SIG vs SIG Lite: Scope, Structure, and When Each One Applies

Key Takeaways

• The SIG (Standardized Information Gathering) questionnaire is a comprehensive vendor risk assessment with several hundred questions across 18 risk domains. SIG Lite is a streamlined version with roughly a quarter of the questions, designed for lower-risk vendor relationships.
• Both are maintained by Shared Assessments and updated annually. Recent versions align with current NIST, ISO 27001, and GDPR requirements.
• Standardised questionnaire formats like the SIG have become one of the dominant tools in enterprise third-party risk management programmes.
• Which version you receive depends on how the buyer classifies your risk tier, not on your company size or maturity.
• Completing either version gets dramatically faster once you maintain a single, well-structured knowledge base of your security controls and policies.

What Are the SIG and SIG Lite Questionnaires?

The SIG questionnaire is a standardised vendor risk assessment created and maintained by Shared Assessments, a member-driven organisation focused on third-party risk management. It gives buyers a structured way to evaluate whether a vendor meets their security, privacy, and operational requirements before signing a contract. SIG Lite is the abridged version of the same questionnaire, covering the same risk domains at a higher level with fewer detailed questions.

If you sell software to mid-market or enterprise buyers, you will almost certainly encounter one of these two versions during a deal. The SIG has become one of the most widely adopted assessment frameworks in B2B procurement, alongside SOC 2 reports and custom security questionnaires. Getting through it quickly and accurately can directly affect whether a deal closes on time or stalls in procurement review.

Full SIG vs SIG Lite: What Exactly Is Different?

The core difference comes down to depth and detail. Both questionnaires cover the same 18 risk domains, but the full SIG asks granular follow-up questions within each domain, while SIG Lite stays at the control-objective level.

The 18 SIG Risk Domains

Both versions generally assess the following areas (note that Shared Assessments updates domain labels periodically, so always verify against the specific version year you receive):

1. Enterprise Risk Management
2. Security Policy
3. Organisational Security
4. Asset and Information Management
5. Human Resources Security
6. Physical and Environmental Security
7. IT Operations Management
8. Access Control
9. Application Security
10. Cybersecurity Incident Management
11. Operational Resilience
12. Compliance and Legal
13. Endpoint Device Security
14. Network Security
15. Privacy
16. Threat Management
17. Server Security
18. Cloud Hosting Services

The full SIG goes deep into each of these domains. For example, in the Access Control domain, the full SIG might ask 40 to 60 questions covering password policies, privileged access management, multi-factor authentication implementation, access review cadence, and de-provisioning procedures. SIG Lite covers the same domain but with a smaller set of higher-level questions that ask whether you have controls in place without requesting the same procedural detail.

Side-by-Side Comparison

Completion times vary significantly depending on team size, the state of your existing documentation, and how many domains are in scope. The estimates above reflect what we have observed across teams completing these for the first time without automation.

The Risk Tier Model: Why You Get One Version Over the Other

You do not get to choose which version a buyer sends you. The decision sits with the buyer’s risk or procurement team, and it is based on how they classify your vendor risk tier. Understanding this classification helps you anticipate what is coming and prepare accordingly.

Most enterprise TPRM programmes use a tiered model that looks something like this:

The Three-Tier Vendor Risk Classification

Tier 1 (Critical/High Risk): Vendors who handle sensitive data, have system-level access, or provide services that would materially disrupt the buyer’s operations if they failed. These vendors receive the full SIG. Examples: your cloud infrastructure provider, your payment processor, a SaaS platform that stores customer PII.

Tier 2 (Moderate Risk): Vendors with some access to internal systems or non-critical data. These vendors typically receive SIG Lite or, in some cases, the full SIG with reduced scoping. Examples: an analytics tool with read-only access to anonymised data, a project management platform used by internal teams.

Tier 3 (Low Risk): Vendors with no access to sensitive data or systems. These vendors usually get a short custom questionnaire or no questionnaire at all. Examples: office supply vendors, marketing agencies with no system access.

If your product touches customer data or integrates with production systems, expect the full SIG.

Formal vendor tiering helps buyers focus their assessment effort on the relationships that carry the most risk. For you as a vendor, the practical takeaway is that your risk classification determines the questionnaire version, and your product’s data access patterns are the single biggest factor in that classification.

The SIG Scoping Sheet: Your Most Underused Advantage

Both SIG and SIG Lite include a scoping sheet at the front of the workbook. This is one of the most valuable and most overlooked parts of the entire questionnaire. The scoping sheet lets you mark which of the 18 domains are relevant to your service, and it can legitimately reduce the number of questions you need to answer by a substantial margin.

Teams that use the scoping sheet effectively often cut their SIG completion time by roughly a third, simply by not answering questions that do not apply to their engagement.

Here is how to use it well:

Step 1: Review the Scoping Sheet Before Answering Anything

Do not jump straight into the domain tabs. Start with the scoping sheet and honestly assess which domains apply to your product and service delivery model. If you do not operate physical data centres, the Physical and Environmental Security domain can be scoped out (assuming you can point to your cloud provider’s controls instead).

Step 2: Document Your Rationale

For every domain you mark as out of scope, add a brief note explaining why. “We use AWS eu-west-1 for all hosting; physical security controls are managed by AWS and documented in their SOC 2 Type II report” is far more credible than a blank “N/A.”

Step 3: Confirm Scoping With the Buyer

Before you spend hours answering questions, send the completed scoping sheet to the buyer’s security or procurement team and ask them to confirm. This takes five minutes and can save you days of unnecessary work. Most buyers appreciate this because it shows you understand the process.

