One of the biggest selling points for the upcoming Moto X is the ability to customize the phone. You can choose different front and back covers, accents and even have the phone engraved with a custom signature. But it turns out that there are some words that Motorola would rather you not say.

David Pierce of The Verge got to try out the Moto Maker before its release and after getting to the engraving option, found out that while you can certainly type most words to appear on the back of your phone, there are a number of words that aren’t allowed. Here’s a list of words that can’t be engraved on your Moto X:

“Apple”

“Google”

“Samsung”

“DROID”

Swear words

Apple makes sense because of the trademark violations, but why not Google? Motorola is a “Google Company.” I guess that’s reserved for Nexus devices — but we haven’t seen one of those in awhile. DROID is licensed by Verizon and owned by Lucasfilm so that’s a no go too. Here’s what you can engrave on your Moto X, and it’s a little weird:

“Powered by OS X”

“iPhone”

“Facebook”

“WebOS Forever”

It’s a little strange that Motorola made sure to decline names like Apple and Google, but didn’t do so for iPhone and Facebook. Either way, these engravings are permanent, so if you’re planning on getting Moto X and having it engraved — just don’t, unless you’re absolutely sure you won’t regret that decision in the next couple of months.

[via The Verge]