NUDGING USERS TO
REFERENCE INSTITUTIONSWHEN USING PUBLIC
DOMAIN MATERIALSCreative Commons Guidelines

Ocean Coast by Maurice Denis, Public Domain Mark, Swedish National Museum

INTRODUCTION
The present guidelines offer design ideas and implementation
examples to cultural heritage institutions that wish to encourage
users to reference them in connection with uses of digitized publicdomain cultural heritage materials in their collections. Theguidelines are targeted at institutions that share public domain
content openly and may be of interest to anyone curious about
copyright licensing issues relating to cultural heritage digital objects.

CONTENTS
Introduction

1Background2

Creative Commons Guidelines for Institution Reference

4

What information should be included?

4

How can institutions nudge users?

5

What would a nudge look like in practice?

5

Making it Work: Organizing Data for Design

7

Data Frameworks

7

Schema.org “CreativeWork”

7

IIIF “requiredStatement”

7

Sharing Platforms

8

Europeana

8

Wikimedia Commons8

Additional Support

9

Acknowledgements

9Image Credits

91

BACKGROUNDHURRAY FOR OPEN CULTURE!
Cultural heritage institutions play a fundamental role for the communities
they serve by caring for and sharing the materials in their collections. Theinternet and ensuing digital revolution have spurred a wave of institutions
opening up their collections online, i.e., widely sharing them digitally foraccess, use and reuse free of charge and with no or few copyright
restrictions. As numerous experts explain in our Open Culture Voices
series, openness can lead to countless benefits for local communities andthe general public. The Creative Commons (CC) licenses and publicdomain tools are a crucial part of making “open” happen.

NO CC LICENSES TO RELEASE DIGITAL REPRODUCTIONS OFPUBLIC DOMAIN WORKS
A great deal of cultural heritage elements that have been digitized andmade available online are in the public domain: they are no longer ornever were protected by copyright and may be used by anyone for any
purpose without copyright permission. At CC we are adamant: faithfuldigital reproductions of public domain works must stay in the publicdomain — no new copyright or related right should arise over the digitized
twin. In that vein, CC licenses cannot be used to release digital
reproductions of public domain works, since licenses can only be used inconnection with in-copyright content. To share digitized reproductions ofpublic domain materials, we currently recommend the public domain
dedication tool (CC0).

“PD BY” — A WIDESPREAD BUT PROBLEMATIC PRACTICE
And yet, a great many institutions use CC licenses (not public domaintools) to release faithful reproductions of public domain material. This issometimes amusingly referred to as “PD BY.” Why is this such common
practice? It turns out that many institutions generally wish to beacknowledged for the role they play preserving, restoring, digitizing,sharing, and overall providing context and meaning for the cultural
heritage that they steward. And they use CC licenses (which all require
attribution — the “BY” condition) as a means to require users to reference(or “attribute”) them. CCʼs public domain tools, by contrast, do notmandate attribution. In fact, our Needs Assessment Report: Are theCreative Commons Public Domain Tools Fit-for-Purpose in the Cultural
Heritage Sector? reveals that the main unmet need with CC public domain
tools is for institutions to receive “credit” when material from theircollections is reused and shared — about 53% of institutions that
responded want a way to ensure users “credit” them.

A note on better sharing of public domain materials
We recognize that many collections have found themselves into the stewardship ofinstitutions through complex historical and legal contexts. An objectʼs copyright status is by
no means the only way in which to determine access and use possibilities, let alone
determine rightful ownership or guardianship, as we have stated in relation to open
sharing of Indigenous cultural heritage.

2Sharing Public Domain Collections CC-BY ?!!? by Brigitte Vézina is a remix of “The Scream” byEdvard Munch (1893), Public Domain, National Museum Oslo. Licensed CC BY 4.0

REFERENCING HOST INSTITUTIONS THROUGH CC LICENSES
IS ILL-ADVISED
We generally sympathize with institutions wishing to be referred to whenpublic domain digital objects from their collections are used and for users
to “give credit where credit is due.” However, we strongly advise against
using CC licenses to achieve this in practice for four key reasons:•it creates uncertainty as to the copyright status of the material;•

it is misleading and creates confusion for users as to the access anduse conditions for the material;•

it creates a situation where the licenses are invalid, ineffective, andunenforceable;•

it does not necessarily lead to a mention of the institution, as ourattribution guidelines and the licenses only require mention of thecopyright workʼs title, author or creator, license, and source (typicallya URL).

