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    Controlled Digital Lending

    Return to Alma Roadmap Highlights Overview


    What is Controlled Digital Lending (CDL)?

    Controlled Digital Lending (CDL) is a developing practice which allows libraries to lend a digital copy of a physical resource in a “lend like print” manner—that is, in the same way in which they lend the physical resource itself. CDL can give libraries and patrons the option of accessing materials in a more flexible manner.

    You can read more about Ex Libris’ vision for Controlled Digital Lending in a recently published white paper: ‘Implementing Controlled Digital Lending (CDL) Responsibly and Effectively: A Primer for Librarians

    Core Principles of CDL

    According to “CDL is the digital equivalent of traditional library lending. A library can digitize a book it owns and lend out a secured digital version to one user at a time, in place of the physical item.”

    CDL has three core principles, according to the Controlled Digital Lending group:

    • A library must own a legal copy of the physical book, either by purchase or gift.

    • The library must maintain an equal “owned to loaned” ratio, simultaneously lending no more copies than it legally owns. (If a library owns three print copies of a book, it could lend no more than two physical and one digital copy at a time, or one physical and two digital copies, and so on.)

    • The library should use technical measures to prevent the digital file from being copied or redistributed.

    Why CDL Matters

    CDL allows libraries to leverage the investment they have already made in existing materials to bring these items to patrons in a more convenient digital format. Here are four key reasons why libraries might want to do so:

    • Digital lending can make items more accessible to patrons

    • Digital formats allow for transformative use of the content - audio / visual aides; full-text searching; zooming in and more

    • Conservation of the originating print copy

    • Reduce environmental impact by avoiding print-book shipments

    Advisory Group

    Ex Libris, together with the community, has formed an advisory group to help guide the development of new features and capabilities within our fully integrated suite of cloud-based solutions to support CDL in an ethical and responsible manner. The goal is to give libraries the flexibility to implement this model in a way that best suits their needs.

    CDL for Course Resources (short-term loans)


    Users of Alma Digital now have features and functionality to support controlled digital lending when managing course resources owned by their institution. The main features are:

    • Limit number of concurrent users according to the number of items on the shelf

    • Limit the loan period to a defined number of hours

    • Enable a patron waitlist for digital resources

    • Allow access and registration to the list via any viewer, and any discovery layer – e.g. Primo, Leganto etc.

    The waitlist management feature helps academic libraries control the circulation of digitized textbooks and other course materials to conform with their institution’s CDL policies.



    Recent Advancements for Course Resources

    List management in Alma

    Provide full transparency and control in Alma over the waitlist. Administrators are able to view the list of patrons, remove from the list and prioritize some users over others.

    Each digital representation editor includes a "Waitlist" tab, including a list of patrons currently waiting for the resources.

    Request list includes:

    • Patron details

    • Place in Queue

    • Actions: Remove, Move to top

    Multiple Policies per CDL resource

    For a single CDL resource, there is a need to exempt specific user groups from CDL restrictions, eg users with print disabilities.

    Alma allows configuring an additional access policy rule in addition to a CDL rule. The following is an example of policy rules which is possible for a single digital resource:

    • Students of the Psychology department can access the resource for 3 hours, 2 students at a time, and register to a waitlist in case the limit has been reached

    • Students with print disabilities can access the resource freely with no no restrictions


    Alma provides statistics on CDL copies of course resources which provide insights on patron usage habits and allow libraries to fine-tune configurations accordingly, or alternatively understand whether additional copies are required.

    Several examples of such statistics include:

    • Average waiting time for a CDL resource

    • Average viewing time of a CDL resource

    • Number of patrons returning a resource early

    • More

    Roadmap plans for Long-term Loans

    Ex Libris is working on designing CDL for long-term loans. This will allow patrons to borrow certain books from the library in a digital format helping libraries serve their patrons and make resources accessible to them within the limits of copyright. The planned enhancements will be leveraging Alma as a unified resource management system, managing the reciprocal relations between physical copies and their digital surrogates. Watch this explainer video for more information.

    Long-term loans will include the following:

    • Maintaining owned-to-loaned ratio of CDL copies for long-term loans, providing parallel management and fulfillment possibilities as print loans

    • Integrate CDL with physical circulation / fulfillment flows, eg suppress physical items once CDL copy is on loan and vice versa; unified list of requests on a title for both physical and digital items and more

    • Configure access rights for digital resources with policy rules specific for CDL

    See CDL plans in the Alma Roadmap Highlights.

    Future enhancements to the Ex Libris suite of products will support CDL within other use cases as well, such as resource sharing between libraries.

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