How to get Attribution information for correct licensing

I would like to use this cutout in the germen Wikipediaprojekt.

:slight_smile: Since the license is CC-BY-SA i need to get the contributors to have a correct licensing. Here i have found a tool to extract the names, but i didn’t find out where to get the ID from.

:frowning: On the other hand anyway it’s not very useful, because if i have to gather the contributors node by node, this will keep me busy a long time.

Isn’t there a more convenient way, lets say like “export”, to get the whole list at a time?

Thanks Dan

There are a load of images from OSM already used by wikipedia.
Just copy what those images do.

You realize that by not mentioning the contributors these images do not fully conform to our CC license, right? I personally do not mind, but in theory some OSM contributor might still take legal action, as no one in the OSM project has the authority to decide about the acceptability of a collective acknowledgement (“by OpenStreetMap contributors”) on behalf of the contributors.

I do not believe anyone will actually object, so the OP can still ignore this like the other Wikipedia authors who uploaded the images mentioned above. Just wanted to mention the legal problems.

I do not know a tool that is able to do that – unfortunately, because it would be required to get a water-proof reusing method.

This is very hard on the server but it works, I just wrote it as a fast hack so sorry for any problems with it:

You will need

  • Perl
  • a Unix or MaOSX terminal
  • wget or curl

Print out all the URLs you need to fetch, if you osm file is named “yourmap.osm”, and out put them to History_Urls.

Using wget to download:

Then count the user contributions

Using curl to download:

Then count the user contributions

First of all, thanks a lot for your answers.

@the_winch: Well these are 187 illegal copies, taking that seriously, these should have bin deleted yet. The problem is, that the uploader takes the responsability! And that will be ME!

@Tordanik: I still do not understand what the sens is, using a CC-BY if the peoples who use your maps do not mention the Authors… (and sometimes not even have the possibility to do so!)

@emj: Thanks a lot (indeed i appreciate it), but i do not have Perl nor a Unix or OSX. I think something like this should be available on your server to create a list of any given map, so the peoples out in the world would not have to pirate copy your maps, don’t you think so?

sincerely Dan

All you need is access to a Mac or Unix machine for five minutes, perl is always installed on Mac and Unix.

  1. find a mac
  2. have your .osm file available
  3. open a Finder window
  4. goto applications
  5. go into Utilities
  6. open terminal
  7. type the things above.

Yeah such a tool would be useful I agree, you just need some ruby Foo to do it, but I’m not sure the DB is optimized for that kind of questions so this method might actually be faster.

Well thanks, for the next time i gonna try it. For this time i have found a free available map as background and patched the most important nodes on it extracting them one by one.

Anyway, thanks to all of you doing that great job, i think you are doing something important!


I don’t agree - I picked a few of these pictures, and they all have the license mentioned in the file attributes.
I guess that is all the license demands for.


@Lulu-Ann: This makes me a little bit confused, i’m not a lawyer, but i have found this: and this: and this:
“When you copy it, you have to give credit to the copyright owner (Attribution).”
And finally this one:

Do i misunderstand something?


Our license is CC-BY-SA, so the requirements are

  • SA: share alike – when you redistribute the work or modifications thereof, you have to use the same license for your version of the work and mention the license.
  • BY: attribution – when you redistribute the work, you have to name the creators of the work.

The images on Wikipedia conform to the SA part, but they do not list the creators, i.e. the OSM contributors who have entered the data. That this may be legally required at least under some jurisdictions is largely consensus on legal-talk – the links DanSy has found and included in his last posting reflect this opinion (and point out some of the other problems with our current license).

To get all users that have edited an area on openstreetmap use:

but from FAQ:**
I know I edited a feature - why is it not listed under my username?
Currently the feature is only listed under the user that last touched it. We are working to make this more flexible.

About the license issue, I would like to state that it should be enough to have “made by Openstreetmap collaborators” as the copyright owner. This is what does so, so this is the way it is done and that weights alot when you are talking about law. If you have a cookie jar where you have to pay, but no one has done this in the last 20 years, then you can’t just pick one random guy have him arrested and still let other people have free cookies.

The need to list all individual contributors seems to me to be contrary to the whole point of OSM - that the maps should be available for use in other projects. Requiring individual contributors to be listed simply means that the vast majority of people will either ignore the licence conditions or simply won’t use the work. The first case is particularly important as if OSM don’t enforce the licence, many courts will simply void it completely.

The fact that it is not possible for one to retrieve a complete list of contributors (see the point above about features only being allocated to the last person who touched them) would seem to make the licence pointless anyway. Even if a complete list of contributors were to be available, should it consist of nickname, full name, address, e-mail address etc.? This opens up a whole new can of worms.

At the moment, it would seem that the easiest way to comply with the licence would be to ‘touch’ every single node within the given area and then only list yourself as a contributor!

Surely ‘BY’ should simply mean stating 'Map from'?


The second statement is clearly wrong, see my first post on this subject, you will gain nothing by touching nodes the history is still there.

The first statement is and old argument against the BSD license which used to have a “give all contributors credit” clausul. But for us handling maps, it would be pretty trivial to add map application to list every contributor to a zoom14 tile, so if the need to do this is great then there will be a solution. Storing contributors names isn’t going to be that much of a deal 10,000 users editting isn’t that much, especially considering the amount of data map applications handle.

I’m not saying it should be done I just say it can be done pretty painlessly (this is acutally easier than getting the map to render)

Edit: just realized that this will be hard to do from a planet.osm dump… :wink:

Well, stating “just use it illegally, trust us, we won’t prosecute you for it” is not the correct way in my opinion.

I don’t know perhaps i’m completely wrong with that, but i think OSM should gather the agreement of the contributors and give out a legal statement saying something like:

“Giving a reference (permalink) of the area used and the citation , is enough to comply with the attribution required by CC.”

