Listing or sources you can obtain for a fee are not open source. What DEC and others did is to provide listings you could read, but you weren't allowed to use or modify the code. Sources, maybe, but even then I don't think you could hand the resulting executable bits to anyone outside your organization. On the other hand, there are some interesting cases of code accidentally landing in the public domain, due to having been let out of the building without a copyright notice in place. Until 1976, that would make it public domain. I don't think that happened with any DEC software -- I remember being at the receiving end of some very stern lectures about copyright notices. But it did happen to CDC (in the early mainframe operating system COS) and to IBM (with OS/360). paul On Jan 8, 2013, at 3:08 PM, Clem Cole wrote: You have to understand, the concept of "Open Source" is not new. Most vendors supplied the source listing, and sometime even the code. There was a fee to copy it all (it was said in the old day it was impossible to write a mag tape anywhere for less than $100). So the fees we really set high enough to keep the idiots away, but low enough that the customers that needed them could get them. Remember a lot of it was in assembler, so it did you little good unless you had the vendors HW. A few things changed that all. First, the practice became less prevalent by the later 1970s primarily because of the Amadhl Corp making and selling a 360/370 clone. Interestingly enough, DEC did not sue CalData because of the SW. It was because they cloned the Unibus AND used the PDP-11 instruction set. Second once writing more and more of the OS in a High Level Language became de rigor, the ability to "steal" SW IP seemed to be more of an issue (although DEC was in good shape because no one but DEC would use BLISS). So around the late 1970s, DEC and most other vendors began to be more protective. On Tue, Jan 8, 2013 at 2:56 PM, Dave McGuire <mcguire at neurotica.com> wrote: On 01/08/2013 02:51 PM, Brian Schenkenberger, VAXman- wrote: You need to first sign and pay for a source listings license agreement. Back many years ago, IIRC, it was about $2K. There's then maintenance that must be paid yearly to get the listings CDs/DVDs when produced. I am nothing short of astonished that it was that cheap! -Dave -- Dave McGuire, AK4HZ New Kensington, PA