Useful information about OER

What are OER?

You can’t just take anything you find on the internet and use it in the classroom. Documents, images, and materials are generally protected by copyright, so making copies or using them in presentations is often prohibited. Our work with online platforms and cloud-based services makes us increasingly sensitive to this issue. But some copyright questions are not so easy to answer. “Open Educational Resources” (OER) offer a solution. The authors of OER grant users the explicit right to use their work, issuing the work under a license that makes it clear exactly what is and is not allowed. This means that teachers and students who use OER can be certain they are on legally safe ground.

Making education accessible, enabling collaboration

UNESCO defined open educational resources (OER) in 2012 as “... teaching, learning, and research materials in the form of any medium, digital or otherwise, that reside in the public domain or have been released under an open license that permits no-cost access, use, adaptation, and redistribution by others with no or limited restrictions.”

On the one hand OER therefore improve access to knowledge and education. On the other hand they also offer a special pedagogic potential: Teachers and students can collaborate in adapting the educational media. Not only is this effective, it also fosters creative processes and allows innovative ideas to blossom. In the context of increasingly heterogeneous school classes, it is also an advantage that teachers can adapt existing materials to individual learning and support needs.

The license model of Creative Commons

The non-profit organization Creative Commons (CC) provides seven licensing models that define how materials can be shared, modified, distributed, and remixed. The permissible use of specific content and media are identified in these CC licenses, which have since become a global standard for OER. They give authors the ability to assign incremental rights of use, and they give users transparency about these rights. This way students and teachers can become users and authors in their own right in this same legally unambiguous environment.

The mandate in education is for “as much openness as possible” so that materials can be freely used, modified, and shared. The following three license types serve this aspiration:

  • Public Domain CC 0
  • Attribution CC BY
  • Attribution-ShareAlike CC BY-SA

The other four license types include additional restrictions that, strictly speaking, are no longer “open” and are therefore less appropriate for licensing OER.

Note: The media featured on the Media Portal are (unless otherwise marked) made available under the “CC BY-SA 4.0 international” license.The precise language of this license can be found here:

CC-Licenses at a glance

Public Domain
CC 0

The author waives all rights to his/her materials, which are essentially in the public domain without any restrictions. This means that teachers are free to use the materials in any way they wish.


The author allows the distribution, reproduction, modification, transformation, and even the commercial use of his/her materials – with one restriction: An attribution to the author must be included.


The same conditions apply here as under “Attribution CC BY” with one additional condition: All new works that include the materials in question must be shared under the same licensing terms.


The user may not edit the materials. This contradicts the definition of OER.


The materials may not be used in every context. This contradicts the definition of OER.

Attribution- NonCommercial-ShareAlike

The materials may not be used in every context. This contradicts the definition of OER.


The user may not edit the materials and they may not be used in every context. This contradicts the definition of OER.

Frequently asked questions about OER and CC licenses

The following are the most important questions about OER and CC licenses. These notes about the use of CC licenses have no binding legal effect. Permissible uses of media provided under CC licenses are governed solely by the license terms and conditions, available at, relevant.

1.   How should I attribute a medium (such as a photo) that I want to incorporate into a worksheet, presentation, etc.?

You should always include the identifier of the CC license (in abbreviated form, if applicable), including the version number and the country suffix, if any (e.g., “CC BY-SA 3.0 de” or “CC BY-ND 4.0 international”) together with the license’s URL on the CC license server; for print media this Web address must be written out in full (e.g., “”), but for interactive media like websites or apps it can also be a clickable link.

Additionally, the following information should be included in the notice in the same form as found in the license notice for the work (to the extent that it appears there at all; not all authors or rights holders that use CC licenses provide full information):

