VDD (vendor due diligence) is diligence run on behalf of the seller before a transaction — packaged so multiple buyers can review the same verified facts.

How it works

In a broad auction or competitive process, the company (or its shareholders) hires banks or consultants to produce vendor due diligence — often split into:

• Financial VDD: quality of earnings, working capital, debt-like items
• Commercial VDD: market size, customer concentration, competitive position
• Legal VDD: corporate structure, IP, material contracts (sometimes separate)

The report lives in a data room. Buyers receive reliance letters allowing them to trust the work within defined limits. They still perform confirmatory diligence — customer calls, IT review, management meetings — but start further along the learning curve.

Cost sits with the seller, typically six figures for mid-market deals. Timeline adds weeks upfront but can shave months off a multi-bidder process by parallelizing buyer work.

Venture-backed exits use VDD less often at early stages; it is more common in growth equity recapitalizations and PE-led sales above meaningful revenue thresholds.

Why it matters

• Founders: A clean VDD reduces last-minute price chips tied to “new findings.” Weak VDD that glosses over customer churn or accounting quirks destroys credibility fast.
• Investors: Sponsors expect VDD in competitive sales. For board members, approving spend means weighing process speed against revealing sensitive data to advisors before a deal is certain.

Common mistake

Treating VDD as a marketing document. Buyers treat inconsistencies between VDD and management answers as red flags — and re-trade aggressively.

Related ideas

See also CDD (commercial due diligence), quality of earnings, and data room management.