A common
method of
duplicating a product is called "
clean room reverse engineering". This involves having two separate teams of
engineers. The important thing is that these two teams never see each other, talk to each other, pass each other in the hallway, or have any
contact whatsoever. Team A (or the
dirty team) is sent to
reverse engineer the
original product (also called the
target product). They
take it apart, run tests on the
components and the whole, and generally figure out
what makes it tick. They then draw up their conclusion, as a set of complete
specifications for the product, in a
document called a
Design Document. Their job is over; they are then dismissed. The design document is handed over to Team B (or the
clean team). Using this document, they then
reconstruct the product from scratch to do exactly the same thing that the original did.
This process is used to
sidestep legal issues with reverse engineering a product with the intent of duplicating it. The dirty team has no intent of duplicating it and the clean team has never
reverse engineered the product. It is important, for legal purposes, that the clean team has never seen or used the original product at all.
A well-known case of clean room reverse engineering involves the
IBM PC. In
1982, the
IBM PC was a widely-used
computer. While various attempts to copy it had been made, these attempts all resulted in an
imperfect copy that was similar, but not
identical to the PC, and were unfit for many purposes. An engineer named
Rod Canion decided to make money off the situation by forming a company called
Compaq, which used the
clean room procedure to clone the IBM
ROM BIOS (the most important piece of the PC that was
proprietary to IBM) and create the
Compaq Portable PC.
Being not only 100%
compatible with the IBM PC, but also cheaper, not to mention portable, made the Compaq very popular and sparked the whole
PC clone industry.