Due Diligence
The comprehensive investigation that turns assumptions into verified facts before committing capital
~25 min read
Due diligence is the systematic investigation of a target company that occurs after an LOI is signed and exclusivity is granted. It is the process of converting assumptions into verified facts before committing hundreds of millions of dollars of capital. If the CIM and management presentations are the seller's pitch, due diligence is the buyer's audit.
A typical PE due diligence process takes 45-90 days, involves multiple third-party advisors (accounting firms, law firms, consultants, industry experts), and costs $1M-$5M+ in professional fees for a mid-to-large buyout. Despite this cost, thorough diligence is cheap insurance: a single missed issue can destroy an entire investment. The diligence process runs across multiple workstreams simultaneously, each managed by a different team and set of advisors.
Due Diligence Workstreams: Parallel Tracks
Financial due diligence
Led by a Big Four or national accounting firm. Focuses on the Quality of Earnings (QoE) analysis, which validates adjusted EBITDA, working capital trends, debt-like items, and the sustainability of historical earnings. This is the most critical workstream because it directly impacts the purchase price.
Commercial due diligence
Often led by a strategy consulting firm. Assesses market size, growth trends, competitive dynamics, customer satisfaction, and the credibility of the company's growth plan. Includes customer interviews, competitor analysis, and independent market research.
Operational due diligence
Evaluates the company's technology infrastructure, IT systems, cybersecurity posture, manufacturing processes, supply chain resilience, and operational scalability. Identifies risks and improvement opportunities that will inform the value creation plan.
Legal due diligence
Led by the buyer's law firm. Reviews all material contracts, pending and threatened litigation, intellectual property ownership, environmental liabilities, employment agreements, regulatory compliance, and corporate governance. Findings directly shape the reps and warranties in the purchase agreement.
Management due diligence
Assesses the leadership team's capability, track record, and fit with the PE firm's operating model. Includes extended interviews, background checks, reference calls, and psychometric assessments. The goal is to determine which executives to retain, which to replace, and where to recruit new talent.
Financial due diligence
Led by a Big Four or national accounting firm. Focuses on the Quality of Earnings (QoE) analysis, which validates adjusted EBITDA, working capital trends, debt-like items, and the sustainability of historical earnings. This is the most critical workstream because it directly impacts the purchase price.
Commercial due diligence
Often led by a strategy consulting firm. Assesses market size, growth trends, competitive dynamics, customer satisfaction, and the credibility of the company's growth plan. Includes customer interviews, competitor analysis, and independent market research.
Operational due diligence
Evaluates the company's technology infrastructure, IT systems, cybersecurity posture, manufacturing processes, supply chain resilience, and operational scalability. Identifies risks and improvement opportunities that will inform the value creation plan.
Legal due diligence
Led by the buyer's law firm. Reviews all material contracts, pending and threatened litigation, intellectual property ownership, environmental liabilities, employment agreements, regulatory compliance, and corporate governance. Findings directly shape the reps and warranties in the purchase agreement.
Management due diligence
Assesses the leadership team's capability, track record, and fit with the PE firm's operating model. Includes extended interviews, background checks, reference calls, and psychometric assessments. The goal is to determine which executives to retain, which to replace, and where to recruit new talent.
Financial Due Diligence and Quality of Earnings
The Quality of Earnings (QoE) report is the cornerstone of financial due diligence. Prepared by an independent accounting firm hired by the buyer, the QoE validates (or challenges) the adjusted EBITDA presented in the CIM. Key components include:
- Adjusted EBITDA validation. The accounting firm independently recalculates EBITDA from the general ledger, testing every add-back for legitimacy. Aggressive add-backs are reversed, reducing the earnings figure that the buyer is willing to pay a multiple on.
- Revenue quality analysis. Examines whether revenue is recurring vs. one-time, contractual vs. at-will, growing vs. declining by customer cohort, and whether any revenue was pulled forward from future periods.
- Working capital analysis. Calculates the normalized level of net working capital (current assets minus current liabilities) required to run the business. This 'peg' is critical because the purchase agreement will include a mechanism to adjust the price up or down based on actual working capital at closing.
- Debt-like items. Identifies obligations that function like debt but may not appear on the balance sheet: deferred revenue, unfunded pension liabilities, capital lease obligations, outstanding litigation reserves, and unpaid taxes.
- CapEx analysis. Distinguishes maintenance CapEx (required to sustain current operations) from growth CapEx (investment in expansion). Maintenance CapEx is effectively a reduction in free cash flow and impacts the true earnings power of the business.
The QoE frequently reduces the seller's adjusted EBITDA by 10-20%. On a deal valued at 10x EBITDA, a $2M reduction in EBITDA translates to a $20M reduction in enterprise value. This is why the QoE is the highest-impact deliverable in the entire diligence process.
