Corporate Restructuring, Valuation and Insolvency · Process of M&A Transactions

Due Diligence in Mergers and Acquisitions: Types and Procedure

Updated 11 October 2026 · Fact-checked

Due diligence in M&A is a structured investigation of a target company before the deal closes. The buyer checks financial, legal, tax and commercial facts to confirm value, find liabilities and decide price, warranties and conditions. In an exam answer, state the type, scope, procedure, red flags found and their effect on the deal.

Understand Due Diligence in M&A

Due diligence is the buyer's fact check on the target. The seller tells you the business is sound. Due diligence tests that claim against documents, records and market evidence before you sign or close.

It matters because the buyer usually takes over the target's history along with its assets. In a share acquisition or a merger, hidden debts, pending cases, tax demands and defective contracts become the buyer's problem. A good review finds them early, so you can lower the price, ask for indemnities, add conditions or walk away.

The four main types are these:

Financial due diligence: checks quality of earnings, assets, liabilities, working capital, debt, contingent liabilities and the reliability of financial statements.
Legal due diligence: checks title to assets, incorporation and statutory records, contracts, litigation, licences, charges and compliance with the Companies Act and other laws.
Tax due diligence: checks tax filings, assessments, disputes, exposures, and the tax effect of the deal structure.
Commercial due diligence: checks market position, customers, competitors, growth prospects and the business plan.

Other reviews are often added: operational, HR and labour, environmental, IT and cyber, and intellectual property. Pick them by the target's business.

The key contrast students are asked about: financial due diligence asks whether the numbers are reliable and what the business is worth. Legal due diligence asks whether the target legally owns what it claims and what legal obligations or risks sit behind it.

Due diligence is not a single event. It starts after a non-binding term sheet or MOU, usually under a confidentiality agreement, and runs until signing. Findings feed into the valuation, the purchase agreement, representations and warranties, indemnities and conditions precedent.

Key rules to remember

Purpose of due diligence: Verify facts + identify risks + adjust price and terms; Use this as the one-line frame for any answer.
Four main types: Financial + Legal + Tax + Commercial; Add operational, HR, environmental, IT and IP reviews only if the facts suggest them.
Financial vs legal: Financial = reliability of numbers and value; Legal = ownership, validity and liabilities; This is the usual comparison question.
Outcome of findings: Red flag → price cut, indemnity, warranty, condition precedent or exit; Always link each finding to a deal response.

How to solve Due Diligence in M&A questions

Use this method for any question on due diligence, whether it asks for types, scope, procedure or a case-based advice.

1Define due diligence in one line: a pre-deal investigation of the target to verify facts and find risks.
2Identify the deal type (share purchase, merger, business transfer) and the target's industry from the facts.
3Name the relevant types of due diligence and state the scope of each, with the documents you would check.
4Give the procedure in order: confidentiality agreement, request list, data room, review, management meetings, report.
5Apply the facts: spot each red flag, such as pending litigation, unregistered charges, delayed filings or tax disputes, and say which type finds it.
6Conclude with the deal response: price adjustment, indemnity, warranty, condition precedent, or withdrawal.
7Add a drafting or compliance point, such as the report format or checking statutory registers and filings with the Registrar.

Quickest way: Type, scope, red flag, response

When to use it: Use when you have limited time or the question is a short note or a difference question.

Write the definition in one sentence.
List the four types with one line of scope each.
For a difference question, draw two columns in your answer: focus, documents checked, who does it, outcome.
Close with one line on how findings change price and contract terms.

Common mistakes in Due Diligence in M&A

Treating due diligence as only a financial audit.
Students link the word diligence with accounts and numbers.
Fix: Always cover legal, tax and commercial reviews as well, and say which risks each one finds.
Mixing up financial and legal due diligence.
Both look at liabilities, so the lines blur.
Fix: Financial checks amounts and quality of earnings. Legal checks title, validity of contracts, litigation and compliance.
Listing documents without a conclusion.
Students memorise checklists and stop there.
Fix: End every point with what the buyer does about the finding: renegotiate, protect by contract, or exit.
Ignoring the procedure and timing.
Students treat due diligence as a single report.
Fix: Show the sequence: confidentiality, request list, data room review, management discussions, report, then negotiation of the agreement.
Quoting section numbers for due diligence that do not exist.
Case-based papers push students to cite a section for everything.
Fix: Due diligence is a commercial practice, not a single statutory process. Cite sections only for the specific compliance you are checking, and only if you are sure of them.

