Hardware Design Public License Version 0.04
© Graham Seaman 2000 (firstname.lastname@example.org)
[meta]This license contains three parts: the license proper;
comments, explaining the intent of the license proper, and
separated from it by [comment]...[/comment], and meta-comments,
which will be removed from the license once it has been
completed. Meta-comments are separated by [meta]...[/meta].
All comments are in italics.
[comment]This license is intended to achieve similar goals
to those of the GPL (http://www.gnu.org/copyleft/gpl.html)
in the context of hardware designs. It is
not intended to achieve all the different goals those working
on free hardware designs may have, some of which may require
radically different licenses. However, it is intended to cover
hardware designs of all types, including designs for PCBs,
ICs, and Programmable Logic Devices.
Trying to keep it this general
has made the current version sound horribly long-winded. It is more
of an exercise in finding out what the problems are in developing this
kind of license, and what the goals should be, than a practical license,
since there is no organization behind it.
Any version of this license with version number greater than
or equal to 1.0 may be copied and used verbatim. For versions
before 1.0, the license may not be used; however, it may be copied,
and meta-comments may be changed or added at will.
[meta]This license is incomplete, and has never been looked at by
a lawyer. Maybe one day there will be a final valid version 1.0.
In the mean time, you're welcome to use any useful ideas in it
(as I have also borrowed ideas), just not to use the whole thing
under this name. The main sources of the ideas (and parts of the
text) in the license
- Ian Carr de Avelon
- Reinoud Lambert
- And above all, the FSF
- "Manufacturing files" include any files which can be used as
direct input to a process the purpose of which is to permanently change
the electrical or electronic properties of an object.
This includes, but is not limited to, gerber or other files for PCB
manufacture; mask works for IC manufacture.
- "Programming files" include any files which can be used as
direct input to a process the purpose of which is to temporarily change
the electrical or electronic properties of an object.
This includes, but is not limited to, programmable logic device
configuration data for FPGAs or PLDs; executable files for processors.
- The "hardware design" (or simply "the Design") is the set of files associated with this
license by being placed in the same directory as the license,
or subdirectories of the directory containing the license, including
but not limited to manufacturing files and programming files.
Where these files have a textual format, they should contain
a reference to this license (or in the case of software or documentation
any license recognised by the Free
Software Foundation as compatible with licenses issued by
the Free Software Foundation).
[meta]This is the key to the whole license; it avoids the almost
impossible to task of finding a completely general definition
of a hardware design. Note that the legality of covering binary files
with a copyright license is not settled, but that this has become
current practice (eg. Xilinx uses this for FPGA bitstreams)[/meta]
- A "readable" file must be in a format which can be read
by software available to the general public, whether free or for a fee,
with the exception that it must not be encrypted, obfuscated, or have
its readability in any way artifically obstructed.
- "Hardware Design Public License" (abbreviated to "HDPL")
refers to this or later versions of this license.
Terms And Conditions
- The HDPL covers all files included in the hardware design,
except the license itself. You may not impose any further restrictions
on use or distribution of the hardware design than those contained
in the HDPL.
- You may copy and distribute verbatim copies of the hardware
design in any medium. You may charge a fee for the physical act
of transferring a copy via a non-networked medium (such as a CDROM),
and you may offer warranty protection, instructional support, or
other services in exchange for a fee.
You may not charge a fee for the sole purpose of providing access
to the hardware design via a network.
[comment]"Verbatim" implies the inclusion of ALL files making
up the hardware design, including the license file itself.[/comment]
- You may freely modify this hardware design (with the exception of the
HDPL file itself), thus forming a work based on the hardware design, and
copy and distribute such modifications under the terms of section 2 above,
provided that you also meet all these conditions:
- You must cause the modified files to carry prominent
notices stating that you changed the files and the date of
- You must in no way alter any copyright or mask work right
symbols and information contained in the design
- You must cause any work that you distribute or publish,
that in whole or in part contains or is derived from the hardware
design or any part thereof, to be licensed as a whole at no
charge to all third parties under the terms of this license
- You must ensure that all files in the modified design are
readable in the sense defined above.
[comment]Clause 3.3 implies that you may not include in your modification
any work covered by patent or other rights which would invalidate this
[meta]Clause 3.4 is not in the spirit of the gpl. It would be desirable,
but not practical to insist that only free software formats can be used.
As it is, this clause leaves it open to a company to use a proprietary
and secret format only usable by in-house software, and then to offer
that software for sale at a ridiculous price, in order to satisfy the
letter of this clause. This clause may change in future versions.[/meta]
- The requirements of section 3 apply to the modified work as a whole.
