SC-42(5): Collection Minimization

SC-42(5): Collection Minimization requires you to use technical mechanisms that are configured to minimize collection of personal information that is not needed for the stated purpose. To operationalize it fast, you must (1) define “needed” per system purpose, (2) configure collection points (apps, APIs, logs, endpoints) to block or drop unnecessary fields, and (3) keep evidence that the configuration is in place and reviewed. ¹

Key takeaways:

• Treat “minimize collection” as an engineering configuration requirement, not a privacy-policy statement. ¹
• Start with an inventory of collection points, then enforce field-level allowlists and log/telemetry redaction. ¹
• Auditors will ask for proof of configuration and ongoing governance, not intent. ²

SC-42(5): collection minimization requirement sits in the System and Communications Protection family, but it operates like a privacy-by-design control: your systems must be configured so they do not collect personal information about individuals unless there is a defined need. This is easy to over-document and under-implement. A policy that says “we minimize data” will not satisfy an assessor if your application forms, SDKs, API payloads, event streams, and logs still ingest extra fields by default. ¹

For a Compliance Officer, CCO, or GRC lead, the fastest path is to turn this enhancement into a small number of repeatable, testable engineering requirements: (1) each system has an approved purpose and data-need statement, (2) collection points enforce an allowlist of fields aligned to that need, and (3) exceptions are time-bound and approved. You then retain objective evidence that the configuration exists, is deployed, and is periodically revalidated. ²

This page gives you requirement-level implementation guidance you can hand to system owners and audit teams: who it applies to, what to change in operations, what artifacts to keep, common audit traps, and a practical 30/60/90-day rollout plan.

Requirement: SC-42(5) collection minimization

Control objective: Configure technical mechanisms to minimize collection of personal information that is not needed for the system’s purpose. ¹

Plain-English interpretation

You must prevent unnecessary personal information from entering your environment in the first place. That means configuring collection mechanisms (forms, APIs, mobile permissions, agents, telemetry, logging, monitoring, identity flows, and data pipelines) so they only accept and store what is required to deliver the service, meet a documented security need, or satisfy an explicit legal or contractual obligation. ¹

“Minimize collection” is different from “minimize retention.” Retention controls matter, but SC-42(5) focuses on what your systems ingest. If you collect it, you own it: it expands breach impact, discovery scope, subject rights operations, and third-party sharing risk. ²

Regulatory text

“Employ {{ insert: param, sc-42.05_odp }} that are configured to minimize the collection of information about individuals that is not needed.” ¹

Operator translation: Identify the organizationally defined mechanisms (the placeholder refers to your defined set, such as application controls, API gateways, endpoint agents, telemetry collectors, SIEM forwarders, web tags, and identity providers) and configure them to avoid collecting non-required personal information. Your implementation is complete only when the configuration is deployed and you can show evidence that it stays that way. ¹

Who it applies to (entity and operational context)

SC-42(5) is most directly applicable to:

• Federal information systems implementing NIST SP 800-53 controls. ²
• Contractor systems handling federal data (for example, systems supporting federal programs or processing federal information under contract) where 800-53 is the required control baseline or is flowed down. ²

Operationally, it applies anywhere personal information can be collected:

• Product and business systems: registration, onboarding, payments, support, marketing forms.
• Technical collection: authentication/SSO attributes, device fingerprinting, mobile permissions, endpoint/MDM agents.
• Security observability: application logs, audit logs, network telemetry, SIEM events, APM traces, error reporting tools.
• Integrations and third parties: embedded SDKs, analytics tags, customer support tools, identity verification providers.

What you actually need to do (step-by-step)

Step 1: Define “needed” per system (make it assessable)

1. Assign an accountable owner (system owner plus a privacy/security counterpart) for each in-scope system.
2. Document system purpose in one paragraph that an auditor can map to data elements.
3. Create a Data Need Statement listing:
   • Allowed personal data elements (field-level, not “PII” as a category)
   • Purpose for each element (security, functionality, contractual requirement)
   • Source of collection (user-entered, device-derived, third party, inferred)
   • Whether it is required vs optional
4. Define the organizationally defined mechanisms referenced by the placeholder (your official list of collection mechanisms and control points). Keep the list stable; update it via change control. ¹

Deliverable: “SC-42(5) Collection Minimization Standard” + per-system Data Need Statements.

