You can link or use the library in your proprietary code, but any
changes to libbitcoin itself must be released.
libbitcoin can be statically or dynamically linked with proprietary
software.

On 13/05/14 16:33, mlmikael wrote:
> Dear Amir and list,
>
> Originating from the conversation on Bignums, I went through the
> conditions of LibBitcoin's license.
>
> LibBitcoin's present license is the GNU Affero General Public License
> version 3, found at http://www.gnu.org/licenses/agpl-3.0.html . It
> states that
>
> "The GNU Affero General Public License is designed specifically to
> ensure that [...] the modified source code becomes available to the
> community. It requires the operator of a network server to provide the
> source code of the modified version running there to the users of that
> server. Therefore, public use of a modified version, on a publicly
> accessible server, gives the public access to the source code of the
> modified version."
>
> i.e., if you modify it and run a public service with it, you need to
> immediately make your patch clearly and publicly available. From the
> freedom point of view, this is even worse than GNU GPL -
>
> It's not free, in the sense that use in various commercial, academic and
> also community projects frequently is absolutely impossible because
> you're subject to a sharing and disclosure rule incompatible with quite
> standard projects, both embedded/binary distributions *and* in this case
> even running a service with it.
>
> Other Open Source projects like OpenBSD have made similar conclusions
> and kicked out all similar licenses such as all GNU GPL v3+ code, for
> this reason.
>
> For similar reasons, there's projects that provide a dual LGPL and
> Apache or BSD license, or who just go MIT/BSD directly, like BitcoinD.
>
> As a workaround, an Affero library can be used through a "Service as a
> Software Substitute (SaaSS)", subjecting the user to publish only the
> SaaSS/"adapter" sourcecode, however that would probably impose weird
> performance characteristics and therefore painful complexity - so why
> take this route at all if the objective is freedom.
>
> Also, distributing LibBitcoin with binary programs may become a big use
> at some point, and with Affero that is just about impossible.
>
> Publishing a general purpose Open Source library and wanting proper
> attribution for contributions is delivered well by the Apache or LGPL
> licenses, as they requires a public note to be made with the distributed
> application, of the library creator and his copyrights.
>
>
>
> I completely respect all the enormous effort and hard work that has been
> and is going into LibBitcoin, and it really find it to have a huge shine
> to it of being the finest piece of Bitcoin tech around, and I wish to
> open this question:
>
> Is LibBitcoin supposed to be a universal driver of Bitcoin solutions, or
> is it intended to be an open reference implementation but actually used
> in an extremely limited, special subset of projects only, calling for a
> third project apart from both BitcoinD and LibBitcoin to take the role
> of universal driver?
>
>
>
> I hope you find this enquiry humbly expressed. Also, I firmly believe a
> free license would not inhibit LibBitcoin innovation, simply because the
> need for this is so big that there will always be contributors for
> everything that's needed and more.
>
> On the other hand, if LibBitcoin sticks with the Affero license, it is
> probable that it will eventually succumb to a free project, as many
> private and organization users who would be happy to submit patches,
> would prefer a free library day and night for performance, legal, or
> just general principle reasons.
>
> Thanks.
>
>