Completing the SIG Efficiently: The Knowledge Base Approach

Whether you are facing SIG or SIG Lite, the real time sink is not the questionnaire format itself. It is the process of finding accurate, current answers across your team. The first time a growing SaaS company encounters a full SIG, the typical workflow looks something like this: the CTO or head of security opens the spreadsheet, reads through hundreds of questions, realises they need input from engineering, DevOps, HR, and legal, and then spends the next two weeks chasing people down over Slack.

The pattern breaks when you centralise your security knowledge into a single, maintained source of truth. This is the core idea behind tools like ResponseHub: rather than answering each new questionnaire from scratch, you build a knowledge base from your existing policies, past questionnaire responses, and control documentation. When a new SIG arrives, AI matches questions to your existing answers, and you review and approve rather than write from zero.

In our experience, a well-maintained knowledge base can bring subsequent SIG completions down to a fraction of the original time. Over the course of a year with multiple enterprise deals in the pipeline, that is the difference between a security team spending a quarter of their time on questionnaires and spending a small, predictable slice of it.

Build the knowledge base once, maintain it continuously, and every future SIG becomes a review exercise rather than a research project.

What Good SIG Answers Look Like

Buyers reviewing your SIG responses are looking for specificity and evidence. A strong answer pattern follows this structure:

1. State the control clearly: “We enforce MFA on all production systems and corporate accounts.”
2. Name the implementation: “MFA is managed through Okta with hardware key support via YubiKey.”
3. Reference the policy: “This is documented in our Access Control Policy, Section 4.2.”
4. Note the review cadence: “Access permissions are reviewed quarterly by the engineering lead.”

Vague answers like “Yes, we have this control” get flagged for follow-up. Specific answers move the deal forward.

Common Mistakes When Completing SIG Questionnaires

Having seen hundreds of SIG completions across different companies, a few patterns consistently cause problems:

Treating N/A as a shortcut. Marking questions as not applicable without explanation raises red flags with reviewers. Every N/A should include context.

Copy-pasting answers from a different framework. SOC 2 controls and SIG questions overlap but are not identical. An answer written for a SOC 2 audit may not address what the SIG question is actually asking. Map your responses to each question specifically.

Letting answers go stale. If your SIG responses reference a tool you replaced six months ago or a policy that has been rewritten, the reviewer will notice the inconsistency. This is where a maintained knowledge base pays for itself repeatedly.

Ignoring the “Additional Information” fields. Both SIG versions include space for supplementary context. Use these fields to link to your SOC 2 report, ISO 27001 certificate, or trust page. Proactively providing evidence reduces back-and-forth and can shave entire review cycles off the process.

Skipping internal review. Before submitting, have someone who did not write the answers read through them. Fresh eyes catch contradictions between sections that the original author will miss.

Why Getting Good at the SIG Pays Compound Returns

The SIG is not going away. If anything, its adoption is increasing as more enterprise buyers standardise their TPRM programmes around established frameworks rather than building custom questionnaires from scratch. Shared Assessments has reported steady growth in SIG adoption year over year, with particularly strong uptake in financial services, healthcare, and technology sectors.

Every hour you invest in building clean, well-documented SIG responses is an hour you do not have to spend next quarter. Your answers become reusable assets. Your policies get tighter as a side effect. And your sales team gets to tell prospects “we can turn around a SIG in 48 hours” instead of “we will need a few weeks.” That speed becomes a competitive advantage, especially in deals where multiple vendors are being evaluated simultaneously and the first one through procurement review gets the contract.

The companies that treat security questionnaires as a repeatable process rather than an ad-hoc fire drill are the ones closing enterprise deals consistently. Whether you are staring down your first SIG Lite or your fifteenth full SIG, the principle is the same: build the system once, maintain it continuously, and let it compound.

Frequently Asked Questions

Can I submit a SIG Lite if the buyer asked for a full SIG?

No. If a buyer has classified you as a high-risk vendor and sent the full SIG, submitting the Lite version instead will likely delay your deal and may signal that you are not taking their risk process seriously. If you believe the scoping is incorrect, raise it with the buyer’s security team directly and explain your rationale. They may agree to adjust, but the decision is theirs.

Do I need a Shared Assessments membership to access the SIG?

The SIG questionnaire is distributed by Shared Assessments and typically requires a membership or licence to access the official template. However, most vendors receive the SIG directly from their buyer’s procurement team as part of the sales process. You do not need your own membership to complete a SIG that a buyer sends you.

How often does the SIG get updated?

Shared Assessments releases an updated version of both SIG and SIG Lite annually. Each new version incorporates changes in regulatory requirements, emerging threat categories, and industry feedback. If you are completing a SIG, check the version number on the workbook. Buyers occasionally send outdated versions, and noting this diplomatically can be helpful.

Does completing a SIG replace the need for SOC 2 or ISO 27001?

No. The SIG is a self-attestation questionnaire, meaning your answers are not independently verified by a third party. SOC 2 and ISO 27001 involve independent audits. Most enterprise buyers want both: a certification or audit report as baseline evidence, and a completed SIG to assess controls specific to their engagement. The SIG and your audit reports are complementary, not substitutes.

How does ResponseHub help with SIG questionnaires?

ResponseHub builds an AI-powered knowledge base from your existing policies, past questionnaire responses, and security documentation. When you upload a new SIG or SIG Lite, the platform matches each question to your existing verified answers and auto-completes the questionnaire. You review and approve the responses rather than writing from scratch, which typically reduces completion time from days to hours.

Is SIG Lite less rigorous than the full SIG?

SIG Lite covers the same 18 risk domains as the full SIG. It matches the full version in rigor; it simply operates at a higher level of abstraction. The questions focus on whether controls exist at the objective level rather than probing implementation specifics. A thoughtful, well-documented SIG Lite response demonstrates the same level of security maturity as a full SIG, just with less procedural detail.