  1. (1) The names of all authors or rights holders (= licensors). In the case of the Media Portal, this is the rights holder, such as “© Siemens Stiftung” together with the applicable year.
  2. (2) The name or identification of a person or institution to whom the work was dedicated or entrusted. (This may be, for example, an association on whose website the work was posted online, and that the licensor provides as a reference point for the rights to the work. In the case of the Media Portal, however, this is the same as the name of the rights holder as indicated in (1)).
  3. (3) A link or the Web address where the work was found. In the case of the Media Portal, this is the address of the “Details” of the incorporated medium. The data to be included can be found in the “License” field by clicking on “How to reference the medium.”
  4. (4) A link or the Web address where additional notices about rights to the work or liability exclusions can be found. This is rather rare for individual CC-licensed works, but is standard for repositories like Wikimedia Commons, where each object has such a “rights page.” In the case of the Media Portal, no notice is required.
  5. (5) In the case of adaptations, an indication of what the adaptation consists of, such as “Translated from English,” “Photo cropped from original,” etc. Not all types of CC licenses permit adaptations, but the CC BY-SA 4.0 license used for the Media Portal does.
The CC BY-SA 4.0 license used for the Media Portal also does not require that the title of the incorporated medium – called the “object name” on the Media Portal – must be stated. Nevertheless, it should be included whenever possible. For CC licenses with version numbers of 3.0 or below, which are still frequently used elsewhere, mentioning the title of the used work is mandatory; in case of doubt, this means the file name if the work, such as a photo, is untitled.

2.   What attribution should I use if I want to incorporate multiple media (photos, graphics) in my teaching material?

Here again, the attribution (as explained above) should be provided for each individual medium, so far as possible. However, if there are multiple media, it is sometimes preferable to collect the attributions in a single place: for incorporated photos, for example, in a “Photo Credits” list, or in the opening or closing credits for a video. The CC license permits anything that is standard practice for books, films, pieces of music, etc.

For multiple media that are covered by the same credit (for example, multiple segments of text taken from the same medium), the attribution can also be simplified by indicating something like “Sections F.1, F.5 and F.6 taken from ...,” or also “Unless indicated otherwise, texts are from ...,” in each case followed by the usual attribution.

3.   Must I always apply the name immediately beside the medium, or is it enough if I list sources at the end or in the footer of my teaching materials?

Attribution separately from the work is also permissible under CC licenses (see Question 2). The rule is: as close to the work as possible without disrupting the impression of the overall presentation too severely. So it’s not an absolute requirement to place the attribution immediately next to the incorporated work if the attribution would attract a disproportionately large amount of attention to itself. An abstract minimum requirement for attributions is that an observer interested in the origin of the inserted work must be able to find the information about its rights and source without any great effort.

4.   Must I always include the license button (the logo, for example of “CC BY-SA”) next to the mention of the name?

No. But the exact type of license must nevertheless be recognizable. If the license button is not incorporated, the identification of the license must be visible in legible form elsewhere. The license buttons serve mainly to increase the recognition effect, which represents a major strength of standardized licenses, precisely like that of Creative Commons. To that extent it makes very good sense to use the buttons.

5.   How must I indicate the CC license?

By both naming the exact designation (license type + version number + country suffix, if any, and here the abbreviated form is considered sufficient), and also by making direct reference to the Creative Commons server (in the form of a link or written-out Web address, e.g., This ensures that the correct license text is always referenced. See also the first question above and the examples in question 16.

The only permissible alternative to a reference is to print out the license in full, for example as an appendix to a book. But since the license texts are relatively long, the reference variant is almost always chosen.

6.   Where must the CC license notice appear?

So far as possible, right where the incorporated medium is seen, meaning on the same page of the worksheet or the same slide in the presentation. However, the license notice can generally appear anywhere an observer would expect it, such as at the beginning or end of a presentation, in the production credits of the worksheet, or somewhere else. The wording of the “attribution” term of the license is quite flexible, and requires a mention in “any reasonable manner based on the medium.” If a license notice immediately next to the incorporated medium is impossible or seems out of proportion, for example because the text of the license notice is so long that it would adversely affect the layout, this means the identification may also be moved to a separate list of “Photo Credits” or the like; see above as well.

7.   Whom should I name as “BY” for Siemens Stiftung media: the author or the rights holder?

For media from the Media Portal, the name given in the “rights holder” field should appear (see “Details”), such as “© Siemens Stiftung”.

8.   Where can I find the information for “BY”?

On the Media Portal you can find this information under the “Details” on each medium in the “rights holder” line.
For other portals and websites where CC licensed works are available, you may have to go through the information provided there until you find the indications about who is the author or holds the rights. The author(s) or rights holder(s) are relatively free to decide where that is done. The production credits at the end are often used for this purpose, or the “about us” pages.

