Baden, Switzerland – Modern Macromolecular crystallography (MX) relies on a foundation of trusted, highly optimized software to translate raw diffraction images into meaningful structural biology insights. For decades, XDS – the software program developed by Wolfgang Kabsch –  has served as a critical component in this workflow. Max Planck Innovation and Wolfgang Kabsch have chosen to entrust DECTRIS with the long-term stewardship, distribution, and support of XDS through an exclusive licensing agreement.

Through this transition, DECTRIS ensures that (a) XDS remains freely available to academic researchers without any version-bound time restrictions, (b) establishes a transparent and stable licensing framework for commercial users, and (c) introduces a rigorous reproducibility framework to track algorithmic consistency across future hardware generations.

A Trusted Standard in MX Data Processing

The connection between DECTRIS and XDS spans over 20 years. When Hybrid Photon Counting (HPC) detectors introduced measurements with zero readout noise, standard algorithms failed because they relied on the existence of a background. XDS was the first software program to adapt to this unprecedented noise-free MX data. By making our detectors usable for routine analysis, XDS fundamentally drove the early success of HPC technology. Stepping in to maintain XDS today is our way of saying “thank you” to the author Wolfgang Kabsch for that critical support.

Wolfgang Kabsch has been developing and maintaining XDS since its first release in 1986 – since then XDS has become an indispensable tool in structural biology. The only other individual to contribute to the core code over its history is Kay Diederichs. Renowned for its stability, reliability, and performance, XDS is rightfully considered one of the gold standards for MX data processing. Today, the datasets behind more than 50% of the MX structures collected with synchrotron radiation that are deposited in the Protein Data Bank (PDB) have been processed with XDS.

“Since 1986, XDS has grown alongside the crystallography community. Ensuring its stability for the next generation of researchers required a partner who deeply understands the science, data and the beamlines. DECTRIS has been a trusted partner for decades, and I am confident in their stewardship of the code for the next decades to come.”

Dr. Wolfgang Kabsch, Author of XDS, Max-Planck Heidelberg

Why Long-Term Availability Matters Now

As structural biology and particularly Protein Crystallography increasingly moves towards automated, even autonomous pipelines, the availability of foundational tools is critical. Following discussions in mid-2025, it became clear that the MX community would strongly benefit from a solution to ensure both the long-term availability and the scientific reliability of XDS. DECTRIS was approached to take action, and we recognized that maintaining XDS is integral to serving the community and ensuring the uninterrupted future operation of MX beamlines worldwide.

What Changes for the Academic Community

For academic researchers and synchrotron facilities, our priority is to remove friction and guarantee access. Under the new agreement with Max Planck Innovation, DECTRIS is contractually bound to provide XDS free of charge for academic use.

DECTRIS is removing the 12-month expiration constraint that previously forced academics to continuously update their software. There will be a single version of XDS for both academic and proprietary use, which will be publicly downloadable upon registration. Academic users will enjoy unlimited free use. Furthermore, academic labs and beamlines that process data on behalf of commercial customers holding a valid XDS license will not need to purchase a separate license themselves.

“The scientific integrity of structural biology relies on software that processes data predictably and accurately. By removing the version expiration of the academic license, and by driving the reproducibility project, DECTRIS is providing the structural biology community with continuity, and enables reproducibility of results.”

Prof. Kay Diederichs, Professor of Molecular Bioinformatics, University of Konstanz

What Changes for Commercial Users

For pharmaceutical companies, biotech firms, and contract research organizations (CROs), XDS remains a vital component of drug discovery workflows. Moving forward, DECTRIS holds the worldwide exclusive license for commercial sales and distribution.

Proprietary users will transition to a clear, predictable yearly licensing model. Any existing XDS license procured from Max Planck in the past may still be used – for updated versions, a new license will have to be acquired from DECTRIS.*

Preserving the Code, Advancing Reproducibility

As of today, DECTRIS does not intend to undertake major algorithmic developments. We will not rewrite or alter the core algorithms that the community trusts. Instead, our technical adaptations will focus strictly on ensuring XDS runs reliably on state-of-the-art hardware, remains compatible with both DECTRIS and non-DECTRIS file formats, and interprets current and future detector and experimental metadata.

“Taking on the distribution and support of XDS is a profound responsibility. We are not here to change algorithms – our mission is to protect this vital piece of software infrastructure for the community, support the scientists who rely on it, and guarantee that academic users have unfettered, permanent access to their workflows.”  

Clemens Schulze-Briese, Executive Director, DECTRIS 

Furthermore, DECTRIS is leading an extensive XDS reproducibility project. This initiative will enable the automatic tracking and documentation of XDS behavior across different versions. By hosting stable and prepackaged versions of XDS and reference datasets in the DECTRIS CLOUD, we provide an analysis framework that allows anyone to inspect the software’s performance in detail. A working group – featuring Gleb Bourenkov, Gerard Bricogne, Ashwin Chari, Kay Diederichs, Wolfgang Kabsch, and Clemens Vonrhein – is actively guiding this framework.

Acknowledgements

Along this journey of scientific rigor, technical troubleshooting, and legal challenges, we have had the privilege to be supported by several scientists who have all dedicated immense time, energy, and resources to ensuring the best possible outcome for the community. Amongst many, we want to particularly thank and acknowledge: Ashwin Chari (Max Planck Göttingen); Clemens Vornrhein, Gerard Bricogne, and the entire Global Phasing Limited team; Gleb Bourenkov (EMBL Hamburg); and of course Kay Diederichs (University of Konstanz, retired) and Wolfgang Kabsch (Max Planck Heidelberg, retired).

*DECTRIS and Max Planck Innovation do not allow any reselling and sublicensing of XDS.

“Crystallographers need to trust that their data processing is reliable and reproducible. By providing reference datasets and stable versions of XDS, we’re making it easy for the community to verify the stability of results over future software and hardware changes, ensuring the best data quality. ”

Hans Gildenast, Application Scientist Crystallography, DECTRIS

Further Information

Download the software, read the documentation, learn more and stay up-to-date on new versions at https://www.dectris.com/en/detectors/XDS

Do you have any questions? Come to the open Q&A session on July 2nd, between 13:00-15:00 (CEST, Zürich Time Zone): link