Software project failure liability — UK IT consultants and developers
Software project failure is the single largest single claim category for UK IT consultants and developers. Understanding how failure liability is allocated between consultant and client — and how PI wording responds — is essential to structuring cover and to defending claims when they arise.
How software failure claims typically arise
Missed go-live date
Project overruns delivery deadline. Client experiences business impact from delay. Where consultant is contracted on fixed-price fixed-date basis, exposure follows.
Functional deficiency at go-live
System delivered on time but doesn't meet functional requirements. Client faces remediation cost, business impact, or complete re-scoping.
Post-live production failure
System delivered and accepted; production failure occurs later. Root cause allegedly traces back to consultant's design or implementation decision.
Data loss or corruption
System error during migration or operation causes client data loss. Recovery costs and business-interruption claims typical.
Contract structure and liability allocation
Fixed-price contracts
Consultant bears delivery risk. Higher rating on PI. Client typically won't accept caps on liability. Fixed-price is the highest-exposure structure.
Time-and-materials contracts
Client bears delivery risk. Lower rating on PI. Consultant compensated for actual work performed. Failure claims typically limited to negligence, not delivery-timing.
Phased-milestone contracts
Hybrid structure. Fixed elements for defined milestones, T&M for scope extensions. Risk allocation varies by phase.
Outcome-based contracts
Consultant paid on achievement of defined business outcome. Highest-risk structure for consultant.
PI wording concerns
- Fixed-price project cover — some wordings restrict cover on fixed-price large-project work.
- Software design and delivery activity must be specifically declared and covered.
- Consequential loss treatment — PI typically covers direct damages; consequential loss (client business interruption from failure) may be restricted.
- Liquidated damages clauses in client contracts — PI response varies. Some wordings exclude contractually-assumed liability beyond common law.
- Product liability — software as product — distinct from PI in some wordings. IP-supply activity should be reviewed.
Defending software failure claims
The defence follows the underlying documented process. Documented requirements, change control, sign-off gates, testing evidence, acceptance sign-offs all matter.
Where documentation is thin or absent, the consultant is defending both the substantive claim and the process failure simultaneously. Documentation discipline is a PI-defence asset.
Case law and industry references
SAAMCo scope-of-duty framework
The Supreme Court's SAAMCo (South Australia Asset Management v York Montague) framework applies. Consultant's liability limited to loss arising from the specific scope of the duty assumed — not all consequential loss following breach.
BSkyB v EDS [2010]
The famous UK software-failure case. Held that a supplier can be liable for misrepresentation and fraudulent negligent statements in the sales process, not just delivery breach.
Software Solutions Partners v HMRC [various]
HMRC contract-failure litigation illustrates public-sector software project failure risk and how it plays out over multi-year litigation.