Worked examples

Example 1

Explain the types of due diligence a buyer should carry out before acquiring all the shares of a manufacturing company, and say what each would check.

Show the solution

Define: due diligence is a pre-deal investigation of the target to verify facts and identify risks.
Financial: audited statements, quality of earnings, working capital, borrowings, contingent liabilities and inventory.
Legal: incorporation documents, statutory registers, title to land and plant, charges, contracts, licences and pending litigation.
Tax: returns, assessments, disputes and tax exposure, plus the tax effect of the purchase structure.
Commercial: customers, competitors, market share, demand outlook and the business plan.
Add as needed: environmental and labour reviews, because the target is a manufacturer.
Conclude: the findings are used to set price, warranties, indemnities and conditions precedent.

Answer: The buyer should carry out financial, legal, tax and commercial due diligence, with environmental and labour reviews added for a manufacturer. Each checks a different risk, and together they decide price and contract protections.

Example 2

Asha Textiles Ltd is buying 100% shares of Meru Dyes Pvt Ltd. Legal due diligence shows a pending customs dispute, a factory mortgage not disclosed to the buyer, and a key supply contract that ends if control changes. Advise Asha Textiles.

Show the solution

Identify the type: these are legal due diligence findings.
Customs dispute: this is a contingent liability. Ask for the amount at stake, seek a price reduction or an escrow, and obtain a specific indemnity from the sellers.
Undisclosed mortgage: check the charge records of the target, and ask the sellers to explain why it was not disclosed. Make release of the charge, or lender consent, a condition precedent to closing.
Change-of-control clause: the supply contract can be lost on the deal. Get the counterparty's written consent before closing, or reflect the risk in price.
Reassess: if the sellers do not cooperate or the risks are material, Asha Textiles may renegotiate or withdraw.
Document: record the findings in the due diligence report and carry the protections into the share purchase agreement as warranties, indemnities and conditions.

Answer: Asha Textiles should treat the three findings as red flags. It should seek price protection or an indemnity for the customs dispute, make clearing the mortgage a condition precedent, and obtain the counterparty's consent for the supply contract. It should withdraw if the risks remain unresolved.

Exam tips

For a difference question, compare focus, documents checked and outcome. A short point-wise comparison scores better than long paragraphs.
In case-based questions, name each red flag, say which type of due diligence finds it, and state the deal response.
Do not invent a statutory section for due diligence. Cite a section only where you are checking a specific compliance and are certain of it.
Mention the confidentiality agreement and data room in procedure answers. Examiners look for the sequence.
Finish with the link to price, warranties and conditions precedent.

Practice questions from Process of M&A Transactions

Due Diligence in M&A in other exams

The same ground in other exams, if you are preparing for more than one or want another angle on it.

Due Diligence in M&A: frequently asked questions

What are the types of due diligence in M&A?

The main types are financial, legal, tax and commercial due diligence. Operational, HR, environmental, IT and intellectual property reviews are added when the target's business needs them.

What is the difference between financial and legal due diligence?

Financial due diligence tests the reliability of the numbers, the quality of earnings and the value of the business. Legal due diligence tests title to assets, validity of contracts, litigation and compliance with law.

How is legal due diligence on an acquisition conducted?

The buyer signs a confidentiality agreement and sends a request list. Advisers review the data room documents such as constitutional documents, registers, contracts, charges, licences and litigation records, meet management, and prepare a report listing red flags and recommendations.

Is due diligence mandatory under the Companies Act, 2013?

The Act does not lay down due diligence as a single mandatory step for deals. It is a standard commercial practice, but the buyer's board is expected to act with care, and the findings are used to check compliance and protect the buyer.