[btilly]

I'm very emphatically not picking nits here. See http://www.softwarehistory.org/history/ec.html for an overview of the history. From there you can dive into the early history of the software industry, with names, companies, and more. (They have less detail than I'd like.) For example if you read http://www.softwarehistory.org/history/csc.html you'll find that Computer Sciences Corporation started with $100 and a contract from Honeywell to write a programming language called FACT. They were NEVER in the mainframe hardware sales business. As for consulting, guilty as charged. There was no idea of a market in software, so if your company wanted to get paid for writing software then consulting was your only chance. But that still happens in the software industry.

However despite there not being a recognized market, software that was produced for one client could and did get sold to others. And as the 60s progressed there came to be enough of these pieces of software out there that the first regular catalog of software products for sale got going early in 1967. By the end of the 60s there were hundreds of software packages for sale, and IBM declared that it would get into that business starting January 1, 1970 by unbundling some of its software from its hardware.

By that point there is no question that there was such a thing as a software industry. Small? Yes. But definitely present at a surprisingly early point.