Complex sentence: These were free of Sauron's influence, as he did not have a hand in their making; however they were still forged by Celebrimbor with the arts taught to him by Sauron and thus were still bound to the One Ring.
Split into simpler sentences: These were free of Sauron's influence, as he did not have a hand in their making. However, they were still forged by Celebrimbor with the arts taught to him by Sauron and thus were still bound to the One Ring.