Commercial Due Diligence: Validating the Growth Story
Commercial due diligence tests whether the market opportunity and competitive position described in the CIM are real. This workstream is especially important for growth-oriented investments where the buyer is paying a premium multiple based on future potential. Key activities include:
- Market sizing. Independent assessment of the total addressable market (TAM) and serviceable addressable market (SAM). Is the market as large as the CIM claims? Is it growing at the stated rate?
- Customer interviews. Confidential calls with the company's top 10-20 customers to assess satisfaction, switching risk, willingness to expand the relationship, and perception of competitive alternatives. These interviews often reveal risks that never appear in the CIM.
- Competitive positioning. Mapping the competitive landscape to understand the company's moat (or lack thereof). How defensible is the company's market share? Are there emerging competitors or technology shifts that could disrupt the business?
- Pricing power. Can the company raise prices without losing customers? Pricing power is one of the strongest indicators of a durable competitive advantage and a key driver of margin expansion under PE ownership.
- Sales pipeline validation. For companies with a significant pipeline of pending contracts or proposals, the consultant verifies the probability-weighted value and expected close timing.
A well-executed commercial DD report either gives the buyer confidence to proceed at the agreed price, identifies risks that justify a price reduction, or uncovers issues severe enough to kill the deal entirely.
Operational Due Diligence
Operational DD evaluates the infrastructure that keeps the business running. For technology companies, this means assessing code quality, technical debt, scalability of the architecture, cybersecurity vulnerabilities, and the IT team's capabilities. For manufacturing companies, it covers plant condition, equipment age, capacity utilization, and supply chain concentration. The output is a list of operational risks and a prioritized set of improvement opportunities that feed into the post-acquisition value creation plan.
Legal Due Diligence
The buyer's law firm conducts a comprehensive review of the company's legal exposures. This includes reading every material contract (customer agreements, supplier agreements, leases, employment contracts), identifying change-of-control provisions that could be triggered by the acquisition, reviewing all pending or threatened litigation, confirming intellectual property ownership and freedom to operate, assessing environmental liabilities (especially for manufacturing or real estate-heavy businesses), and verifying compliance with applicable regulations. Legal findings directly inform the reps and warranties that the seller will make in the purchase agreement.
Management Due Diligence
Beyond the initial management presentation, the PE firm conducts deeper assessment during the diligence period. This includes one-on-one interviews with each senior executive, 360-degree reference calls with former colleagues and board members, and sometimes psychometric or leadership assessments administered by an executive assessment firm. The goal is to build a clear picture of who stays, who goes, and where new talent needs to be recruited. Many PE firms consider management quality the single most important factor in investment success.
The 100-Day Plan: From Diligence to Action
During due diligence, the PE firm begins formulating the 100-day plan: a detailed operational roadmap for the first 100 days after closing. The plan is built from findings across all diligence workstreams and typically covers:
- Quick wins. Immediate actions that generate visible results: pricing adjustments, cost reductions, working capital improvements, renegotiation of supplier contracts.
- Organizational changes. New hires, role changes, and management upgrades identified during management DD.
- Systems and infrastructure. IT upgrades, ERP implementations, or cybersecurity improvements flagged during operational DD.
- Strategic initiatives. Add-on acquisition pipeline, geographic expansion, new product launches, or sales force expansion informed by commercial DD.
- Financial infrastructure. Upgrading reporting, implementing monthly board reporting packages, establishing KPI dashboards, and installing a PE-grade CFO if needed.
- Governance. Establishing the board of directors, setting meeting cadence, defining decision rights between the PE firm and management.
The 100-day plan ensures that the transition from due diligence to ownership is seamless and that value creation begins on day one. Firms that wait until after closing to start planning typically lose 3-6 months of momentum, which can meaningfully impact returns over a 4-5 year hold period.
Due Diligence in Action: When the QoE Reshapes a Deal
A PE firm signs an LOI to acquire a healthcare staffing company at $200M enterprise value (10x the seller's adjusted EBITDA of $20M). During financial due diligence, the QoE report reveals several issues:
- The seller added back $1.5M for 'one-time recruiting costs,' but the firm has incurred similar costs in each of the past four years. The QoE reverses this add-back.
- $2M of revenue was pulled forward from Q1 of the following year through aggressive recognition of contracts not yet started.
- Net working capital is $3M higher than the seller's stated peg, meaning the buyer would need to fund additional working capital at closing.
The QoE concludes that sustainable EBITDA is $17.5M, not $20M. At the same 10x multiple, the enterprise value drops to $175M. The PE firm presents these findings to the seller and renegotiates the price from $200M to $180M (reflecting a small premium for the seller's cooperation in resolving the issues). The seller accepts rather than re-starting the auction process. This $20M savings covers the entire cost of diligence many times over and illustrates why financial DD is the highest-ROI activity in the deal process.
Composite example based on common QoE findings in healthcare services
Quiz: Due Diligence
6 questions · ~3 min