By NHI Mgmt Group Editorial TeamBased on Ground Labs: “Ensuring data security in mergers and acquisitions (M&A)” (February 24, 2026)

TL;DR: M&A activity rose sharply in 2025, with deal value up 40% and volume up 7%, while 40% of acquirers found major cybersecurity issues during post-acquisition integration and fewer than 10% of deals included cyber due diligence, according to Ground Labs and IMAA. Data discovery has become a control for valuation, liability, and integration risk, not just a compliance exercise.


At a glance

What this is: This is a blog post arguing that data discovery has become a deal-risk control in M&A because it exposes hidden security, regulatory and integration liabilities before they distort valuation.

Why it matters: It matters to IAM and data security practitioners because post-close integration often inherits undiscovered sensitive data, legacy access and governance gaps that widen operational and contractual risk.

By the numbers:

  • 40% of acquirers discovered major cybersecurity issues during post-acquisition integration, according to Ground Labs.
  • Less than 10% of deals incorporated cyber due diligence during the M&A process, according to Ground Labs.
  • 2025 saw a surge in deals that increased in both value by 40% and volume by 7%, according to Ground Labs.
  • Marriott was fined $23.8m by the UK ICO and agreed a $52m settlement in the US, according to Ground Labs.

Context

Data discovery in M&A is the practice of locating sensitive, regulated and redundant data before, during and after a transaction so the parties know what risk they are inheriting. In this article, Ground Labs frames that work as a security and deal-control issue, not just a cleanup exercise, because undiscovered data can change valuation, liability and integration cost.

The article's core governance point is that acquirers often discover security and compliance debt only after close, when leverage has already shifted and remediation is more expensive. For IAM, PAM and data security teams, the relevant question is not whether the target has data, but whether anyone can prove where sensitive data sits, who can reach it and how fast exposure can be reduced after integration.


Key questions

Q: What breaks when data discovery is not in place during M&A due diligence?

A: When discovery is missing, the buyer cannot see what sensitive data, legacy systems or inherited access paths it is acquiring. That leads to inaccurate valuation, underestimated remediation cost and a much higher chance of finding compliance or breach liabilities only after close, when options are more limited.

Q: Why does hidden data increase regulatory and liability risk after an acquisition?

A: Hidden data makes it impossible to judge whether the target is carrying personal, regulated or contractually sensitive information that triggers CCPA, GDPR or PCI DSS obligations. If the buyer cannot evidence scope and access, it inherits unclear accountability, larger remediation cost and possible deal adjustments or holdbacks.

Q: What are the signs that M&A data governance is failing?

A: Warning signs include unclear data inventories, no documented access map for sensitive datasets, heavy reliance on manual discovery and late-stage security findings during integration. If these show up, the organisation is likely discovering risk after it has already taken ownership of the environment.

Q: How should buyers and sellers divide responsibility for pre-close data hygiene?

A: Sellers should remove redundant data, surface sensitive records and show where exposure exists before diligence accelerates. Buyers should validate those claims, test for regulatory exposure and tie any unresolved risk to price, remediation commitments or deal conditions.


Technical breakdown

Why data discovery becomes a transaction control

Data discovery turns into a transaction control because M&A combines two or more imperfect environments, each with its own data stores, access paths and retention habits. The technical challenge is not only locating files and databases, but also mapping where personal data, regulated records and sensitive business content sit across cloud and on-premises systems. Without that inventory, acquirers inherit unknown exposure and sellers cannot evidence hygiene. That makes discovery an input to diligence, integration planning and post-close remediation, rather than a back-office reporting task.

Practical implication: Treat discovery outputs as diligence evidence that informs price, scope and remediation sequencing before systems are merged.

How hidden data creates inherited identity and access risk

Sensitive data rarely exists in isolation. It is tied to access controls, service accounts, application permissions and integration workflows that may already be over-permissioned or poorly documented. If a target company cannot show where data resides and which identities can reach it, the buyer inherits unresolved access paths along with the data itself. That creates governance blind spots across IAM, PAM and NHI estates because accounts, tokens and integrations can continue to access datasets long after the transaction closes.

Practical implication: Use discovery findings to map sensitive datasets to the human and non-human identities that can reach them.

Why post-close discovery matters for migration and remediation

The risk does not end at close. Post-acquisition integration often includes cloud migration, platform consolidation and service continuity work, all of which can surface data that was not visible during diligence. Scheduled monitoring helps teams catch new exposures early, support incident triage and produce audit evidence for regulators and boards. In practice, discovery becomes a continuous control across change windows, not a one-time scan before signing.

Practical implication: Build continuous discovery into integration and migration plans so new exposure is detected before consolidation completes.


Threat narrative

Attacker objective: The practical objective is to exploit inherited complexity and undocumented access so sensitive data remains exposed long enough to create financial, legal or operational damage.

  1. Entry occurs when acquired environments contain unknown sensitive data stores, legacy systems or inherited access paths that were never mapped during diligence.
  2. Credential and access abuse follows when over-permissioned accounts, service identities or stale integration paths can still reach data after the deal closes.
  3. Impact appears as regulatory exposure, deal holdbacks, integration delays, remediation cost and, in some cases, post-close breach liability.

