Database License White Paper

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Database license white paper

One of the most important philosophical and social issues confronting humanity in the beginning of the 21st century is the sharing of information. This document examines the issues involved in applying the ideas of Free Software and Open Source to the realm of databases. A database is a highly structured collection of digital information. The focus is on the requirements of a copyleft database license, called GPL Data License (GDL). Readers are assumed to be familiar with topics such as Free software, CopyLeft, GPL, and the difference with Open Source in general.

1. Do we need a new license?

First we define the license problem involving databases. Kernels, compilers, web servers, database servers form the heart of the Free Software world. The use of Free Software ideas outside the source code realm is still somewhat limited. The Free Content License exists now for a while, as well as the GNU Free Documentation license. However these licenses do not properly describe the unique world of databases. Free Software licenses speak of libraries, linking, binaries, etc. where as the database world speaks of record selection, database linking, data-mining and many other terms. We now quote a part of the copyrighted GNU Free Documentation License for explanatory purposes.

The "Cover Texts" are certain short passages of text that are listed, as Front-Cover Texts or Back-Cover Texts, in the notice that says that the Document is released under this License.

Were is the location of the cover text when gazing at a Postgres database table? Other examples of problematic terms are: document, title page, secondary section, and invariant sections.

Because the OpenContent license and GNU Free documentation license also contain terms that do not translate to the database domain, it is impossible to define what constitutes a derived work and re-publication. Those terms are essential to upholding the spirit of copyleft. Database content is much more dynamic when compared to source code and can be republished in various forms on the Internet. Source code behaves much more like a binary functions: you either used GPL code or not. For database content you can copy a few records or all, link to non-free database records with a URL, create scripts that combine content within the browser, etc. We will conclude this paragraph with examples that should indicate the limits of the licenses written outside the database domain. If people think the existing licenses translated OK towards database [ we will gladly hear] for each example below if they are allowed or not.

Some (business) people feel the copyleft idea as to restrictive. We even feel the the GNU Free documentation license is not strong enough to protect the Freedom of users. You probably thought that this was not possible did ya? We feel a strong need for regulating of the right to destroy and to censor information. Both points are lacking in the GNU Free documentation license, we specifically include them.

The examples below might seem far fetched to some people, but they have all already presented themselves in practice. For music information there are two GPL friendly projects, MusicBrainz, FreeDB versus for-profit companies and their databases: CDDB, Allmusic, Muze, Rollingstone, but also projects in the middle such as with almost 45.000 artists. The big question is, to what level is it allowed to combine the information of these projects or is the mixed listing of copyleft and non-free URLs already a violation:-)

  • Is an Open Source MP3 ripping program allowed to lookup an Audio CD at both the non-free database ( with a _very_ restrictive license, the Public Domain licensed database (, and the Copyleft database (
  • Same as above, but now the Copyleft database also has non-factual copyrighted information such as biographies of the artists on the Audio CD?
  • Can I copy two/all/a hundred/a few thousand/N records from a copyleft database and put them on my homepage with links to similar non-free databases?
  • Can I copy a few records from a copyleft database and put them on my copyrighted non-copyleft homepage?
  • May I copy a full copyleft database, run a database server behind my web server and extend it with links to a search script for a non-free database, filled with overlapping information?
  • Can I copy a significant number of (textual) records from a copyleft database and put them on my homepage, and combine each textual record with a link to a picture within a for-profit database?
  • Can I copy a significant number of records of text from a copyleft database and put them on my homepage, and combine each textual record with a non-free copyrighted picture from another database?
  • Is it a copyleft violation to copy a large number of records from a copyleft database and put them on my homepage, together with a JavaScript lookup script that takes information from another for-profit database?
  • Do I violate the copyleft license if I only wrote a program that asks the user for a search keyword, connects to several search web sites, combines the information from both copyleft && non-free databases, and displays the information.
  • Same as above, but not if I wrote such a program, but used it.
  • Same situation, but now the user can select the databases to search, is warned that mixing of free and non-free might violate a license; Does the programmer violate copyleft, does the end-user?
  • Is it a copyleft violation if I extend my for-profit database and web site with a lookup button besides each record that searches related information at a copyleft database?