WHAT ARE INSTITUTIONS TO DO?
In 2022 a CC Open Culture Platform working group led by Deborah De
Angelis (CC Italy) and Tomoaki Watanabe (CC Japan) investigated thisissue in detail and developed proposals for technical, legal, and social
interventions to address the problem of “PD BY.”
Now, inspired by the working groupʼs social intervention, we havedeveloped simple design ideas to show host institutions how they canmake it easy and appealing for people using openly licensed or publicdomain material to reference them. Using the Behavioural Insights Teamʼs
EAST Model — a simple framework to create behavior change or toencourage certain outcomes through “nudges” — we offer a few ways forinstitutions to provide a comprehensive “reference statement,” if andwhere appropriate. These user experience ideas can be used inconjunction with CC licenses and tools. While we do not provide technicalguidelines with HTML/CSS code on how to implement the proposedfeatures, we hope this resource will equip institutions with a design
blueprint that they can implement in their technological environment.
3

CREATIVE COMMONS GUIDELINES FOR
INSTITUTION REFERENCE
WHAT INFORMATION SHOULD BE INCLUDED?
An appropriate statement should include the following information:•••••TitleAuthor or Creator
License or Permissions
InstitutionSource

Here is an example:

Ocean Coast by Maurice Denis, Public Domain Mark, Swedish NationalMuseum
https://collection.nationalmuseum.se/eMP/
eMuseumPlus?service=ExternalInterface&module=collection&objectId=23187
4

HOW CAN INSTITUTIONS NUDGE USERS?
Institutions may nudge or encourage their users to refer to them using theBehavioral Insights Teamʼs EAST model:••••

Easy — Make it easy for people to reference.
Attractive — Make it something they want to do.
Social — Connect the action to social value.
Timely — Provide information at the right moment.

In summary, here are easy and strategic ways institutions may apply theEAST model:
How to make it easy:••

Enable one-click to copy the reference
Auto-highlight the text of the reference

How to make it attractive:•••

Say thank you for using the item
Make the information obvious to users
Provide all the information at the same time

How to make it social:
••
•
•
•

Share number count of downloads
Share number of times reference information is copied
Show an example of an appropriate reference
Invite users to tag the institution on social media
Build trust by showing the source

How to make it timely:••••

Trigger a pop-up when the item is downloaded
Provide the reference with the downloaded fileSend the reference by email
Provide user accounts to keep track of usersʼ own downloads

WHAT WOULD A NUDGE LOOK LIKE IN PRACTICE?
In this section we offer four design ideas of what these strategies mightlook like in practice:••••

A “copy” button
An automatic “pop-up”
A text file download option
A user profile keeping a record of downloads5

Button to easily copy a reference statement

Pop-up displays the reference statement

Download a text file with the material

User profile with a record of downloads

6

MAKING IT WORK: ORGANIZING DATA FOR DESIGNIn this section we offer examples of limited frameworks (all operating
within JSON-LD) and platforms that provide a suitable structure toinclude a reference statement.
What is JSON-LD?
JSON-LD is a lightweight linked data format. Linked data empowers people that publish anduse information on the web. It is a way to create a network of standards-based, machinereadable data across websites. JSON-LD is easy for humans to read and write and is based on
the already successful JSON format. It provides a way to help JSON data interoperate at webscale. JSON-LD is a standard across the platform examples below and is recommended by themajor search engines and makes use of the Internationalized Resource Identifiers (RDIs).

