A widely held principle in the law is that software is intangible; when you pay for software, you are purchasing a license to use that software. The law generally holds that software is fundamentally different from tangible goods. Of course, we have discussed in an earlier blog post about the physical representation of software. My book The Physics of Computing uses the computation of the mass of a bit as an example (Q = CV; m_bit = m_qQ).
But the line of reasoning of the legal profession has a more fundamental flaw. When I buy a car, no one bothers to consider whether I am purchasing a license to make my own copies of the car. Everyone agrees that I am buying a physical object, no questions asked. In the 20th century, when building a car was a hard, long job, this scenario was a no-brainer. But 3-D printing changes the equation. We can assume that someone will, sooner or later, scan an entire car and 3D print a copy. So where is that fundamental distinction between cars and software?