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Professional Judgment Documentation: The Audit Survival Guide

FairValueX Team · 8 min read

The Uncomfortable Reality: Every 409A valuation involves 15-20 material judgment decisions. In most deliverables, fewer than half are documented. When an auditor asks "why did you select this methodology?" or "how did you determine this DLOM?", the valuator must reconstruct reasoning from memory — if they can. This is the single biggest source of audit friction and supplemental requests.

What Is Professional Judgment in Valuation?

Professional judgment refers to every decision in the valuation process where a reasonable professional could have chosen differently. It's not the mathematics — it's the choices that frame the mathematics.

Examples of judgment decisions in a typical 409A:

  • Which valuation approaches to use (and their relative weighting)
  • Which comparable companies to include (and which to exclude)
  • What adjustments to make to the discount rate
  • What company-specific risk premium (CSRP) to apply
  • Which equity allocation method to use (OPM, Backsolve, PWERM)
  • What DLOM methodology and magnitude to apply
  • How to weight multiple scenarios in PWERM
  • What volatility peers to select and what measurement window to use

Why Documentation Matters to Auditors

Under AU-C Section 540, auditors are required to evaluate whether "significant assumptions used by management are reasonable." When management relies on a valuation specialist, the auditor evaluates the specialist's work — including the judgments underlying it.

An undocumented judgment is, from the auditor's perspective, an unsupported judgment. And an unsupported judgment is an audit finding waiting to happen.

The professional judgment documentation Format

A well-structured professional judgment documentation captures four elements for each decision:

1. The Decision

What was decided. "We applied a 5% company-specific risk premium to the WACC."

2. Alternatives Considered

What other options were evaluated. "We considered 3%, 5%, and 7% based on comparable stage companies."

3. The Rationale

Why this option was selected. "5% reflects the company's stage, limited customer concentration, and positive revenue growth trajectory."

4. Supporting Evidence

Data or references supporting the choice. "Consistent with BVR CSRP Survey data for Series B SaaS companies with 50-100% YoY growth."

The 15 Judgment Decisions in Every 409A

# Decision Audit Risk
1 Valuation approach selection Medium
2 Approach weighting High
3 Comparable company set High
4 Multiple selection Medium
5 Discount rate / WACC components High
6 Company-specific risk premium Very High
7 Revenue/financial projections used High
8 Equity allocation method (OPM/Backsolve/PWERM) High
9 Volatility peer set Medium
10 Time to liquidity assumption Medium
11 DLOM methodology selection Very High
12 DLOM magnitude Very High
13 Scenario probabilities (if PWERM) Very High
14 Treatment of recent transactions High
15 Reconciliation of approaches Medium

What "Good" Looks Like

✅ Well-Documented Judgment

"We selected a 25% DLOM using the Finnerty put option model. Inputs: 60% volatility (median of 8 comparable public companies — see Appendix C), 3-year estimated time to liquidity (consistent with management's Series C fundraising timeline and 2028 target exit). This result is consistent with the 20-30% range observed in FMV Opinions restricted stock studies for companies with similar holding periods. We considered the Chaffe model but Finnerty is more appropriate here because it models an average-price put rather than a point-in-time put, better reflecting the continuous nature of the marketability restriction."

❌ Poorly Documented Judgment

"We applied a 25% DLOM based on restricted stock studies and quantitative methods."

Which studies? Which methods? What inputs? Why 25% and not 20% or 30%? This documentation will generate supplemental requests.

FairValueX Judgment Documentation

the professional judgment register is our Professional judgment documentation register — a structured record of every material decision with alternatives considered, rationale, and supporting evidence. This is one of the key reasons auditors trust our deliverables: every judgment is pre-documented, not reconstructed after the fact.

Related Resources

Every judgment in our deliverables is documented.

FairValueX maintains a Professional judgment documentation register in every binder — mapping each assumption to the reasoning, source, and alternative considered.

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