Most enterprise storage sits idle, CTERA study finds

CTERA has published research showing that only 4.4% of enterprise storage is actively used. The findings are based on an analysis of 16 petabytes of production data across 856 file-share scans.

The study examined enterprise network-attached storage environments, including businesses in regulated sectors, and found that most stored information remained untouched for long periods. Overall, 83.1% of total stored capacity was tied up in files that had not been modified for more than a year.

At file level, the pattern was even more pronounced: 97.5% of individual files had not been modified for more than a year, while 88% had not been accessed in that time.

Use over shorter periods was also limited. Only 9.9% of stored data was accessed in any given 90-day period.

The figures suggest many organisations are keeping large volumes of inactive information on primary storage systems designed for day-to-day operational use. That can raise the cost of storing, backing up and protecting data, as businesses continue to apply the same infrastructure and management processes to information that is rarely needed.

The findings also highlight a security concern. Inactive files often remain inside network-accessible environments under existing permissions structures, potentially making far more information available to staff and applications than routine work requires.

The report points to implications for companies preparing internal data for artificial intelligence tools. Large stores of old or dormant information can make it harder for search and retrieval systems to identify the most relevant and current material.

That matters as businesses seek to use AI systems across internal file estates, not just structured databases. If historical material overwhelms active information, the quality of results returned to users may suffer.

CTERA used the research to argue that many IT teams are effectively treating primary storage as an archive. In enterprise data management, this kind of inactive information is often described as ROT, short for redundant, obsolete or trivial data, meaning material that is duplicated or no longer serves a clear operational purpose.

Cost pressure

Keeping that information in front-line storage can create compounding costs across several parts of the IT estate. Businesses pay not only for the storage itself, but also for the backup, protection, monitoring and administration of data that may have little immediate business value.

Those pressures come as companies continue to face rapid growth in unstructured data, including documents, spreadsheets, design files, logs and other content spread across file shares. The report suggests a significant share of that growth may be driven not by active use, but by accumulation.

Aron Brand, Chief Technology Officer at CTERA, said the data showed a mismatch between where information is stored and how often it is used.

"When only 4.4% of capacity is actively used, enterprises are running their most expensive storage tier as what is effectively a cold archive. That creates a multiplier effect across storage and data protection costs, security exposure, and now the quality of information available to AI systems," Brand said.

The findings, CTERA argued, highlight a broader data management problem rather than a narrow storage issue. The challenge is deciding how to retain information while moving less active material off premium systems.

"This points to a fundamental challenge in how organizations think about data management. The answer isn't simply to delete old data, it's to make better decisions about where that data belongs. Information can be retained and protected without living on expensive primary storage," Brand said.

The scale of the data analysed adds weight to the findings because the review covered live production information rather than a small test set. With 16 petabytes reviewed across hundreds of file-share scans, the study offers a snapshot of how enterprise file estates are used in operational settings.

The results also reflect a familiar tension for IT departments. Many organisations are reluctant to remove or relocate data because of regulatory requirements, internal retention policies or uncertainty over future need. Yet leaving it in place can add cost and increase exposure.

For companies investing in AI, that tension is becoming more visible. Search, summarisation and retrieval tools depend on access to data, but also on relevance, making the quality and placement of enterprise information a more pressing operational question.