2. Maximize user benefit

The aim of the GPL Data License is to maximize the benefit toward the general public of the Free Software. The direct benefit is that the user obtains a good product, for which he may not be charged. Only the service of providing means to access that data may come at a cost, the data itself may not be sold. The OPL user must have the freedom to download the entire database at reasonable cost and use it for private purposes as he or she pleases.

The indirect benefit of freedom is that people may choose to increase the size of the database or expand it with other types of information. When the database increase in both size and reach it attracts more developers willing to use this information within application or web sites. With free access user are also more motivated to correct errors and keep the information current. This upward spiral of positivity creates a powerful force. Companies with a competing for-profit database may find it difficult or impossible to follow this upwards spiral, leaving them the option to join or to struggle.

To preserve the freedom you may not modify the content of the database and re-publish the information if you do not give full access. The freedom of the users must be preserved. It is not allowed to take the Free Data, extend it, and charge users money for this extended version.

The user may do anything within the privacy of his own computer with the Free Data. For example, Free Data may be used to check for-profit databases for errors or missing information. Only with re-publication the copyleft kicks in.

The three golden rules of Freedom must be obeyed for a new Free Data license:

  • An unlimited right to copy be granted.
  • An unlimited right to use be granted.
  • An unlimited right to modify for personal use be granted.

3. PD, BSD, LGPL, and GPL

  • There is currently no general license for Free Data. For-profit databases are protected with custom contracts or copyright law. Databases licensed under a Public Domain (PD) license have no restrictions on re-publication or derived works. Companies can take a PD licensed database, extend it and ask money for the content. For a Free Data license such as the LGPL for databases there are restrictions on re-publication of derived works. Asking money for the content is not allowed, a small fee for transportation is OK. Re-publishing derived works from an LGPL database is permitted as long as the whole new database is made available to the public. The LGPL license for software is often used for libraries to increase the popularity with users or usage by companies. Using the LGPL license for Free Data instead of the GPL could be motivated by similar reasons. The GPL database license places further rules on using Open Data. The GPL license has strongest focus on freedom, it requires that the Free Data is not mixed with a for-profit database when re-published.

Some licenses for software have a rule that derived works explicitly carry the name of the creator/author/contributors. For databases we feel that this rule to pay credit is not needed to preserve Freedom and leave it up to, for example, a web page to mention the credits.

Another distinction to make in a license is between commercial users and non-commercial users/companies. We also avoid making this distinction because it conflicts with the copyleft principles.

A translation of the BSD license towards to context of databases would probably be that the BSD license is similar to the PD license, except the original creator keeps the copyright, the database needs to carry the text of the BSD license, and proper acknowledgements must be made. For the remainder of this document we do not consider the BSD license any longer and stick with PD, LGPL, and GPL. The reason for that is the similarity in database context of the PD license and the BSD license.

4. Companies and Free Data

When companies use Free Data it always implies that the data will be used to support their process for generating revenues. This can have both a positive, negative, or neutral impact on the freedom of users. Revenues may be obtained from consultancy work that is required to enhance a web site with Free Data. Companies may get paid to add a non-existing feature to Free Data. Companies with an overlapping for-profit database may use Free Data to detect faulty or missing records.

From the viewpoint of Free Data there are three company types of interest. The first type has a competing non-free database. These companies have the join/struggle option. They may not combine their content with Free Data. The second company type leases/pays companies of the first type for use of their for-profit database. For example, companies selling Audio CDs on a web site like pay companies like $25.000 per year for access to their non-free database containing artist and album info, including album cover pictures. The third company type does not have, or rent a database, but will do so if it comes free of charge with perhaps the copyleft restriction.

An alternative division of companies is to look at their current usage of database and what they might use in the future. This alternative division is important to make when we talk about the implication of using PD, LGPL, or GPL. For example, a company currently pays a large sum every month to access a for-profit database. This company would switch to a PD version if available, but would not use a copyleft database because the spirit of Free Data conflicts with their 'patent loving culture'.

