I Don't Believe in Imaginary Property writes "The authors of the Zeus malware have added an end-user license agreement to their product. The buyer is, of course, permitted to infect as many computers with Zeus as they please, but they have no right to distribute it for 'any business or commercial purpose not connected with this sale,' and they can't examine the source, use it to control non-Zeus botnets, or send it to anti-virus companies. Oh, and they commit to paying for future upgrades, too — wouldn't Microsoft love to be able to add that term to their EULA. While it seems silly to imagine Zeus's authors going to the authorities for violations of this EULA, if they're anything like the Russian Business Network, they probably have an extra-judicial means of contract enforcement named Ivan. That said, this is by no means the first EULA-encrusted malware."