Why this:

  1. I think, that there is a of lot work left to do (it’s quite a big world…) and the more peoples are using your maps, the more contributers will have this project, public relation is what it’s all about.

  2. “But i want to be credited for my hard work, i was crawling 2 years through the jungle with my GPS!” Sure the contributors should have the right to be attributed, but who has ever red the creditpage of FireFox or OpenOffice? I didn’t… So, if somebody really is interested in the originator, he also gonna find him/her, if it’s by means of a special page or a link, i don’t see a big difference (except in the case that there is no internet available).

  3. I think it is even better to link the area, because a listing of 10000 nodes is not very useful, nobody will ever read that. If somebody for any reason wants to know, who was the contributor of a specific node, a map is better, because nodes only have numbers.

sincerely Dan

OK. What I should have said was “The fact that it is not possible to easily retrieve a complete list of contributors”.

By way of example, I have the URL “” which I’d like to save as a pretty JPEG.

Even that’s not easy - as soon as I click on ‘export’, my screen geometry changes and I have to dicker about until I can get everything in before I manually crop the image to get back to where I was. Anyway, after all that I have a picture. Now to get the contributors.

Hmmmm. How do I end up with an .osm file? Ah, export as XML doesn’t do what I assumed (create a .xml file), it creates a .osm. Next problem - Now I’ve got to work out what URL to call to get that file down onto the Linux box (no GUI!)…

Hmmm. Here’s where the fun starts. So, I need a way of going from the page URL (for example, “”) to the URL called when the form is submitted (taking into account the change of screen geometry).

OK. I give up, I don’t think I can do that in five minutes. So, I now have the .osm file on the Windows box and I’ll SFTP it to the Linux box for processing…

And so… The end result is:


Which is wrong. “Thomas” should be “Thomas Matern” and “Nick” should be “Nick Barnes”. OK, OK, I know I’m being picky and if I knew Perl I’d hack the code to allow for spaces. However, whether it says ‘Nick’ or ‘Nick Barnes’, that information still isn’t useful in any way, shape or form. Consider a third party looking at the list of names. “Hmmmm.”, they think, “I wonder who ‘blackadder’ is and which part they did”. They still have to come back to the site to find out. This has achieved absolutely nothing more than simply attributing the map to the site would have done in the first place.

Anyway, I ramble. My point is, it is not realistic to expect anybody who wants to use images to be able to do this and I’m also not sure that the usernames are adequate attribution even if it were.

The example above is for a small village and yet has 8 contributors. What about a map of, say, London? Am I expected to list the several hundred contributors? If anybody says ‘yes’ at this point, we may as well all pack up and go home as no bu88er will ever use OSM maps.

Let’s say I want a map of Birmingham on a T-Shirt I’m going to sell. Do you really want me to list all the contributors? Even looking at the ‘press’ section of the wiki and reading the legal licence stuff, it’s not clear that newspapers, magazines et al have to print a complete list. I can’t imagine a journalist would be willing to spend the time collating such a list either.

Attribution by anything other than a single blanket “by OSM contributors” is simply ridiculous. To expect otherwise is ludicrous in the extreme and I suspect that if a licence contravention case ever came to court, OSM would be laughed out of the building. Enforcing the licence in those terms would have the effect of scuttling the ship we’re all sailing in.


Just tried to get the user list for London and couldn’t! I had to zoom in a fair way before the server didn’t choke! 20,000 nodes later, I end up with a list that’s 215 names long.

So, assuming I want a small thumbnail on my website, I’ll need 100 times the space just to list the contributors. Hmmmm.


The accepted standard is a phrase such as:

“Map data licensed CC-BY-SA OpenStreetMap (OpenStreetMap Foundation and contributors)”

hyperlinked to the appropriate places. I’ve copied this verbatim from Andy Allan’s cyclemap and no-one, to the best of my knowledge, has ever objected to that.

CC-BY-SA can be read (indeed, it’s my reading) to say that you have to attribute every single contributor. That is clearly insane. That is one of the reasons why we are actively considering replacing CC-BY-SA with a licence expressly designed for large-scale collaborative databases, i.e. the Open Database Licence.

Of course, in your particular case, “Richard: 6” is me; and like many others, I’ve expressly dedicated all my OSM contributions to the public domain (by means of a little “userbox” on my wiki page). So you can miss out that bit in any case.

@Richard: But i’m not sure, that this is the position of the OpenStreetMap Foundation, because of pages like these:

These are links i have found on this server.

“The accepted standard is a phrase such as…” please tell me, where i can find written something like that on this server.

sincerely Dan

Everything is possible if this is really what you want to have. So the first question is “Should you name everyone that has contributed to this map”, the second is “Can I name everyone who has created this map”.

First question, many people think “Map data licensed CC-BY-SA OpenStreetMap (OpenStreetMap Foundation and contributors)” is enough, even does this, I see nothing illegal with this. I still think contributors should be listed and in most small scale maps this will be possible since many areas only have one contributor (see OSM quality evaluation).

Second question, if you have to you can develop something that does this for you. Your good arguments are about physical media, the t-shirt and that is the kind of things that makes it impossible to name everyone. But information that remains electronically can almost always have attribution, if you have to.

The export function could be explained better, .osm is XML with openstreetmap schema.

I don’t understand how you got the .osm file. I’ve actually thought about this myself, translating map URLs to API URLs is too hard.

Fixed, lazy regexp! I blame it on all Swedes that have sane user names with out spaces. :slight_smile:

I wonder if the fight to enlighten people that intellectual property can be bad, has made people so aware about the cumbersome issues, that they are afraid to create anything at all. CC is about freedom to use our material creatively, and letting other people be creative from that material.