Companies switching types
now\future for-profit PD LGPL GPL
for-profit -/+ + ++
PD -/+ + ++
LGPL -- - ++
GPL -- -- --

The above table lists the different switches a company can make for a certain database. On the side are the four possible data licenses that a company has now, the top row indicates the future data license. The row named 'PD' (Public Domain) has a '-/+' sign in the colom 'for-profit', meaning that a switch type from PD to for-profit is neutral to the Free Data principles. The above devision is in most cases purely theoretical as Free Data is scarce. However for license issues the difference is crucial. The biggest win are companies that switch from for-profit databases towards GPL Free Data.

Software is sometimes released under the LGPL to increase popularity, likewise a database can be released under LGPL or even PD. A reason for not using the GPL is the notion that more companies will use the Free Data if the LGPL is used, or a PD license is used to obtain a maximum amount of industry support at the expense of all copyleft ideas.

Company behaviors names
Class Description
data-freebies Only want to use data if it can be used for direct profit making by asking money for content
data-mixer Only want to use data if it can be mixed with their own for-profit database
data-winners Only want to use data if it follows the rules of the Copyleft community
data-losers Do not care about the license and do not value their Freedom

The first company type, data-freebies, does not want to use the data if it comes with any strings attached. Data-freebies will only use database under the PB license that can be extended and charged money for. This company type does not want to contribute their extensions back to the community. A BSD like requirement of proper credit might even go too far for them. The second type, data-mixers, what to copy and use the database, but want to integrate it with their own database. All modifications they make to the original database, such as inserts or record updates, will be contributed back to the community. However the record in their own private database will not be shared with the community and remains off-limits. The third class are the data-winners, they are fully compliant with the idea of copyleft, they are the RedHat of databases. They will always contribute things back to the community and keep all extensions copyleft. They fully understand the value of copyleft. The final type of company, data-losers, do not appreciate copyleft. They will use the databases which are available to them. They do not have the time or interest to read the license and will just download the data, if available on-line.

When looking for a license of your database you might consider picking the LGPL license to bring in the data-mixer companies. These companies will use your data, but a license for data-winners would give the true spirit of Copyleft. For a database license it might be important to gather more users and companies, but what is the added value of pleasing data-freebie companies? Data-freebie companies will maybe extend your user-base, they will not extend your database. Are the extra users worth the loss of Freedom for your users?

5. Users and Free Data

If Free Data gains momentum with users, it can grow into a powerful force. The copyleft feature of the Free Data would result in a strict division of the Free world and the non-free world. In the long term this could result in a diminished role of non-free databases in areas where users can create and maintain the Free Data themselves. For example, a Free music database with artists and their albums has a large user interest, a Free database of ocean water levels and temperatures will probably not appeal a sufficiently large and active user group to be viable. The size, commitment, and computer skills of a user group are the important properties that determine if a Free database is viable. Another factors have more to do with the properties of the data itself. For example when Free Data is expensive to collect, time consuming to collect, or need frequent updates the user group is strained and Free Data might not be viable. For the context of this license a very important property of the user group is their understanding of the Free Software principles and their appreciation of the freedom that comes with the Free Data.

6. Copyright law

Some database content is protected by law, others is not and may be freely copied and licenses enforcing Copyleft do not apply. The amount of legal protection is determined by the type of content and the country in which the database is located. The European Community provides protection to original and creative database using copyright law. Under European Community directive 96/9/EC protection is also given to databases of numbers and facts. To receive this kind of protection the maker of the non-creative database must show that in the obtaining, verification or presentation of the contents, a substantial investment has been made, be it qualitatively and/or quantitatively.

The European protection is fundamentally different than the US. In the US Supreme Court ruling, Feist Publishing, Inc. v. Rural Telephone Service Co., it was established that mere "sweat of the brow" did not provide collections of information with copyright protection. Some form of "creativity in selection or arrangement" was required. Non-creative databases of facts and numbers cannot be protected under current US law. Until 2001 four bills have been proposed to extend copyright law in the US. A proposed U.S. Congressional bill (H.R. 354) called for even greater protection of database than already present in the Europe. This bill even protects the owner of the database against people that have done an independent discovery of facts in an existing database. Thank God this bill did not make it into law, as the free flow of information would be crippled by it.

