It's hard to say, ask if you can take a screen shot of the warranty page and blur the number.
Blurring the number won't do, nowadays softwares can undo the blur or scrambled images, on the internet, there was this guy who did something bad, and scrambled a photo of him that he took, then later on, the Police found this person on the internet, unscrambled the photo with a software, bam, caught.