I'm pretty sure you will not be able to "raise the serial number" by acid etching because that only works for steel that has had the serial numbers stamped in.
All Yarboroughs serial numbers are engraved to avoid the stress risers caused by stamping and engraving has very little impact on the grain structure underneath.

How the serial numbers were ground off will determine how strong the blade remains. All tool steels in this class are to one degree or another notch sensitive.
If the knife is wrecked you may as well carry it until it can't be carried but if your life depends on a knife, get a good one that isn't f*cked up.

Wow, what a damn shame to deface a knife like that. I would love to have one, and then you have people with no regard and screw it up...

Damn shame...

Confirmed with the Chris Reeve shop that serial numbers are engraved in prior to heat treat which means all the heat treat soaks would erase what minimal pressure marks the carbide cutter may have left.
Nothing would show up in an acid etch.
If someone can prove me wrong, please advise.

Engraving is much lighter on the metal than stamping serial numbers in already heat treated steels like firearms or motor cases made from other metals.

Also check with the Chris Reeve shop to see of any of you qualify for a Military or Law Enforcement discount, if interested in getting a knife.

For those who are interested.
I recovered another Yarborough in another meth lab. This one actually has the SN intact! I am out on sick leave for a couple of weeks but I will work on tracking down the owner while I am recovering.
Update to follow.

Kyle, you can send me a private message with the serial number I can work on it while you are out.
Or have someone stop by the courts complex at room 436.
CB

Great news!
I spoke to the owner via email today! He is active duty so I will not be posting any further details about him.

Hopefully I can get this returned tomorrow.

Kyle, tell me it's one of my clients so I can move to withdraw!:D

LOL! I am sorry to tell you it isn't.

I just wanted to add that the knife has been returned to its rightful owner.
I met with him today. His was a cautionary tale of drug addiction and vindictive spouses.

Thank you to everyone here and at the Special Forces museum for their help!

ETA: He wasn't addicted to anything. His former spouse was.

Nice work on your part to get it back to him!

Well done!