Is CDISC Making a Big Mistake?

Update: Please see reply from Chris Decker to this article, where he clarifies that CDISC CORE and executable rules will remain open-source, which resolves big part of concerns raised in this article.

CDISC recently announced its intentions to implement a persistent freemium model. Freemium is a combination of the words "free" and "premium". It is a common and efficient model in which a base product is offered for free, and users pay for additional premium-tier features. In general, there is nothing inherently bad about it, it is an accepted business model, and most likely, you use freemium products in your daily life, such as YouTube, Spotify, Duolingo, Slack, Zoom, and many more.

Last week's announcement of the 2026 CDISC membership rates and benefits (https://www.cdisc.org/membership/rates-benefits/2026) contained a critical, yet not explicitly stated, policy shift. This change removes access to the CDISC Library, Standards Browser, and digital formats for non-members, providing them with PDFs only. And most crucially, the CDISC CORE engine and executable CDISC Open Rules used by the engine will no longer be available for non-members. 

It is logical to assume the goal is to attract new members and retain existing ones, leveraging the same strategy used by commercial companies: widening the gap between the free and premium tiers to drive conversion. 

And don't get me wrong, I admire CDISC, and everyone I know and have worked with from CDISC is amazing. I want CDISC to thrive, with more resources and the ability to deliver better standards more quickly. For 25 years, it has been doing precisely that, and for 25 years, it has been a truly outstanding organization. 

While companies like Duolingo have proven that this strategy of widening the gap can significantly grow premium user bases and revenue, I'm concerned that this approach may be too risky for CDISC. There are some fundamental differences between revenue-driven companies, such as Duolingo, and CDISC. And I think this change is bad news for the industry, including CDISC member organizations, and here is why:

The Volunteer Model

CDISC is fundamentally driven by volunteers. I'm lucky to work in a company that allows me to spend some time on CDISC tasks. However, I mostly use my personal time to accomplish these tasks. And I am happy to dedicate it to the CDISC mission, as I believe in it. But this change forces me to ask myself a question: Am I developing standards for the global industry, or am I working to make a proprietary product more valuable for CDISC members? After this change, it seems fair to limit my contributions to the time my CDISC member company allocates to me.

The Fate of CDISC CORE

What sets CDISC CORE apart from other validators? While other validators offer faster speed, a greater number of checks, or already-proven stability, there was a critical difference that overshadowed them all: the promise that the CORE engine and its executable rules would be open-source and community-driven. Not anymore. By making the engine and executable rules proprietary, CDISC CORE transforms from a pioneering and universally accessible solution into another proprietary validator. This change is likely to slow the adoption rate and may significantly delay acceptance by regulatory agencies, potentially blocking their use for regulatory submissions altogether.

The Loss of Trust for Open-Source

This change also poses a significant challenge to the open-source community. If an open-source solution was built on the CDISC Library or integrated with CDISC CORE, it is now suddenly restricted to CDISC members. I think it significantly reduces the appeal of CDISC for open-source developers. The timing is particularly confusing, given that the 360i project, which is now actively developed by CDISC, has stated that open-source is supposed to be an essential part of it.

And perhaps the worst outcome is the loss of trust. CDISC explicitly promised that the CDISC CORE engine and executable rules would be open-source and available to all. You can still find this statement on the CDISC CORE page (https://www.cdisc.org/core).

By pulling the plug on CORE and the Library, I unfortunately feel that CDISC has signaled to the community that future commitments cannot be trusted. Why would the open-source developers invest time and effort in tools if they risk being locked behind a paywall in the future? I've spoken to several developers who are creating open-source solutions using CDISC standards, and they experience a similar frustration. As a result, we will have fewer open-source tools. 

Limited Conversion Space

Unlike a mass-market app, the ratio of non-member companies actively using CDISC to member companies is likely not large enough to make a persistent freemium model financially successful. There is not a massive pool of non-members who can become members.

High Entry Barrier

It takes a minute to install an app, it takes months and significant investment to adopt CDISC standards. By providing only PDF versions of the standards and making the initial adaptation phase harder, CDISC reduces the number of potential users and as a result there will be fewer organizations that will become members.

This shift towards making digital versions of the CDISC standards proprietary may result in the development of alternatives. Whether it will come from HL7 Vulcan or something else, I don't know, but I will be listening. No matter how much I admire the people at CDISC, it is much harder to support a mission that, by its actions, chooses to create standards for its members rather than for everyone.