Clean room reverse engineering

David Woolley forums at
Fri Dec 4 22:13:41 UTC 2009

Marc Whipple wrote:

> In any event, the concept of “reverse engineering” copyrighted material 
> is nonsensical under US law (and the law of many other countries.) If 
> you had enough access to it to reverse engineer it, you didn’t make a 
> new work, you copied an old one. If your new work otherwise is 

IANAL, but as I understand it there is a limited right to  do white box 
reverse engineering in the EEC.  It is a lot more limited than is 
generally assumed in open source circles, and would not extend to 
reproducing internal behaviours.

As I understand it, the key points are:

- it must only be to the minimum degree necessary to interface with the 
- the author of the software must have refused to provide that 
information on reasonable terms;
- the knowledge you gain cannot be published.

Clean room is often used to refer to re-implementing something for which 
the source code is actually available, or for black box reverse 
engineering, where you examine the external behaviour of the software in 
response to external inputs.

Most of the Gnu utilities for Unix are clean room products.

David Woolley
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