7. Derived works and fair use

A very difficult issue is were do we place the border between a derived work and a new work that was only inspired by Free Data.

The crucial idea behind Free Software is that everybody has permission to modify the program and distributed modified versions, but it is _not_ allowed to add restrictions. The Freedom of users must be protected. Likewise, for Free Data it is not allowed to add any restrictions. We interpret the term 'fair use' as meaning usage of data for personal consumption. The copyleft ideas fully promote fair use, as long as no additional restrictions are added.

Defining a derived work for data is different than a derived work for source code because data is more dynamic. Defining a derived work for data is difficult because it has a higher diversity, more formats, and less coherence. For example, source code sits inside .c, .cpp, or .pl files waiting for the editor or compiler. Data resides in many different places such as a simple .txt file, inside a database management system, or on static HTML page. Source code has a human-readably format, defined by the code style. For data there is a wide variety of formats, from unreadable binary to structured XML. All these different formats are equal in a sense. Source code has a high degree of integration, modification in one file affect others. For data it is possible to drop a few tables in the database, add fields with additional information and the consistency is still there. Tables may refer to each other, but the connection is much looser when compared to the coupling that can be found in source code.

For some derived works such as data statistics people might feel that a different license is required. For example, within a music encyclopedia database the average number of albums per artist for every genre (blues, rock, country, ) is not directly listed inside the database, but can be easily derived with some data mining. We feel that the freedom of the user is best served if these 'data mining derived works' would be distributed under the same terms as the Free Data. This mean that they can be used freely as long as they are not mixed with non-free data. The alternative is to create an exception clause for data mining statistics derived from Free Data. Data mining from Free Data would then be licensed under the PD license. This path is a slippery slope because it is difficult to make a distinction between original data and the extracted data mining statistics. It is impossible to make an unambiguous distinction were data modification ends and data mining starts. We feel it is not required to include a data mining copyleft relaxation as the copyleft clause only ensures freedom.

The slippery slope for data mining is also present for derived works for Free Data. Only respecting the Copyleft clause gives you the legal right to use Free Data. Modification to the Free Data must not be kept private when re-publishing. For GPLed source code it would be unthinkable to suggest that using only 3% or 3 functions() of the source code is still OK. The freedom of the Free Data users is also not served by such a clause. For databases the non-free usage of a single field within a table should not be allowed. For GPLed program it is also unthinkable to suggest that only using three functions from a non-free binary only library is still OK. Likewise, using JavaScript to fetch records from both a non-free and Free database, combining them within the browser of the user is a violation of copyleft principles because it constitutes re-publishing a derived work were the result is not Free.

<! In the examples we have seen a few parameters that play a role in the derived work. For example, if the database is copied in full, or that only a limited number of records are copied. Re-publication or not next medium of derived work

  • -database -static HTML -paper printout form -direct fetch of the web site(on-demand-copy) -other?

amount of information copied

  • -a number of records -a number of tables -a mix of records and tables

level of integration

  • level of integration -link to database -link to record -link to script that searches -JavaScript fetches info in other frame

other medium

  • -database -static html -pictures/text/audio


  • -at the browser -at copyleft location -for-profit location

compare free / non-free db

  • -side by side -1 on 1000 -1000 on 1 !>

8. The right to destroy

In the past the regulation of the right to destroy was not an issue and not addressed by Copyleft-type licenses for source code or content in general. Several incidents such as the downfall of numerous .com companies and their databases, loss of tens of thousands of wiki web pages due to technical incompetence have shown that both data and organizations are volatile.

We feel that this volatility in some cases is reason to add a new requirement to protect Freedom, with only a minor inconvenience to people. A large numbers of Free databases will probably be on-line and consist at least partially of user contributed content. The user community that (partly) created this content has protection that this content remains Free due to the already discussed Copyleft requirements. However, it is difficult to backup databases for users when they only have access to the Free data using a web interface. If the both the database and the web site have a complex structure, this is certainly not a trivial task. Thus if organizations go down and backups were not created, then the user contributed Free Data may die with them.

