CERN Open Hardware Licence Version 2 - Strongly Reciprocal
CERN has developed this licence to promote collaboration among hardware designers
and to provide a legal tool which supports the freedom to use, study, modify,
share and distribute hardware designs and products based on those designs.
Version 2 of the CERN Open Hardware Licence comes in three variants: CERN-OHL-P
(permissive); and two reciprocal licences: CERN-OHL-W (weakly reciprocal)
and this licence, CERN-OHL-S (strongly reciprocal).
The CERN-OHL-S is copyright CERN 2020. Anyone is welcome to use it, in unmodified
Use of this Licence does not imply any endorsement by CERN of any Licensor
or their designs nor does it imply any involvement by CERN in their development.
1.1 'Licence' means this CERN-OHL-S.
1.2 'Compatible Licence' means
a) any earlier version of the CERN Open Hardware licence, or
b) any version of the CERN-OHL-S, or
c) any licence which permits You to treat the Source to which it applies as
licensed under CERN-OHL-S provided that on Conveyance of any such Source,
or any associated Product You treat the Source in question as being licensed
1.3 'Source' means information such as design materials or digital code which
can be applied to Make or test a Product or to prepare a Product for use,
Conveyance or sale, regardless of its medium or how it is expressed. It may
1.4 'Covered Source' means Source that is explicitly made available under
1.5 'Product' means any device, component, work or physical object, whether
in finished or intermediate form, arising from the use, application or processing
of Covered Source.
1.6 'Make' means to create or configure something, whether by manufacture,
assembly, compiling, loading or applying Covered Source or another Product
1.7 'Available Component' means any part, sub-assembly, library or code which:
a) is licensed to You as Complete Source under a Compatible Licence; or
b) is available, at the time a Product or the Source containing it is first
Conveyed, to You and any other prospective licensees
i) as a physical part with sufficient rights and information (including any
configuration and programming files and information about its characteristics
and interfaces) to enable it either to be Made itself, or to be sourced and
used to Make the Product; or
ii) as part of the normal distribution of a tool used to design or Make the
1.8 'Complete Source' means the set of all Source necessary to Make a Product,
in the preferred form for making modifications, including necessary installation
and interfacing information both for the Product, and for any included Available
Components. If the format is proprietary, it must also be made available in
a format (if the proprietary tool can create it) which is viewable with a
tool available to potential licensees and licensed under a licence approved
by the Free Software Foundation or the Open Source Initiative. Complete Source
need not include the Source of any Available Component, provided that You
include in the Complete Source sufficient information to enable a recipient
to Make or source and use the Available Component to Make the Product.
1.9 'Source Location' means a location where a Licensor has placed Covered
Source, and which that Licensor reasonably believes will remain easily accessible
for at least three years for anyone to obtain a digital copy.
1.10 'Notice' means copyright, acknowledgement and trademark notices, Source
Location references, modification notices (subsection 3.3(b)) and all notices
that refer to this Licence and to the disclaimer of warranties that are included
in the Covered Source.
1.11 'Licensee' or 'You' means any person exercising rights under this Licence.
1.12 'Licensor' means a natural or legal person who creates or modifies Covered
Source. A person may be a Licensee and a Licensor at the same time.
1.13 'Convey' means to communicate to the public or distribute.
2.1 This Licence governs the use, copying, modification, Conveying of Covered
Source and Products, and the Making of Products. By exercising any right granted
under this Licence, You irrevocably accept these terms and conditions.
2.2 This Licence is granted by the Licensor directly to You, and shall apply
worldwide and without limitation in time.
2.3 You shall not attempt to restrict by contract or otherwise the rights
granted under this Licence to other Licensees.
2.4 This Licence is not intended to restrict fair use, fair dealing, or any
other similar right.
3 Copying, modifying and Conveying Covered Source
3.1 You may copy and Convey verbatim copies of Covered Source, in any medium,
provided You retain all Notices.
3.2 You may modify Covered Source, other than Notices, provided that You irrevocably
undertake to make that modified Covered Source available from a Source Location
should You Convey a Product in circumstances where the recipient does not
otherwise receive a copy of the modified Covered Source. In each case subsection
3.3 shall apply.
You may only delete Notices if they are no longer applicable to the corresponding
Covered Source as modified by You and You may add additional Notices applicable
to Your modifications. Including Covered Source in a larger work is modifying
the Covered Source, and the larger work becomes modified Covered Source.
3.3 You may Convey modified Covered Source (with the effect that You shall
also become a Licensor) provided that You:
a) retain Notices as required in subsection 3.2;
b) add a Notice to the modified Covered Source stating that You have modified
it, with the date and brief description of how You have modified it;
c) add a Source Location Notice for the modified Covered Source if You Convey
in circumstances where the recipient does not otherwise receive a copy of
the modified Covered Source; and
d) license the modified Covered Source under the terms and conditions of this
Licence (or, as set out in subsection 8.3, a later version, if permitted by
the licence of the original Covered Source). Such modified Covered Source
must be licensed as a whole, but excluding Available Components contained
in it, which remain licensed under their own applicable licences.
