Legacy software and litigation: why old code still creates new legal problems

Legacy software often lingers quietly behind the scenes, powering core business systems, processing financial transactions, or managing enterprise operations. These older programs—written years or decades ago—can feel like forgotten tools from a previous era. However, in litigation, legacy software is anything but obsolete. It often sits at the center of legal disputes involving intellectual property rights, compliance failures, security breaches, and contractual obligations.

At Eureka Software, we understand that legacy software still matters and can cause significant legal headaches. With over 38 years of experience working across legacy and modern platforms, we’re uniquely positioned to help businesses and legal teams analyze, evaluate, and testify on legacy systems involved in high-stakes litigation.

This article explores why old code continues to generate new legal problems—and how expert analysis is crucial to resolving them.

The Persistence of Legacy Software & Associated Risks

Legacy software refers to older systems that remain used long after their initial development. These programs may be based on outdated programming languages, run on unsupported platforms, or rely on discontinued hardware. Yet, for many companies, these systems continue to operate mission-critical functions.

Whether due to the high cost of replacement, lack of modern alternatives, or integration complexities, businesses frequently choose to maintain legacy systems. But retaining old code comes with significant risks—many of which only become apparent when litigation arises.

1. Intellectual Property Ownership Disputes

Many legacy systems were built in-house by long-departed employees, third-party contractors, or now-defunct vendors. Over time, original documentation may be lost, licensing agreements may expire, and it may become unclear who truly owns the software or its underlying components.

In litigation, questions may arise, such as:

Eureka Software helps answer these questions by conducting forensic reviews of the software’s history, analyzing version control systems, and reviewing documentation (when available) to trace the code’s origins and clarify ownership.

2. Copyright and Trade Secret Infringement

Companies often update or migrate legacy code into modern systems. During that process, proprietary components may inadvertently be copied or repurposed—sometimes by employees who no longer recall where the original code came from. If competing products contain code or functionality that originated in an earlier system, this can lead to claims of copyright infringement or trade secret misappropriation.

We analyze whether the code in question is original or derived from prior work, helping establish the boundaries between public domain knowledge and protected IP.

3. Software Licensing and Compliance Issues

Older systems often depend on open-source libraries or commercial components governed by now-obsolete licensing terms. During audits or lawsuits, businesses may discover:

Because legacy licenses are sometimes no longer supported or easily accessible, identifying violations can be difficult. Eureka Software assists legal teams in interpreting historical licenses and assessing whether usage today is consistent with original agreements.

4. Security Vulnerabilities and Data Breaches

Legacy systems frequently lack up-to-date security measures. They may run on unsupported operating systems, depend on unpatched software, or lack encryption standards that are now common practice.

When a data breach or system failure occurs, the question is often whether the organization met its duty of care. Plaintiffs may argue that outdated systems led to negligence, while defendants must demonstrate that the software was reasonably secure for its time and use.

Our technical experts evaluate the security architecture of legacy systems and provide precise, objective assessments of whether vulnerabilities are avoidable or foreseeable.

5. Contractual Performance Disputes

Legacy software often plays a role in long-term business contracts—particularly in finance, manufacturing, or healthcare industries. When those systems fail, cause downtime, or become incompatible with new technologies, disputes may arise over whether a vendor or partner fulfilled its obligations.

These disputes require an expert evaluation of the software’s capabilities, limitations, and compliance with contract terms. At Eureka Software, we provide performance analysis and expert opinions to determine whether a legacy system delivered what it was contractually expected to provide.

Why Litigation Often Hinges on Expert Analysis

Legacy software cases can be technically and legally complex. Courts, juries, and even experienced attorneys may struggle to understand how decades-old codes impact today’s business and legal environment. That’s where expert witnesses become essential.

At Eureka Software, we bring clarity to these cases by:

Because we continue to work actively in both legacy and modern development environments, we can bridge the gap between past and present—making us uniquely equipped to support software litigation that spans decades of technological change.

Old Code, New Problems — Let Eureka Software Help

Legacy software may be old, but its legal implications are current. From intellectual property conflicts to compliance issues and system failures, outdated code continues to spark complex litigation across industries.

At Eureka Software, we understand that solving these cases requires more than technical know-how—it requires experience, clarity, and the ability to communicate complex findings to non-technical decision-makers. With over 150 litigation cases supported and decades of hands-on development experience, we are the trusted partner for analyzing legacy systems and helping resolve modern legal disputes.

If your case involves aging software, unclear ownership, or outdated technologies, contact Eureka Software to learn how we can provide expert insight and support.