Step 2: Inventory collection points and data flows

Build a practical inventory you can act on:

• Entry points: web forms, mobile screens, call center scripts, PDF uploads, API endpoints.
• Background collection: cookies/tags, SDKs, crash reporters, session replay, A/B testing tools.
• Security logging: auth logs, admin activity logs, WAF logs, reverse proxy logs, database audit logs.
• Pipelines: ETL jobs, event buses, data lake ingestion, SIEM forwarders.

Technique that works: For each system, create a one-page “collection map” that lists the top collection points and the fields captured. You do not need perfect enterprise data lineage to satisfy SC-42(5), but you do need coverage of the mechanisms that actually collect personal information. ²

Step 3: Configure controls to enforce minimization (the core of SC-42(5))

Implement field-level and channel-level minimization at the points where data enters:

A. Forms and UI

• Remove non-required fields; make optional fields truly optional.
• Block free-text fields where structured data works; free text is where sensitive data spills in.
• Add input constraints (length, format) to reduce over-collection.

B. APIs

• Enforce request schema validation.
• Implement allowlists for accepted fields; drop unknown fields server-side.
• For identity attributes, accept only what the authorization decision requires.

C. Logging, telemetry, and monitoring (high-risk collection)

• Redact or tokenize personal data in application logs.
• Disable verbose request/response logging in production unless explicitly approved and time-bound.
• Configure APM and trace tools to suppress headers, payload fields, and query strings that contain personal data.
• Apply SIEM ingestion filters to drop unnecessary personal fields before storage.

D. Endpoint and device collection

• Configure agents to collect only security-relevant telemetry.
• Review mobile permissions; request the minimum set needed for the user-facing feature.

E. Third-party tooling

• Audit embedded SDKs/tags for fields sent off-platform.
• Configure tag managers to prevent collection of personal data by default.
• Contractually restrict collection to documented purposes and required fields where possible.

Implementation rule: If a field is not in the Data Need Statement, it should not be collected. If collection is needed temporarily (debugging, fraud investigation), treat it as an exception with approval and an expiration date. ¹

Step 4: Put governance around exceptions and change

Minimization fails during product iteration unless you control change:

• Require a privacy/security review for any new field or new telemetry event that includes personal information.
• Add a release gate: “new collection fields mapped to Data Need Statement.”
• Maintain an exception register: rationale, approver, scope, and end date.

Step 5: Test and continuously validate

Auditors like objective checks:

• Run automated tests to confirm APIs reject unknown fields.
• Use log scanning rules to detect patterns (emails, SSNs, tokens) in logs and alerts.
• Sample event payloads from telemetry streams for prohibited fields.
• Re-validate after major releases and when third-party SDK versions change.

Required evidence and artifacts to retain

Keep evidence that shows both design and operation:

Artifact	What it proves	Owner
SC-42(5) Collection Minimization Standard	Your defined mechanisms and rules for “needed”	GRC / Privacy / Security
Per-system Data Need Statement	The allowlist of personal data elements and purposes	System Owner
Collection point inventory / collection map	You know where collection happens	Engineering / Architecture
Configuration evidence (screenshots, IaC, config files)	Mechanisms are configured to minimize collection	Engineering / SecOps
Log/telemetry redaction rules	Sensitive fields are suppressed before storage	SecOps / Observability
Change tickets / PRs	Minimization is enforced through change control	Engineering
Exception register	Controlled deviations with approval	GRC / Privacy
Test results / monitoring alerts	Ongoing validation of minimization	SecOps / QA

A simple way to stay assessment-ready is to map SC-42(5) to a control owner, an implementation procedure, and recurring evidence artifacts, then schedule evidence refresh. ¹

Common exam/audit questions and hangups

Expect these questions from assessors evaluating the sc-42(5): collection minimization requirement:

• “Show me where you defined what data is needed for System X, and who approved it.” ²
• “Where are the technical mechanisms, and what are their configurations?” ¹
• “How do you prevent engineers from logging request payloads that contain personal data?” ²
• “How do you control third-party tags/SDKs and what they collect?” ²
• “How do you detect drift after releases?” ²

Hangup to plan for: teams often present a data retention schedule as minimization evidence. Keep both, but don’t confuse them. ²

