A BTO vulnerability is a flaw in a copy prevention system that makes a copy of the product where the system has been circumvented Better Than the Original (ie an official copy) in some way.

This results in an alternative to the original product that is more desirable, thus defeating the object of the copy prevention by creating more customers for the alternative product, including some who may otherwise have bought the original.

There are three common examples of this:

1. The user-interactive copy prevention used in software in the early 90s (for example asking a user what a certain word within the manual was, given that only someone with an original copy of the software would have the manual). However, this meant that a copy of such a game which has had the copy prevention removed has two advantages:
   1. If the user loses the manual, the game is still playable.
   2. The user does not have to go through the inconvenience of looking up something in the manual every time they want to play the game.
2. The music industry's current policy of corrupting Audio CDs so that they play fine on CD players but cause problems if played in a computer CD-ROM drive, ranging from not playing to causing a computer failure. The result of this is that people who want to play the CD on their computer are instead buying an uncorrupted copied CD instead of the corrupt original or downloading the equivalent MP3s from the Internet. This list shows which CDs in the UK have been identified as corrupt.
3. Some programs require that the program's original CD be in the CD-ROM drive for the program to work. However "no-CD" cracks circumvent this requirement, providing the following user benefits:
   1. If the cd is lost or damaged, the program is still usable.
   2. The user no longer has the inconvenience of having to find the CD-ROM and tie up the CD-ROM drive.
   3. The program starts loading straight away (without asking for a CD) and loads quicker because hard drives are much faster than CD-Roms. Even if only a small amount of data is read from the CD, it can take a few seconds for the disc to spin up.

This is most frequently found in computer games software.