Transport request does not contain any changes

Dear Experts,

Is it possible that a transport request (TR) is generated but it does not contain any changes?

I created a TR in Dev client some times back and ported it to Quality and the changes (which I feel were there) were working fine in ECT. Recently, we refreshed quality system (from production) and re-imported TR's to quality system and now if I see that TR, I find no changes/change objects within that TR. Is there any reason for it?

Or it's a bug?

Kindly Suggest!

Best Regards

Saurabh