As of IDA latest public release (ie. v5.4.0.921),
following file+folders are watermarked...
/ida.key
/ida.wll
/loaders/*.*
/procs/*.*
Above info is gathered by looking at ida.key date.
Moreover no file is packed or obfuscated in any way,
this will allow to analyze IDA itself.
The registered user name is tagged in MS-DOS STUB portion of the watermarked executables.
So there are lot of possibilities to make a cracked version of IDA.
Key Pointers
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- Possibility to generate legitimate ida.key files,
// 'coz recently we seen awesome winrar solution
- Compare 2 identical version/edition of IDA to findout exect differences