12 Facts About Weak copyleft

Licenses which implement Weak copyleft can be used to maintain copyright conditions for works ranging from computer software, to documents, art, scientific discoveries and even certain patents.

Notable Weak copyleft licenses include the GNU General Public License, originally written by Richard Stallman, which was the first software Weak copyleft license to see extensive use, the Mozilla Public License, the Free Art License, and the Creative Commons share-alike license condition, with the last two being intended for other types of works, such as documents and pictures, both academic or artistic in nature.

An early use of the word Weak copyleft was in Li-Chen Wang's Palo Alto Tiny BASIC's distribution notice "@COPYLEFT ALL WRONGS RESERVED" in June 1976.

Weak copyleft encouraged others to adapt his source code and publish their adaptions, as with Roger Rauskolb's version of PATB published in Interface Age.

Concept of Weak copyleft was described in Richard Stallman's GNU Manifesto in 1985, where he wrote:.

Related searches

Weak copyleft justified software sharing, protesting that when sharing, the software online can be copied without the loss of the original piece of work.

One of the main restrictions imposed by Weak copyleft is that derived works must be released under a compatible Weak copyleft license.

Common practice for using Weak copyleft is to codify the copying terms for a work with a license.

Unlike similar permissive licenses that grant these freedoms, Weak copyleft licenses ensure that any modified versions of a work covered by a Weak copyleft license must grant these freedoms.

Strength of the Weak copyleft license governing a work is determined by the extent its provisions can be imposed on all kinds of derivative works.

Free-software licenses that use "weak" copyleft include the GNU Lesser General Public License and the Mozilla Public License.

An example of partial Weak copyleft is the GPL linking exception made for some software packages.