[cyphar]

> Software contracts with conditions are license agreements.

That sentence is blatantly false. A contract and a license are different concepts and bound by different laws. That was my point.

In addition, they weren't confused. It looks like you were:

> They set conditions (we will keep it free) just like any software contract where you only get the software if you promise to adhere to some rules.

"keep it free" refers to freedom (as in they will only ever use free software licenses). In fact the FSF also states they will only ever use licenses that are in the same spirit as the GPLvX. It is a contract, because you are assigning your copyright to them -- you have to have an agreement in place in order to do that. Software licensing is a different thing. The FSF actually requires you to give them your copyrights if you want to contribute some code to a project they manage. Many other projects do not do this, so the structure for things like Linux (and some GNU projects) is different and is based on licensing.

[snowwrestler]

Well a license is just a form of contract. In particular, a license is only valid for the term of the licensing contract--once the term expires, so does the license. This permits the licensor to compel the licensee to comply with conditions during the term of the contract. If they don't, the contract is violated and the license is withdrawn.

Copyright assignment is more like a sales contract (at least in the U.S.). It doesn't have a term, but rather is complete once executed. Once it's executed, the new property owner can do what they want with the property. This makes it hard for the seller to compel the buyer to comply with conditions once the sale is done. Like selling a car to someone and saying "if you buy this car you can't drive it to to Texas." Once it's titled in their name, they can drive it wherever they want.

[cyphar]

> Well a license is just a form of contract

Free software licenses (and some proprietary software licenses) are not contracts in any meaningful way. They do not require any of the tests of contract law (meeting of minds, bystander, willingness to be bound, etc) and are implicit agreements (to be fair, contracts can also be implicit but that's not what people are talking about when they say "contracts"). The reason you have to obey the GPL is because the only way you can do anything with the software is by obeying the terms of the license (assuming it's not dual-licensed). That doesn't smell or sound like a contract to me.

> Copyright assignment is more like a sales contract

Except free software copyright assignment gives you non-exclusive rights to licensing anyway (so you only lose the power to sue people, which is not something that software developers do regularly). In addition if you sign a contract to buy a car under the condition that you will drive it to Texas and you don't drive it to Texas, then the contract is voided. Same with houses, or anything else you could possibly sell.