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Notes
This is a rather unique license. It attempts to permit someone to distribute copies of the licensed work (or a derived work) under different terms (including non-free terms where the source is not available) for a period of time not to exceed 12 months. As a result, works under the TGPPL which are using the "Transitive Grace Period" may not be available under Free Software terms, and for the purposes of simplicity, we must assume that any TGPPL licensed works distributed with a "Transitive Grace Period" are non-free, until that "Transitive Grace Period" expires.
However, for works which do not choose to leverage the "Transitive Grace Period", and for which the source code is immediately available for corresponding binaries under the terms of the TGPPL, it is safe to consider those works Free (but GPL incompatible, due to the wording of the license). As the Tahoe-LAFS code is the only known user of the TGPPL at this time, and it does not currently distribute under the "Transitive Grace Period", this distinction is useful.
Any Fedora packages which include TGPPL licensed works must choose not to leverage the Transitive Grace Period.
For the above reasons, Fedora strongly discourages developers from using the TGPPL.
The below copy of the TGPPL 1.0 was taken from https://tahoe-lafs.org/trac/tahoe-lafs/browser/trunk/COPYING.TGPPL.rst on December 2, 2014. It is worth noting that the Tahoe LAFS use of the TGPPL license also includes a number of exceptions intended to resolve license compatibility with other licenses. These exceptions are not part of the TGPPL, and are not included in the below license text.
License Text
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Transitive Grace Period Public Licence ("TGPPL") v. 1.0
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This Transitive Grace Period Public Licence (the "License") applies to any
original work of authorship (the "Original Work") whose owner (the
"Licensor") has placed the following licensing notice adjacent to the
copyright notice for the Original Work:
*Licensed under the Transitive Grace Period Public Licence version 1.0*
1. **Grant of Copyright License.** Licensor grants You a worldwide,
royalty-free, non-exclusive, sublicensable license, for the duration of
the copyright, to do the following:
a. to reproduce the Original Work in copies, either alone or as part of a
collective work;
b. to translate, adapt, alter, transform, modify, or arrange the Original
Work, thereby creating derivative works ("Derivative Works") based upon
the Original Work;
c. to distribute or communicate copies of the Original Work and Derivative
Works to the public, with the proviso that copies of Original Work or
Derivative Works that You distribute or communicate shall be licensed
under this Transitive Grace Period Public Licence no later than 12
months after You distributed or communicated said copies;
d. to perform the Original Work publicly; and
e. to display the Original Work publicly.
2. **Grant of Patent License.** Licensor grants You a worldwide,
royalty-free, non-exclusive, sublicensable license, under patent claims
owned or controlled by the Licensor that are embodied in the Original
Work as furnished by the Licensor, for the duration of the patents, to
make, use, sell, offer for sale, have made, and import the Original Work
and Derivative Works.
3. **Grant of Source Code License.** The term "Source Code" means the
preferred form of the Original Work for making modifications to it and
all available documentation describing how to modify the Original
Work. Licensor agrees to provide a machine-readable copy of the Source
Code of the Original Work along with each copy of the Original Work that
Licensor distributes. Licensor reserves the right to satisfy this
obligation by placing a machine-readable copy of the Source Code in an
information repository reasonably calculated to permit inexpensive and
convenient access by You for as long as Licensor continues to distribute
the Original Work.
4. **Exclusions From License Grant.** Neither the names of Licensor, nor the
names of any contributors to the Original Work, nor any of their
trademarks or service marks, may be used to endorse or promote products
derived from this Original Work without express prior permission of the
Licensor. Except as expressly stated herein, nothing in this License
grants any license to Licensor's trademarks, copyrights, patents, trade
secrets or any other intellectual property. No patent license is granted
to make, use, sell, offer for sale, have made, or import embodiments of
any patent claims other than the licensed claims defined in Section 2. No
license is granted to the trademarks of Licensor even if such marks are
included in the Original Work. Nothing in this License shall be
interpreted to prohibit Licensor from licensing under terms different
from this License any Original Work that Licensor otherwise would have a
right to license.
5. **External Deployment.** The term "External Deployment" means the use,
distribution, or communication of the Original Work or Derivative Works
in any way such that the Original Work or Derivative Works may be used by
anyone other than You, whether those works are distributed or
communicated to those persons or made available as an application
intended for use over a network. As an express condition for the grants
of license hereunder, You must treat any External Deployment by You of
the Original Work or a Derivative Work as a distribution under section
1(c).
6. **Attribution Rights.** You must retain, in the Source Code of any
Derivative Works that You create, all copyright, patent, or trademark
notices from the Source Code of the Original Work, as well as any notices
of licensing and any descriptive text identified therein as an
"Attribution Notice." You must cause the Source Code for any Derivative
Works that You create to carry a prominent Attribution Notice reasonably
calculated to inform recipients that You have modified the Original Work.
