key: cern-ohl-w-2.0
short_name: CERN-OHL-W-2.0
name: CERN Open Hardware Licence Version 2 - Weakly Reciprocal
category: Copyleft Limited
owner: CERN
homepage_url: https://www.ohwr.org/project/cernohl/wikis/Documents/CERN-OHL-version-2
spdx_license_key: CERN-OHL-W-2.0
text_urls:
  - https://ohwr.org/cern_ohl_w_v2.txt
  - https://ohwr.org/project/cernohl/wikis/uploads/10946616b8cbcdef2274a58d9f3a98fb/cern_ohl_w_v2.txt
  - https://ohwr.org/project/cernohl/wikis/uploads/b94a1a92b29984226c56a0dd4dca0d39/cern_ohl_w_v2.pdf
osi_url: https://opensource.org/CERN-OHL-W
faq_url: https://ohwr.org/project/cernohl/wikis/faq
other_urls:
  - https://ohwr.org/project/cernohl
  - https://cern-ohl.web.cern.ch/
  - https://ohwr.org/project/cernohl/wikis/Documents/CERN-OHL-version-2
ignorable_copyrights:
  - copyright CERN 2020
ignorable_holders:
  - CERN
text: |
  CERN Open Hardware Licence Version 2 - Weakly Reciprocal


  Preamble

  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: this licence, CERN- OHL-W (weakly reciprocal)
  and CERN-OHL-S (strongly reciprocal).

  The CERN-OHL-W is copyright CERN 2020. Anyone is welcome to use it, in
  unmodified form only.

  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 Definitions

    1.1 'Licence' means this CERN-OHL-W.

    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 the CERN-OHL-W, or

         c) any licence which permits You to treat the Source to which
            it applies as licensed under CERN-OHL-S or CERN-OHL-W
            provided that on Conveyance of any such Source, or any
            associated Product You treat the Source in question as being
            licensed under CERN-OHL-S or CERN-OHL-W as appropriate.

    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 include Notices.

    1.4 'Covered Source' means Source that is explicitly made available
        under this Licence.

    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 or otherwise.

    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) 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 Product.

    1.8 'External Material' means anything (including Source) which:

        a) is only combined with Covered Source in such a way that it
           interfaces with the Covered Source using a documented
           interface which is described in the Covered Source; and

        b) is not a derivative of or contains Covered Source, or, if it
           is, it is solely to the extent necessary to facilitate such
           interfacing.

    1.9 '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.

   1.10 '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.

   1.11 '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.

   1.12 'Licensee' or 'You' means any person exercising rights under
        this Licence.

   1.13 '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.

   1.14 'Convey' means to communicate to the public or distribute.


  2 Applicability

    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.

    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 or External Material to which it is
            interfaced, which remain licensed under their own applicable
            licences.


  4 Making and Conveying Products

    4.1 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 includes 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.

    4.2 Where You Convey a Product which incorporates External Material,
        the Complete Source for that Product which You are required to
        provide under subsection 4.1 need not include any Source for the
        External Material.

    4.3 You may license Products under terms of Your choice, provided
        that such terms do not restrict or attempt to restrict any
        recipients' rights under this Licence to the Covered Source.


  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 Patents

    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 General

    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 personnel.

    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.

        You may treat Covered Source licensed under CERN-OHL-W as
        licensed under CERN-OHL-S if and only if all Available
        Components referenced in the Covered Source comply with the
        corresponding definition of Available Component for CERN-OHL-S.

    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.