DATA FRAMEWORKS
Schema.org “CreativeWork”
Schema.org is a collaborative, community activity with a mission tocreate, maintain, and promote schemas for structured data on theinternet. The schemas are a set of “types,” each associated with a set ofproperties, which are arranged in a hierarchy. It is the best option forsearch engine discoverability.
The “CreativeWork” type has numerous properties including:
•••
•
•
•

Name (title)
Author and Creator
License and Structure Data License
Publisher
URLCopyright Notice and Credit

These properties make it possible to structure data of a collection in astandard and machine readable way. The input data can be used topopulate another property, e.g., the copyright notice or credit property.
IIIF “requiredStatement”
The International Image Interoperability Framework (IIIF) is a global
standard for collections management and is widely used by cultural
heritage institutions around the world.
IIIFʼs “requiredStatement” is text that must be displayed when an item isdisplayed or used. For example, the “requiredStatement” property canpresent copyright or ownership statements, and reference to the owning
and/or publishing institution, or any other text deemed critical to display
to users.
IIIFʼs “cookbook” for rights statement offers code guidelines andinstructions.
Creative Commons recommends that institutions include in the“requiredStatement” all the information they wish users to reference. This
includes the title, creator or author, the name of the providing institution,
copyright status, license or public domain tool, and the source.

7

A note on ccREL
The Creative Commons Rights Expression Language (ccREL) is the Creative Commons
standard for machine-readable expression of copyright licensing terms and relatedinformation. ccREL is based on the World Wide Web Consortiumʼs Resource Description
Framework (RDF). It was proposed in 2008 and support for the standard has diminishedsignificantly since then. ccREL is no longer recommended for search engine discoverability.
For search engine discovery, we recommend using Schema.org “CreativeWork”.

SHARING PLATFORMS
There are quite a few platforms on which institutions may wish to sharedigital objects from their collection. Here are two of them, which already
implement some of the design ideas presented in these guidelines.
Europeana
Europeana is an aggregator of European cultural heritage collections. It
uses open APIs and other tools to gather information on digitalcollections and provide the world with access and a directory to Europe's
digitized collections.
The platform provides users with a statement when they download anitem. The statement is populated with information from the providing
institution and is part of the minimum required metadata for contributing
to Europeana — it currently includes a reference to the providing
institution. The statement follows the format: [title] by [creator] - [year] [provider], [country] - [rightStatement].
Wikimedia Commons
Wikimedia Commons is the Wikimedia movementʼs collection of media
files, including images, sounds and videos. It provides users with astatement when the uploader has added it to the itemʼs metadata. The
attribution notice can be written in or populated using the metadata
information and include the itemʼs title, creator, publishing institution,and copyright license or public domain tool. This is best included in the“Other fields = {{Credit line}}” section.

8

ADDITIONAL SUPPORTAre you ready to implement one of these designs? Do you have comments on
how to expand or improve these guidelines, especially on the technicalaspects? Would you like to help make this resource available in otherlanguages?
•••Contact us at info@creativecommons.org
Join the Open Culture Platform to engage with peers
Sign up for our volunteer translation process

ACKNOWLEDGEMENTS
These guidelines have been prepared by Connor Benedict, Open Culture
Coordinator, and Brigitte Vézina, Director of Policy and Open Culture, CreativeCommons. It has benefited from useful feedback from members of the Open
Culture Platform working group led by Deborah De Angelis (CC Italy) andTomoaki Watanabe (CC Japan) as well other Creative Commons community
members, and Creative Commons staff, to whom the authors are immenselygrateful.

IMAGE CREDITS•Ocean Coast by Maurice Denis, Public Domain Mark, Swedish NationalMuseum•Sharing Public Domain Collections CC-BY ?!!? by Brigitte Vézina is a remixof “The Scream” by Edvard Munch (1893), Public Domain, NationalMuseum Oslo. Licensed CC BY 4.0•

Download by Andi wiyanto from Noun Project (CC BY 3.0)

•Zoom In by Andi wiyanto from Noun Project (CC BY 3.0)

© Creative Commons 2024 | Creative Commons Attribution License 4.0 (CC BY 4.0)9