If identifiable sections of that work are not derived from the hardware
design, and can reasonably be considered independent and separate works
in themselves, then this license, and its terms, do not apply to those
sections when you distribute them as separate works. But when you distribute
the same sections as part of a whole which is a work based on this hardware
design, the distribution of the whole must be on the terms of this license,
whose permissions for other licensees extend to the entire whole, and
thus to each and every part regardless of who wrote it.
[comment]For example, say the design is a System-On-Chip computer. A person
who adds a UART to this system may distribute the UART design separately
under a different license. But if that person wishes to distribute
the SOC computer design with the inclusion of the UART, the UART design
must fall under the original license[/comment]
- You may copy and distribute the manufacturing and programming
files contained within the hardware design (or a work based on it,
under sections 3,4) separately from the remainder of the hardware
design, provided that you also do one of the following:
- Accompany them with a prominently displayed URL for a
network site available to the general public for a period
of at least 3 years and with no access restrictions from which
the complete hardware design (or the work based on it, as
appropriate) may be downloaded in readable form.
- Accompany them with the information you received as to the
offer to distribute the corresponding complete hardware design
(this alternative is allowed only if you received the manufacturing
and programming files with such an offer, and have not
subsequently modified these files).
[comment]This section has 4 principal purposes:
- To apply similar conditions to those of the gpl to any software
included in the hardware design
- To apply similar conditions to those of the gpl to any programming
information such as fpga bitstreams included in the design
- To prevent users under section 6 from taking the design and
modifying it by adding secret interfaces so that the manufactured
design becomes effectively unusable.
- To enforce the availability of documentation for any manufactured
version of the design, via the following clause.
- You may use manufacturing files contained in the hardware design
for the purpose for which they were intended as defined above (definition
For the purposes of this license, such use is to be considered as a form
of distribution of the manufacturing files, and hence falls under
section 5, with the same requirements.
[meta]The remainder of this license is copied almost word for word from
the GPL. It is likely that extra clauses will have to be added to deal
with potential patent violations and lack of implied warranty[/meta]
- You may not copy, modify, sublicense, or distribute the Design except as expressly provided under this License.
Any attempt otherwise to copy, modify, sublicense or distribute the Design is void, and will automatically terminate
your rights under this License. However, parties who have received copies, or rights, from you under this License will
not have their licenses terminated so long as such parties remain in full compliance.
- You are not required to accept this License, since you have not signed it. However, nothing else grants you
permission to modify or distribute the design or its derivative works. These actions are prohibited by law if you do
not accept this License. Therefore, by modifying or distributing the hardware design (or any work based on the Design), you
indicate your acceptance of this License to do so, and all its terms and conditions for copying, distributing or
modifying the design or works based on it.
- Each time you redistribute the Design (or any work based on the Design), the recipient automatically receives a
license from the original licensor to copy, distribute or modify the Design subject to these terms and conditions. You
may not impose any further restrictions on the recipients' exercise of the rights granted herein. You are not
responsible for enforcing compliance by third parties to this License.
- If, as a consequence of a court judgment or allegation of patent infringement or for any other reason (not limited to
patent issues), conditions are imposed on you (whether by court order, agreement or otherwise) that contradict the
conditions of this License, they do not excuse you from the conditions of this License. If you cannot distribute so as
to satisfy simultaneously your obligations under this License and any other pertinent obligations, then as a
consequence you may not distribute the design at all. For example, if a patent license would not permit royalty-free
redistribution of the design by all those who receive copies directly or indirectly through you, then the only way you
could satisfy both it and this License would be to refrain entirely from distribution of the Design.
If any portion of this section is held invalid or unenforceable under any particular circumstance, the balance of the
section is intended to apply and the section as a whole is intended to apply in other circumstances.
It is not the purpose of this section to induce you to infringe any patents or other property right claims or to contest
validity of any such claims; this section has the sole purpose of protecting the integrity of the free hardware design
distribution system, which is implemented by public license practices. Many people have made generous contributions
to the growing range of hardware designs distributed through that system in reliance on consistent application of that system; it is
up to the author/donor to decide if he or she is willing to distribute a design through any other system and a licensee
cannot impose that choice.
This section is intended to make thoroughly clear what is believed to be a consequence of the rest of this License.
- If the distribution and/or use of the Design is restricted in certain countries either by patents or by copyrighted
interfaces, the original copyright holder who places the Design under this License may add an explicit geographical
distribution limitation excluding those countries, so that distribution is permitted only in or among countries not thus
excluded. In such case, this License incorporates the limitation as if written in the body of this License.
- Each version of the HDPL is given a distinguishing version number. If the Design specifies a version number of this License
which applies to it and "any later version", you have the option of following the terms and conditions either of that
version or of any later version.
- If you wish to incorporate parts of the Design into other free designs whose distribution conditions are
different, you may write to the author to ask for permission.
12th August 2000.