9.   How much text can I use before I must indicate that I’ve drawn the text from a Siemens Stiftung medium and incorporated it into my own teaching materials? How and where should I indicate that?

The specific rules for this may vary from one country to another. In general, whatever can no longer be considered a quotation under your country’s laws (or is not explicitly allowed by other exceptions) must be highlighted with a reference to the Siemens Stiftung and the CC license. Even in those cases where use is permitted by exceptions in a country’s laws, a source indication is often still necessary.

For example, German copyright law provides for a right of citation, so that one can incorporate even rather large sections of others’ texts, photos, etc., at full scale, without permission, provided
a) that it serves explicitly to examine the content of the other’s work (as a rule, with words),
b) that it takes only as much as is necessary for the purposes of this examination, and
c) that the source is indicated.

The rules that apply always depend on the country where the user intends to use the text. In other words, a user from Chile must find out how much text can be used under Chilean law, and subject to what conditions. But since the CC licenses do make it possible to incorporate text if Siemens Stiftung and the license are mentioned, in case of doubt you can always include a notice of author and license.

10. What is the extent of changes beyond which I must state that I’ve changed something in the medium? How should I state this?

It depends on the laws of the country where the user makes the changes. In Germany, for example, all changes that are made in the work itself or its immediate environment and that can be perceived by the observer are legally relevant. That is very clearly the case when photos are cropped or their size is greatly changed, but also when videos are set to music, texts are revised, music is abridged, and similar interventions take place. Not until the changes are so massive that the initial work no longer “shines through the cracks” does an independent new work result that can be used without regard to any permissions. Naturally we cannot give the rules here for every country. So users should find out about the legal situation in their home country. Where this information can be found varies – it may be available from the Ministry of Justice or some other authority. Wikipedia can serve as a good entry point in many countries.

A change is not legally relevant if multiple works are merely presented together in a loose association, for example in a worksheet composed of texts and pictures. Additionally, the CC licenses explicitly point out that changes in the file format are not considered legally relevant changes.

As to how the change must be identified, CC licenses provide little in the way of requirements, so that it is sufficient to briefly identify the nature of the change. Examples: “A translation from English of [the work]” or “An excerpt from the photo…,” in each case followed by the general attribution.

11. How many previous adapters must I mention if I adapt the work myself?

Generally, all of them, even if that results in longer and longer license notices if there are multiple stages of adaptation. Legally, there has simply been no clarification as yet of whether and at what point a mass of adaptations and adapters can become so muddled that legally they no longer count individually as collective authors. But in practice, really large groups of several hundred adapters occur only in large community projects like Wikipedia, which resorts to special Wiki pages on the history of a given article to cite attributions. In most cases, even with multiple adaptations of a work, there will seldom be more than a few dozen authors, who in case of doubt must then all be included in the CC license notice. Only if an author’s individual contribution is entirely eliminated – for example, because the passage he authored has been entirely rewritten – can he also be omitted from mention as an adapter or collective author. In practice, however, this can hardly ever be really accomplished except by way of technical solutions, as on Wikipedia.

For media obtained directly from the Media Portal, the situation is simpler in that only the indication of the “rights holder” must be taken over from there, no matter how many individuals collaborated on the medium concerned.

12. Can I combine media that are covered by different CC licenses?

Conditionally, yes. First the combination must really link the content so closely together that an average observer would no longer see them clearly as separate works. Otherwise the question doesn’t arise, because if different works are merely presented next to one another and not merged together, in legal terms there is only a “composite work,” and the difference in the licenses is of no concern.

But if the combination results in a unified new impression, it depends on the terms of the different licenses whether the result can be used without further permission from the authors or rights holders concerned.

Since Siemens Stiftung content is under a BY-SA license, it can be combined only with materials that are likewise under a BY-SA license (Version 2.0 or more recent).

