I can tell you through my Job that UPS will not allow you to open your packages and inspect them prior to signature.
Then when you find something wrong and file a claim it is always insufficient packing material so they are not liable.
Good luck
I work for UPS (almost 8 years) and I have to say that you are right, but
UPS Frieght
But UPS Frieght, even though it is owned by UPS (was Overnight), it is treated as a seperate part of the company. Also since the box did not appear to have damage, then the liability might go against Sherman.
I understand that some packages do get damaged, but we try our best to keep that from happening. Some of it is UPS' fault (even thought they may not say it), but many times it is the shipper's fault. I have personally seen companies quickly load a box (little to no packing material), use very little tape, and toss it (literally) to a UPS driver to be picked up.
They expect this poorly packaged box to go across the crountry and not get damaged, when they know it will have to be handled by many people in the process.
I am truly sorry for your damaged parts if it was UPS' fault and I hope you can get it resolved quickly.