Strictly speaking, I suppose, drilling and tapping it yourself would void the warranty but if it's done well my sense is that that's a pretty minor thing. I don't think the steel on the non-lock side is hardened so it should be fairly easy to drill and a tap is about 5 or 10 bucks, and even with the wrench it would be less than sending in to Emerson. I just got a CQC-15 and was a little disappointed that it's not drilled and tapped for left hand carry, but it's not a big deal. I noticed that the ZT version coming out is drilled and tapped every which way but loose.