The Creative Commons Wiki has a matrix showing combinability of materials under various CC licenses at:

13. Must I always provide a direct link to the CC license text page?

As a licensee, yes. However, licensors are free to decide when they release a work whether they will place a link on the license, write out the associated Web address of the license, or merely use the abbreviated or full-length name of the license. The latter is done very often, so that later users must find out the link themselves in order to provide notices in compliance with the license. For the sake of transparency and ease of use by the user, licensors may also find it advisable to provide the direct license link with the license button.

On the Media Portal, the direct license link is associated with the license button.

14. What am I not allowed to do with CC-licensed media?

Any kind of use that is not permitted by the Copyright Act (such as the right of citation, see above) or by the license is still reserved for the author or rights holder. So you must ask for permission in advance. But for CC licenses, it is clear from the license name itself what (few) uses are not permitted:

For licenses with “NC” in the name you must inquire if you plan to use the work commercially. For those with “ND” you must ask if you have plans to adapt it. For those with “SA” in the name you cannot impose different license terms for an adaptation without the permission of the author or rights holder for the original work. For the rest, all CC licenses include permission for every conceivable use that is relevant to copyright. This includes duplication, dissemination, posting on the Internet, transmission, performance, exhibition, etc.

But in addition to copyright, the different rules for what are known as authors’ personality rights must be complied with. This means that an author can also take action if his or her work covered by a CC license is disfigured. However, anyone who places a work under a CC license cannot use personality rights to exclude uses permitted under CC licenses. That would be the case, for example, if a licensor, after a CC release of a video, claims author’s personality rights to make every use specifically for television subject to an individual permission (under personality rights rather than copyright). For that reason, the license clearly states that the licensor cannot assert personality rights in contradiction to the CC license.

The user of a CC licensed work also cannot arouse the impression that the user is specially permitted to use the work with particular support from the licensor, since in reality, under the CC license, anyone may use the work who complies with the license terms. This “no endorsement rule” is intended to ensure that licensors cannot be coopted unasked for purposes that lie behind uses by third parties whom the licensors do not even know.

Finally, the rights of persons portrayed or recorded must be respected, even with a CC license, and not only by the users of the CC licensed photographs or recordings, but by the licensors themselves at the time of release. Both the licensors and users of CC licensed pictures should therefore always pay attention to whether all persons portrayed have consented, or whether there are exceptions for press reporting or the like. In the case of the Media Portal, consents from portrayed persons have been obtained – so far as required by law – so that there is no need to inquire further.

15. If I nevertheless infringe a copyright unintentionally, what can happen to me?

Not everyone whose copyright has been infringed insists on the consequences. The Siemens Stiftung and its authors likewise do not set a priority on litigating for unintentional license breaches or other copyright infringements. But fundamentally, in such a case there is the possibility of civil claims for injunctions, damages and reimbursement of expenses, for example for the cost of serving a warning notice. As a rule there is no threat of criminal consequences for unintentional infringements.

16. How do I identify a file from the Media Portal that I wish to use in my own materials?

The following example shows the correct attribution of a photograph from the Media Portal in online publications that work with clickable links:

“The hand bones (JPG)”, Siemens Stiftung 2015, shared under CC BY-SA 4.0

... where the parts highlighted in color contain links to the following destinations ...

  • “The hand bones (JPG)” -> Internet address of photo on Media Portal – in our example
  • CC BY-SA 4.0 -> Internet address of the license – in our example

If materials are drawn from sources outside the Media Portal of the Siemens Stiftung, it is important to note whether those materials use a version of the license adapted specifically for a given country; this should be identifiable in the form of a country abbreviation like “de” for Germany.

However, the links mentioned here – except for the link to the license, which must always be known and discoverable – are necessary only if you know the Internet addresses in the first place, because they were found when you searched the photo (the Web address of the photo) and/or because the Licensor specified them

The following example shows the attribution of the same picture in print publications, or in cases where clickable links cannot be used online.

“The hand bones (JPG)” (, © Siemens Stiftung 2015, licensed under CC BY- SA 4.0 (for text of license see”

Note: Under “Details” for each medium, in the “License” field you will find the note “How to reference the medium.” If you click on this, the corresponding HTML code or text will appear and you can copy it from there.

Authors: John H. Weitzmann, Matthias Spielkamp,

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