diff --git a/panda/src/glstuff/glShaderContext_src.cxx b/panda/src/glstuff/glShaderContext_src.cxx
index 200e39004d..d61d75beb6 100644
--- a/panda/src/glstuff/glShaderContext_src.cxx
+++ b/panda/src/glstuff/glShaderContext_src.cxx
@@ -890,6 +890,7 @@ reflect_uniform(int i, char *name_buffer, GLsizei name_buflen) {
 
         // Add it once for each index.
         for (bind._index = 0; bind._index < param_size; ++bind._index) {
+          bind._id._seqno = p + bind._index;
           _shader->_mat_spec.push_back(bind);
         }
         _shader->_mat_deps |= bind._dep[0];