7. **Warranty of Provenance and Disclaimer of Warranty.** Licensor warrants
that the copyright in and to the Original Work and the patent rights
granted herein by Licensor are owned by the Licensor or are sublicensed
to You under the terms of this License with the permission of the
contributor(s) of those copyrights and patent rights. Except as expressly
stated in the immediately preceding sentence, the Original Work is
provided under this License on an "AS IS" BASIS and WITHOUT WARRANTY,
either express or implied, including, without limitation, the warranties
of non-infringement, merchantability or fitness for a particular
purpose. THE ENTIRE RISK AS TO THE QUALITY OF THE ORIGINAL WORK IS WITH
YOU. This DISCLAIMER OF WARRANTY constitutes an essential part of this
License. No license to the Original Work is granted by this License
except under this disclaimer.
8. **Limitation of Liability.** Under no circumstances and under no legal
theory, whether in tort (including negligence), contract, or otherwise,
shall the Licensor be liable to anyone for any indirect, special,
incidental, or consequential damages of any character arising as a result
of this License or the use of the Original Work including, without
limitation, damages for loss of goodwill, work stoppage, computer failure
or malfunction, or any and all other commercial damages or losses. This
limitation of liability shall not apply to the extent applicable law
prohibits such limitation.
9. **Acceptance and Termination.** If, at any time, You expressly assented
to this License, that assent indicates your clear and irrevocable
acceptance of this License and all of its terms and conditions. If You
distribute or communicate copies of the Original Work or a Derivative
Work, You must make a reasonable effort under the circumstances to obtain
the express assent of recipients to the terms of this License. This
License conditions your rights to undertake the activities listed in
Section 1, including your right to create Derivative Works based upon the
Original Work, and doing so without honoring these terms and conditions
is prohibited by copyright law and international treaty. Nothing in this
License is intended to affect copyright exceptions and limitations
(including 'fair use' or 'fair dealing'). This License shall terminate
immediately and You may no longer exercise any of the rights granted to
You by this License upon your failure to honor the conditions in Section
1(c).
10. **Termination for Patent Action.** This License shall terminate
automatically and You may no longer exercise any of the rights granted to
You by this License as of the date You commence an action, including a
cross-claim or counterclaim, against Licensor or any licensee alleging
that the Original Work infringes a patent. This termination provision
shall not apply for an action alleging patent infringement by
combinations of the Original Work with other software or hardware.
11. **Jurisdiction, Venue and Governing Law.** Any action or suit relating to
this License may be brought only in the courts of a jurisdiction wherein
the Licensor resides or in which Licensor conducts its primary business,
and under the laws of that jurisdiction excluding its conflict-of-law
provisions. The application of the United Nations Convention on Contracts
for the International Sale of Goods is expressly excluded. Any use of the
Original Work outside the scope of this License or after its termination
shall be subject to the requirements and penalties of copyright or patent
law in the appropriate jurisdiction. This section shall survive the
termination of this License.
12. **Attorneys' Fees.** In any action to enforce the terms of this License
or seeking damages relating thereto, the prevailing party shall be
entitled to recover its costs and expenses, including, without
limitation, reasonable attorneys' fees and costs incurred in connection
with such action, including any appeal of such action. This section shall
survive the termination of this License.
13. **Miscellaneous.** If any provision of this License is held to be
unenforceable, such provision shall be reformed only to the extent
necessary to make it enforceable.
14. **Definition of "You" in This License.** "You" throughout this License,
whether in upper or lower case, means an individual or a legal entity
exercising rights under, and complying with all of the terms of, this
License. For legal entities, "You" includes any entity that controls, is
controlled by, or is under common control with you. For purposes of this
definition, "control" means (i) the power, direct or indirect, to cause
the direction or management of such entity, whether by contract or
otherwise, or (ii) ownership of fifty percent (50%) or more of the
outstanding shares, or (iii) beneficial ownership of such entity.
15. **Right to Use.** You may use the Original Work in all ways not otherwise
restricted or conditioned by this License or by law, and Licensor
promises not to interfere with or be responsible for such uses by You.
16. **Modification of This License.** This License is Copyright © 2007 Zooko
Wilcox-O'Hearn. Permission is granted to copy, distribute, or communicate
this License without modification. Nothing in this License permits You to
modify this License as applied to the Original Work or to Derivative
Works. However, You may modify the text of this License and copy,
distribute or communicate your modified version (the "Modified License")
and apply it to other original works of authorship subject to the
following conditions: (i) You may not indicate in any way that your
Modified License is the "Transitive Grace Period Public Licence" or
"TGPPL" and you may not use those names in the name of your Modified
License; and (ii) You must replace the notice specified in the first
paragraph above with the notice "Licensed under <insert your license name
here>" or with a notice of your own that is not confusingly similar to
the notice in this License.