4 Making and Conveying Products
You may Make Products, and/or Convey them, provided that You either provide
each recipient with a copy of the Complete Source or ensure that each recipient
is notified of the Source Location of the Complete Source. That Complete Source
is Covered Source, and You must accordingly satisfy Your obligations set out
in subsection 3.3. If specified in a Notice, the Product must visibly and
securely display the Source Location on it or its packaging or documentation
in the manner specified in that Notice.
5 Research and Development
You may Convey Covered Source, modified Covered Source or Products to a legal
entity carrying out development, testing or quality assurance work on Your
behalf provided that the work is performed on terms which prevent the entity
from both using the Source or Products for its own internal purposes and Conveying
the Source or Products or any modifications to them to any person other than
You. Any modifications made by the entity shall be deemed to be made by You
pursuant to subsection 3.2.
6 DISCLAIMER AND LIABILITY
6.1 DISCLAIMER OF WARRANTY -- The Covered Source and any Products are provided
'as is' and any express or implied warranties, including, but not limited
to, implied warranties of merchantability, of satisfactory quality, non-infringement
of third party rights, and fitness for a particular purpose or use are disclaimed
in respect of any Source or Product to the maximum extent permitted by law.
The Licensor makes no representation that any Source or Product does not or
will not infringe any patent, copyright, trade secret or other proprietary
right. The entire risk as to the use, quality, and performance of any Source
or Product shall be with You and not the Licensor. This disclaimer of warranty
is an essential part of this Licence and a condition for the grant of any
rights granted under this Licence.
6.2 EXCLUSION AND LIMITATION OF LIABILITY -- The Licensor shall, to the maximum
extent permitted by law, have no liability for direct, indirect, special,
incidental, consequential, exemplary, punitive or other damages of any character
including, without limitation, procurement of substitute goods or services,
loss of use, data or profits, or business interruption, however caused and
on any theory of contract, warranty, tort (including negligence), product
liability or otherwise, arising in any way in relation to the Covered Source,
modified Covered Source and/or the Making or Conveyance of a Product, even
if advised of the possibility of such damages, and You shall hold the Licensor(s)
free and harmless from any liability, costs, damages, fees and expenses, including
claims by third parties, in relation to such use.
7.1 Subject to the terms and conditions of this Licence, each Licensor hereby
grants to You a perpetual, worldwide, non-exclusive, no-charge, royalty-free,
irrevocable (except as stated in subsections 7.2 and 8.4) patent license to
Make, have Made, use, offer to sell, sell, import, and otherwise transfer
the Covered Source and Products, where such licence applies only to those
patent claims licensable by such Licensor that are necessarily infringed by
exercising rights under the Covered Source as Conveyed by that Licensor.
7.2 If You institute patent litigation against any entity (including a cross-claim
or counterclaim in a lawsuit) alleging that the Covered Source or a Product
constitutes direct or contributory patent infringement, or You seek any declaration
that a patent licensed to You under this Licence is invalid or unenforceable
then any rights granted to You under this Licence shall terminate as of the
date such process is initiated.
8.1 If any provisions of this Licence are or subsequently become invalid or
unenforceable for any reason, the remaining provisions shall remain effective.
8.2 You shall not use any of the name (including acronyms and abbreviations),
image, or logo by which the Licensor or CERN is known, except where needed
to comply with section 3, or where the use is otherwise allowed by law. Any
such permitted use shall be factual and shall not be made so as to suggest
any kind of endorsement or implication of involvement by the Licensor or its
8.3 CERN may publish updated versions and variants of this Licence which it
considers to be in the spirit of this version, but may differ in detail to
address new problems or concerns. New versions will be published with a unique
version number and a variant identifier specifying the variant. If the Licensor
has specified that a given variant applies to the Covered Source without specifying
a version, You may treat that Covered Source as being released under any version
of the CERN-OHL with that variant. If no variant is specified, the Covered
Source shall be treated as being released under CERN-OHL-S. The Licensor may
also specify that the Covered Source is subject to a specific version of the
CERN-OHL or any later version in which case You may apply this or any later
version of CERN-OHL with the same variant identifier published by CERN.
8.4 This Licence shall terminate with immediate effect if You fail to comply
with any of its terms and conditions.
8.5 However, if You cease all breaches of this Licence, then Your Licence
from any Licensor is reinstated unless such Licensor has terminated this Licence
by giving You, while You remain in breach, a notice specifying the breach
and requiring You to cure it within 30 days, and You have failed to come into
compliance in all material respects by the end of the 30 day period. Should
You repeat the breach after receipt of a cure notice and subsequent reinstatement,
this Licence will terminate immediately and permanently. Section 6 shall continue
to apply after any termination.
8.6 This Licence shall not be enforceable except by a Licensor acting as such,
and third party beneficiary rights are specifically excluded.