610..5c478cb 100644
--- a/fpdfsdk/fpdf_ppo.cpp
+++ b/fpdfsdk/fpdf_ppo.cpp
@@ -239,8 +239,7 @@
 
       uint32_t nEndPageNum = pdfium::base::checked_cast<uint32_t>(
           atoi(cbMidRange.Substr(nMid, nEnd).c_str()));
-      if (nStartPageNum < 0 || nStartPageNum > nEndPageNum ||
-          nEndPageNum > nCount) {
+      if (nStartPageNum > nEndPageNum || nEndPageNum > nCount) {
         return false;
       }
       for (uint32_t i = nStartPageNum; i <= nEndPageNum; ++i) {