It was illegal to export certain classes of cryptography software. It was however never illegal to export books about that software. So what they did was publis

It was illegal to export certain classes of cryptography software. It was however never illegal to export books about that software. So what they did was publish a hardback book about the algorithm [1], which contained the entire source code of the software. This book was then freely sold all around the world. Now all you had to do was scan and OCR the relevant pages, cat together the resulting files and compile. All perfectly legal. I remember there being distributed proof-reading groups on Usenet and IRC where you would get 1 page of OCR'd text and the corresponding scanned image and you would manually go through and verify and correct the source code. [1] https://books.google.com/books/about/PGP_Source_Code_and_Internals.html?id=xR4ZAQAAIAAJ https://books.google.com/books/about/PGP_Source_Code_and_Int...