NHI Mgmt Group analysis

Data discovery is now a valuation control, not a housekeeping task: M&A teams are no longer just buying a business, they are buying its data exposure profile. If sensitive data, regulated records and legacy access cannot be located quickly, the buyer is pricing blind and the seller is negotiating without evidence. Practitioners should treat discovery results as deal inputs, not post-close cleanup artefacts.

The inherited-risk problem is an identity problem as much as a data problem: Data liabilities persist because identities, integrations and service accounts often survive the transaction longer than the systems that created them. That makes IAM, PAM and NHI visibility central to integration, since data that is found but still broadly reachable remains a live exposure. The governance failure is assuming storage inventory alone is enough.

Pre-close due diligence should be evidence-led and not assumption-led: The article's figures point to a market where cybersecurity issues are often found late and cyber diligence is still absent in too many deals. That means acquirers need proof of sensitive data location, access scope and regulatory exposure before signing. Buyers that cannot verify these basics should assume their integration and liability model is incomplete.

ROT data reduction is a deal-risk concept: Redundant, obsolete and trivial data expands blast radius, slows integration and makes liability harder to quantify. Removing it before close reduces what the buyer has to inherit and what the seller has to defend. Practitioners should use data minimisation as a transaction control, not only as a storage-efficiency measure.

From our research library:

What this signals

Data discovery has become a control for integration risk because post-close visibility gaps create liability that legal and technical teams inherit together. M&A programmes should assume that any unknown data store or undocumented access path will become more expensive after signing, not less.

M&A data discovery: This is the point where transaction governance, access governance and data governance converge. If sellers cannot show what data exists and buyers cannot map who can reach it, the deal is already carrying unmanaged exposure.

The spending pressure around AI and data security reinforces the same pattern: transaction speed is increasing, but control quality is not keeping pace, so discovery has to move earlier in the lifecycle.


For practitioners

  • Inventory sensitive data before signing Map regulated, personal and business-critical data across on-premises and cloud systems before the transaction terms are finalised.
  • Tie data stores to access paths Document which human and non-human identities, integrations and service accounts can reach each sensitive dataset.
  • Use discovery outputs in diligence decisions Translate discovery findings into deal terms, remediation priorities and estimates for post-close integration cost and regulatory exposure.
  • Reduce ROT data before integration Remove redundant, obsolete and trivial data so the buyer inherits less unnecessary exposure and fewer migration dependencies.

Key takeaways

  • M&A creates a visibility problem as much as a valuation problem, because unknown data and undocumented access can survive the deal and inflate liability.
  • The article shows that discovery is useful before close, at close and after integration, because each phase reveals different categories of exposure.
  • Removing redundant data and mapping access paths are the controls most likely to reduce inherited risk and improve confidence in the transaction.

Standards & Framework Alignment

This section maps relevant standards and security frameworks to the operational risks and controls described in this guidance.

NIST CSF 2.0, NIST SP 800-53 Rev 5, CSA Cloud Controls Matrix and CIS Controls v8 set the governance and control requirements practitioners need to meet.

FrameworkControl / ReferenceRelevance
NIST CSF 2.0PR.DS-01 — Data-at-RestThe article centres on locating and protecting sensitive data before and after M&A integration.
PR.AA-05 — Access Permissions, Entitlements and AuthorizationsInherited data risk is amplified when buyers cannot see which identities can reach target datasets.
Recommendation — Map discovered sensitive data to PR.DS-01 and prioritise datasets that carry regulatory or contractual exposure. Use PR.AA-05 to validate who can access each sensitive dataset before systems are integrated.
NIST SP 800-53 Rev 5AU-9 — Protection of Audit InformationDiscovery evidence and remediation records need to survive diligence and board-level assurance.
Recommendation — Protect discovery and remediation evidence under AU-9 so integration decisions remain auditable.
CSA Cloud Controls MatrixDSP — Data Security & PrivacyThe article focuses on data discovery across cloud and on-premises environments during acquisition.
Recommendation — Apply DSP controls to inventory sensitive data and validate its handling across the merged environment.
CIS Controls v8CIS-3 — Data ProtectionThe post emphasises reducing data exposure and limiting inherited risk through discovery and cleanup.
Recommendation — Use CIS-3 to reduce exposed data and remove redundant records before integration begins.

Key terms

  • Data Discovery: Data discovery is the process of finding where information lives across cloud, SaaS, endpoints, backups, and analytics systems. In practice, it creates the inventory that makes classification, access decisions, recovery planning, and AI governance possible rather than speculative.
  • Redundant, Obsolete, and Trivial Data: Redundant, obsolete, and trivial data, often shortened to ROT, is information that no longer delivers business value but still consumes storage and creates risk. It is a common source of governance drift because it remains accessible even after its operational purpose has passed.
  • Deal Risk: The likelihood that hidden security, compliance or operational issues will affect price, timing, integration effort or post-close liability. In this context, deal risk is not abstract, because undiscovered data and access paths can directly change what the buyer inherits.
  • Post-Acquisition Integration: The phase in which acquired systems, data and processes are merged into the buyer's environment. It is often where hidden data exposure, access problems and control gaps become visible because two governance models have to coexist and then be consolidated.

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NHIMG Editorial Note
Published by the NHIMG editorial team on August 18, 2026.
Updated on October 12, 2026.
NHI Mgmt Group, the independent authority on Non-Human Identity, IAM, and Agentic AI security. nhimg.org