InfoTech: Open Source may be free but it's not free of restrictions.

Open Source software is not always free of charge: any number of developers have taken the route of saying "we know you will need to modify our software, and we don't mind. So we will release the source code. But you still have to pay for what you get from us, and you still have to meet IP restrictions we set."

That makes complete sense: anyone can buy a book and use an extract from it in a conference paper, for example.

But there is a complication in relation to software for which no price is paid.

There's a general principle in contract law: for a contract to be valid, "consideration" has to be paid.

With free-of-charge software, there is no obvious consideration.

In the case of books, copyright law has come to the rescue: a person who borrows a book pays no consideration for it. But laws protect the rights of the author.

The oft-quoted phrase "code is poetry" underlines this notion: the rights attributable to the author arise not from the contract but from copyright law, although they may be modified by contract.

The issues was thrown in to confusion by a judge in a US case (Jacobson v Katzer and Kamind Associates AKA KAM Industries) who found that a dispute between an open source provider and a user was a matter of contract. The software had been released under a restricted open-source licence called "artistic licence." Persons receiving the code had modified it, and released the modified version as a competing product.

One can see their point: SugarCRM is a leading CRM package. An Indian company called vTiger has modified it, and amalgamated it with a number of other open source packages, and released it under their own brand. Users of any one of more than a dozen common CMS (content management system) packages such as Joomla or Xoops will find that many of the plug-ins, extensions or modules are "ports" of the same item produced for a competing package. A "port" is where system specific coding is re-written to enable the operational part of the product (which is generally independent of the package) to run on an alternative CMS. Or enhancements are written.

In these cases, however, there is a material difference: the modified packages are given away with out charge, often buggy and with an invitation for the "community" to see if others can fix the problems.

The common view of open source is that this is how it works - but in the Jacobson case there is a difference: the licence allowed modification for own use, but not for resale.

On appeal to the Federal Court, Judge Jeffrey White came to the conclusion that seems logical and correct: " "Copyright holders who engage in open source licensing have the right to control the modification and distribution of copyrighted material"

That must be the case. It's the basis upon which Open Source developers have released their code. MySQL's licence contains some very strict terms, despite the code being available. That is how they protected their interest and ended up with a product that was bought by Sun last year. Without those terms, the sale would have been unlikely, perhaps.

But the copyright aspect is just part of the story: when KAM Industries first launched the case in 2006, their pleaded breach of software patents.

There is a 2006 article setting out the position as the Groklaw.net then saw it here (external site)