We therefore ask of the people that combine Free user contributions to create at least weekly backups. The most recent backup of the Free Data should be put on-line or send by express mail towards interested people at reasonable cost. The database should be in a common readable database format. This requirement should solve the problem that Free Data can be destroyed at any moment, without much options to users that (partly) created it.

The GNU Free Documentation License has a somewhat similar condition as the one stated above, but this condition is motivated by the need for a standard documentation format. To preserve freedom, derived works must be in a standard format that can be edited by everybody. The GNU license makes a distinction between documents in a transparent format and in a opaque format. A transparent format is an common standard such as Latex, plain ASCII, simple HTML, XML or SGML with a public DTD. An opaque format is a Postscript file, PDF file, proprietary file format such as word.doc, and HTML produced by many HTML editors, and formats that have been deliberately mangled. When creating a derived work of a document released under the GNU Free Documentation License a copy in a transparent format should be made available on-line. Due to several recent incidents we need to extend the GNU Free documentation requirements for the field of Free Data. The HTML web pages also contain the Free Data in a open format, but technically this is not the same as a single tar.gz file that contains each database table in the comma separated value format.

9. The right to censor

A collection of Free Data might contain information on subjects such as drugs, abortion, democracy, bomb making, copyright circumvention, adult content, or Nike/Shell/McDonald's conduct. Such subjects are not always popular and could be removed from derived works to make the Free Data more 'suitable' for use. For example, a large collection of URLs towards the most interesting web sites of the world might get stripped of its more controversial links. Is a copyright license the proper instrument to prevent censorship? It would be great if we could save the day and put an end to censorship, but this requirement may be too complex to describe in the Copyleft license. This is still an open issue.

10. Case studies

Several databases exist on the Internet that use volunteers to submit content and have a restrictive non-free license. Examples include: Internet Movie DB, Ultimate Band List, Compact Disc DB, and even

We will now re-visit the different databases around music. There are two companies with commercial databases, AllMusic and Muze. These companies build their music databases with a large staff of editors. Access to these databases starts from $25,000 per year. Companies like Amazon use these databases for their on-line album sales. The music databases consist of information such as album/artist info, pictures, and sometimes a biography. Besides these two players a company called gracenote also offers a database. The gracenote database is different because it consists of user submissions, its history goes back to 1996.

In 1996 things the Internet Compact Disc DataBase was created. A single central server called "" could be used to access the information of Audio CDs. This server accepted new submissions of Audio CD information. During '98 - '00 the information was growing at 800 Audio CDs/day. But these numbers say nothing about the quality of the submissions. The number of duplicate Audio CDs is high, 5 entries of the same Audio CD under a different number or name is not uncommon. Entries also contain numerous spelling errors. has no mechanism to correct spelling errors. Things changed dramatically when the non-profit server was bought by a company that wanted to make money of the contributions that users had made. The database created by the Internet community could no longer be copied. Patents were obtained and granted. A large public outcry resulted into the start of several projects to create an Open Source competitor for the now commercial

From the five originally started projects, two project are still active. The project was very quick in duplicating the functionality of the commercial server. This project has a very large collection of Audio CDs, more than 440.000 entries. A large group of users query this information at a rate of more than 100.000/day. The server and server do not use a relational database. The servers use a very large collection of files, one for each entered Audio CDs. The second replacement called the MusicBrainz project is far more advanced than CDDB or FreeDB and uses a relational database with over 20 different tables, a working moderation system to correct errors, and audio signature software for recognition of audio track by acoustic properties. The author of this paper is co-founder of this project.

The DMOZ project uses user contributions but does not have an open organization and no Copyleft license for the data. The project is a collection of millions of web links, sorted and organized by web volunteers. The organization is mostly run by big cooperations and commercial interest are high because this database is used by all major Internet providers in the world. The only exception is Yahoo, that has its own competing list or interesting links.

WikiPedia has collected over 190,000 encyclopedia entries. This is one of the few projects that has useful content that is released under the GNU Documentation license. This project does not use a database, but a collection of web pages.

As illustrated by the case studies, there are several projects out there that have non-free data, and a few that have Free Data. We hope that more projects will join the Free world.

Johan. (