Due Diligence
DD · Commercial Due Diligence · Legal Due Diligence
Due diligence is a structured investigation of a business, asset, or contract before a transaction — typically an acquisition, investment, major partnership, or large contract. It identifies risks, confirms representations, and helps price the deal. Legal DD focuses on contracts, litigation, IP, employment, and compliance.
What due diligence actually does
Due diligence turns assumptions into evidence. Before signing an acquisition, investment, or major partnership, the buyer needs to know what they are actually buying: does the target own its IP, are the customer contracts transferable, is there pending litigation, do the employment contracts have non-competes, is the company compliant with data protection law. A typical legal DD workflow involves a data room with hundreds to thousands of documents, a structured request list mapping to risk areas, tabular review extracting key terms across the contract portfolio, and a disclosure schedule documenting what was reviewed and what issues were found. The output is a DD report that feeds directly into deal pricing, indemnity negotiations, and closing conditions.
Why it matters
The issues you miss in due diligence become the issues you live with after closing. A missed change-of-control provision in a key vendor contract can mean the acquired business loses a major supplier the day after close. An overlooked non-compete can prevent a key employee from joining the acquirer. An unnoticed pending regulatory action can wipe out the deal thesis. The entire purpose of DD is to find these issues before signing, when the price can still be adjusted or the deal walked away from. Post-close, the only remedy is indemnification — and as the indemnification entry notes, that is where contracts allocate the largest dollar risks.
Common pitfalls
- 1.Request list is generic — not tailored to the actual target, so material issues outside the default categories get missed.
- 2.Reviewers work in silos — legal, financial, and commercial DD teams that do not share findings miss cross-cutting issues.
- 3.Tabular review is manual and inconsistent — fatigue at contract 400 produces different scoring than at contract 40.
- 4.Findings are not ranked by materiality — the DD report lists 500 items without differentiating deal-breakers from housekeeping.
- 5.Disclosure schedule is drafted loosely — vague language creates post-close disputes about what was actually disclosed.
Frequently asked questions
- How long does legal due diligence typically take?
- For a mid-market transaction, 3 to 6 weeks of active review is typical. Larger deals run 2 to 4 months. AI-assisted DD compresses the first-pass review substantially — tabular review that took weeks can now run in hours — but human review of findings and negotiation of issues still takes time.
- What is the difference between buy-side and sell-side DD?
- Buy-side DD is the buyer investigating the target. Sell-side DD is the seller preparing a vendor due diligence report in advance, which is shared with potential buyers. Sell-side DD reduces deal friction and helps maintain competitive tension across multiple bidders.
- Can AI replace a DD lawyer?
- Not for judgment calls, but AI does the mechanical work better. Tabular review of 2,000 contracts, risk flagging against a standard clause library, extraction of key terms — these are the repetitive tasks AI handles well. Lawyers keep judgment over materiality, strategy, and negotiation.
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