YAFFS

Do we need a Licence for YAFFS ?

YAFFS is available free of charge from our web site.

It comes with a GNU Public Licence, GPL: http://www.gnu.org/copyleft/gpl.html which requires users of YAFFS to disclose to any of their customers all the Source Code for YAFFS as well as the compiled Binary files incorporating YAFFS that the customer will use. You can experiment, play, or develop with the free code but you cannot sell the results on, or distribute them free of charge, except under GPL.

What if we link other code to YAFFS ?

That depends on whether it is statically or dynamically linked. Static linking to other code creates a Derived Work, and so, to use the free version of YAFFS under GPL the combined Work must be licensed under GPL also. But the code which YAFFS is linked to may contain its own restrictions on release under GPL; if it does not permit you to distribute the linked code under GPL you will need to buy a suitable Licence for YAFFS from Aleph One. This applies if you use an OS which links statically, for example eCOS, Nucleos, pSos, QNX, ThreadX or VxWorks.
On the other hand if the YAFFS code is Dynamically linked (that is, at Run Time) the combined code is not regarded as a Derived Work and so the parts are each distributed under their own Licences. So long as these Licences allow linking to GPL objects, then you do not need to buy a YAFFS Licence, but if that is not allowed then you will need to buy a Licence. Linux and the BSDs, and WinCE up to version 3, allow such GPL linking.

We do not want to disclose Source Code

You can buy a Licence from Aleph One Limited which, like most software Licences, does not require you to disclose your Source Code. The fee is not less than GB£5000. and may cost well into GB£ Five figures. A Licence is Worldwide, Non-exclusive, Irrevocable and Perpetual, and carries no royalty payment, but the single fee paid when the Licence Agreement is signed. The fee depends on the definition of the Product on which YAFFS will be used and on what use your customers will make of the code, for example if you put it in a SDK for them to develop from.

If you make or design chips and want your customers for the chips to be able to use YAFFS please contact us as we can offer you a suitable general Licence as we have to other firms.

How much does a Licence cost ?

Prices for a proprietary Licence start at GB£5000. and the following factors affect the price:

• Whether it covers both source and binary code for your own use only.
• Whether it covers both source and binary code for distribution to your customers.
• What sort of Product it is for. (We charge more for very high volume products.)
• The Licence is for one Product, and further Products require further Licences, which are usually cheaper than the initial Licence. All Licences are priced in GBPounds, £ and not in US$.

What do we do next ?

Tell us some more about the product you will use YAFFS in, and whether you expect to distribute Source and Binary code or just Binary, and whether you expect you expect your customers to develop their own code from the code you provide to them. If you want us to sign a Non-Disclosure Agree-ment before you give us these details, send it to us; we are used to signing them. We will send a draft Agreement and price to you and negotiate until we are both satisfied. Then we each sign copies of the Agreement and you pay us.

What happens when we sign a Licence ?

When we have signed a Licence Agreement and you have paid us we provide you with files whose headers show that this code is under a proprietary Licence which you have bought from us.

More detail about the definition of a Product is given here and a general discussion of the principles here.