Frequent implementation mistakes (and how to avoid them)

1. Mistake: Relying on policy language without configuration proof.
   Fix: require config artifacts (IaC, policy-as-code, screenshots, exported settings) tied to each collection mechanism. ¹

2. Mistake: Ignoring logs and telemetry.
   Fix: treat observability as a collection mechanism; enforce redaction, sampling controls, and ingestion filters. ²

3. Mistake: “Optional fields” that still get collected via SDK defaults.
   Fix: verify outbound events and third-party destinations; configure SDKs to disable automatic capture. ²

4. Mistake: Allowing “temporary debugging” to become permanent.
   Fix: time-bound exceptions with an end date and a rollback task in the sprint backlog.

5. Mistake: Defining “needed” at too high a level.
   Fix: write allowlists at the field level. An assessor cannot test “contact info” but can test “email address collected on signup form.” ²

Enforcement context and risk implications

No public enforcement cases were provided in the source catalog for SC-42(5). ¹

Risk still matters operationally. Over-collection increases:

• Incident impact scope (more sensitive data in more places).
• eDiscovery and internal investigation burden.
• Third-party exposure (data sent to tools you do not fully control).
• Access control and monitoring complexity (more data types needing protection). ²

Practical 30/60/90-day execution plan

Days 0–30: Establish scope, owners, and the “needed data” baseline

• Name a control owner and RACI for SC-42(5) across product, engineering, SecOps, and privacy.
• Publish the Collection Minimization Standard, including your list of “organizationally defined mechanisms” that must be configured. ¹
• Pick a small set of high-volume systems (customer onboarding, authentication, primary API, logging pipeline).
• Produce Data Need Statements for those systems and get approvals.
• Identify quick wins: remove unused form fields, disable verbose logging, and restrict API schemas.

Days 31–60: Implement configuration controls and exception process

• Add schema validation and field allowlists to APIs for in-scope systems.
• Implement logging redaction and SIEM ingestion filters for personal fields.
• Create the exception register workflow in your ticketing system and require approvals.
• Add release gates: “new data element requires Data Need Statement update + approval.”

Days 61–90: Prove operational maturity and reduce drift

• Create automated checks (API tests for unknown fields, log scanners for sensitive patterns).
• Run a configuration review for third-party SDKs/tags and document settings exports.
• Conduct an internal assessment walkthrough: pick one system and trace from Data Need Statement to configuration evidence to test results.
• Set a recurring evidence cadence and map SC-42(5) to owner, procedure, and artifacts in your GRC system so audits are a pull, not a scramble. Daydream can help you maintain that mapping and evidence rhythm across systems as the environment changes. ¹

Frequently Asked Questions

Does SC-42(5) mean we can’t collect optional user profile fields?

You can collect optional fields if you can justify the need and document the purpose and approval in the system’s Data Need Statement. The control expectation is to minimize collection of information that is not needed and to configure mechanisms accordingly. ¹

Are logs in scope for “collection minimization”?

Yes. Logs and telemetry are collection mechanisms because they ingest and store information about individuals, often incidentally. Configure redaction and disable payload logging that captures personal data unless it is explicitly needed and approved. ²

What counts as a “mechanism” we must employ and configure?

The control text references “organizationally defined” mechanisms, meaning you must define which technical control points you rely on (for example, API gateways, schema validators, logging libraries, SIEM filters) and then show how they are configured to minimize collection. ¹

How do we handle third-party SDKs that auto-collect device data?

Treat the SDK configuration as part of your collection mechanism inventory. Disable default auto-capture features where possible, document what remains, and approve only what is needed for your stated purpose. ²

Is data minimization the same as data retention minimization?

No. SC-42(5) is about minimizing collection, meaning preventing unnecessary data from entering your systems. Retention and disposal are separate operational obligations that may be covered by other controls and policies. ¹

What evidence is most persuasive to an assessor?

Configuration artifacts (IaC, exported settings, code snippets for allowlists/redaction) tied to a documented Data Need Statement, plus test results that show the controls work in production. Policies help, but configuration and validation win audits. ²

Footnotes

1. NIST SP 800-53 Rev. 5 OSCAL JSON

2. NIST SP 800-53 Rev. 5