You found a nice picture or other media file or a whole media collection of a third party that you need very much for an article in one of the Wikimedia projects und thus want to convince them that they should release this stuff under a free license?
So this page tries to be a central collection of good arguments that you can reuse in your (email) requests and at negotiations with the copyright owners. Take the content and adapt it to your needs and please contribute back your best writings here.
Small request 
I'm currently writing an article about [topic] in the free encyclopedia Wikipedia (http://www.wikipedia.org) [replace with your project], which can be found at: [link to article]
During collecting informations about this interesting topic I found your very informative page about this subject.
At the moment the article in Wikipedia contains most of the information I could find so far and I'm searching for some illustrations and pictures for it.
So it would be very nice if I could use some of the illustrations of your page in this article. I'm especially interested in the following ones:
[direct link(s) to picture(s)]
Since Wikipedia is a free encyclopedia, licensed under the GNU FDL (see www.gnu.org/fdl.html), all it content also needs to be under a compatible free license (or in the Public Domain). The main points of this license are:
- (Original) authors (and souces) need to be named
- Everyone can use the content for any purpose, be it commercial or not.
- Everyone is allowed to make changes to the content.
- Modifications of the work need to be made availabe to everyone under the same freedom in a freely available form (for software e.g. the source code; for images a standard image format)
This basically means that it wouldn't be enough allowing me to use these images only for non comercial, educational purpose in this article, since the GFDL explicitly allows reuse, modifications and commercial use.
Since those free image sources are quite rare, I would be happy to use your images.
Many thanks in advance, [your name] - a Wikipedia contributor
requests for lager targets 
Be brief and give a short overview and don't talk to much about details. ;-)
The following text is mainly targeted at scientific institutes and such (but you can for sure take some ideas out of it for other targets as well):
What is Wikipedia? [Replace with your project] 
- Wikipedia is a freely licensed encyclopedia [replace with your projects aim]. It depends on free content that is edited by volunteers from all over the world. Behind Wikipedia is a non-profit organisation called the "Wikimedia Foundation" [link] (placed in Florida/USA), headed by the Wikipedia founder Jimmy Wales.
- Wikipedia is the (already successful) attempt to port the idea of free software (for example the famous Linux operating system) to literature.
- Wikipedia is now in its fifth year and keeps growing exponentially. Independent newspapers have repeatedly stated that Wikipedia is a serious and generally reliable alternative to traditional encyclopedias like Encyclopaedia Britannica or Microsoft Encarta.
What is the GNU Free Documentation License (GFDL)? 
Wikipedia is freely licensed under the GFDL [link] with very similar use conditions as the the popular GPL licensed Linux operating system. Hence we are unable to embed content that is licensed for non-commercial use only as it is with your very high quality images.
What if [company] pictures would be released under GFDL (or equally free)? 
Although we are currently not able to use your images within Wikipedia, we are very interested in doing so, as we have lots of articles about the topic that is covered by your media files, your activities and your projects. At the moment we can use the images of [evil-concurrency-company] as they released their pictures under [Foobar-free-license]. Therefore, images of [evil-concurrency-company] are far more widespread than yours and thus there is no balance in the representation of this topic in Wikipedia. You certainly deserve an even more increased popularity and the key role play the pictures.
So I plead for a free release of your images. You won't lose anything with this step - in contrary, you will get in return a lot for free:
- A visual and educational more attractive representation within Wikipedia (Wikipedia is also used a lot by journalists for quick information retrieval).
- Increased use of your images in the mass media and lots of good PR and more interest from the public.
- A big media echo, as you would be a precursor of the free knowlegde movement. [if the amount of pictures they release is big, pleae only use this point only in such cases of large media databases].
[Your name] - a Wikipedia contributor
In detail arguments for free licenses 
The following tries to cover the most concerns people normally have with free releases of their content
What is the GFDL about? 
Wikipedia is a free encyclopedia, meaning that it content has to be free according the definitions of the GNU Free Documentation license (http://www.gnu.org/licenses/licenses.html#FDL). Note: Free doesn't mean at no cost, but free in the sense of freedom.
The main principles of this license are:
- Credit to the orgininal authors has to be given
- Freedom of usage: Everyone can use the work for every purpose.
- Freedom of modification: Everyone is allowed to modify the work according to his/her own needs.
- Freedom of distribution: Everyone is allowed to distribute the work (original and modified) at the price he/she likes, provided that every interested person gets a transparent (open data format) machine readable copy of the work and that for modifications/derivative work the same rights are given to everyone.
Note: Personal rights (of persons shown in images) and trademark rights are untouched by this license and other free licenses. [very common concern of people you try to convince]
- Dual licensing and CC-BY-[SA].
- more to follow...