Sam and the Ring

[Raynor]

Sauron apparently felt the ring, but was hindered in identifiying it due to the shadows he has put around as a defence

Originally Posted by The Tower Of Cirith Ungol, RotK

Immediately he felt the great burden of its weight, and felt afresh, but now more strong and urgent than ever, the malice of the Eye of Mordor, searching, trying to pierce the shadows that it had made for its own defence, but which now hindered it in its unquiet and doubt.