What vendor due diligence is and why the seller should do it first
Vendor due diligence is corporate due diligence commissioned and funded by the seller, carried out by independent advisors before the company is presented to the market or to a specific buyer.
The result is a structured report—the vendor due diligence report (also known as an information memorandum)—which the seller can share with potential buyers, typically under a non-disclosure agreement and a reliance letter that extends its usability to them as well.
As well as providing a transparent picture of the company’s economic and financial health, its strengths and its development plan, the aim is not to hide critical issues, but to identify and address them before buyers discover them during negotiations, when the bargaining leverage is already in their favour.
A company that comes to the table with a completed vendor due diligence conveys greater transparency and reduces the risk of repeated requests, stop-and-go delays and downward price renegotiations.
In summary
Vendor due diligence is a corporate due diligence process commissioned by the seller—prior to the involvement of any potential buyer—to independently assess the company’s financial, legal, and operational status. In M&A transactions, it allows for the early identification and resolution of critical issues, helps accelerate negotiations, and strengthens the seller’s bargaining position.
When an entrepreneur decides to initiate the sale of their company, a business unit, or a block of shares, the most delicate moment is almost never the price negotiation, but rather the verification phase that precedes it. This is where due diligence comes into play: the set of economic-financial, legal, and operational analyses through which the buyer assesses what they are actually purchasing.
The problem for the seller is that this analysis is often conducted by the counterparty, according to a timeline and criteria beyond the seller’s control; furthermore, critical issues not previously addressed may surface during negotiations, thereby weakening the seller’s bargaining position. Vendor due diligence is designed precisely to reverse this dynamic.
Vendor due diligence vs the buyer’s corporate due diligence: the differences
Corporate due diligence, in its most common sense, is carried out by the buyer and its advisors after a letter of intent (LOI) is signed, with the aim of verifying the soundness of the investment and identifying factors that may affect the price, the contractual warranties or even the decision to proceed. It is a typically adversarial analysis, conducted exclusively in the buyer’s interest.
- Vendor due diligence: initiated and controlled by the seller; preventive and preparatory purpose; shared with several potential buyers
- Buyer due diligence: initiated by the purchaser; verification and protection purpose; use reserved to the buyer and its advisors
The two activities are not alternatives, but complementary: a well-conducted vendor due diligence does not eliminate the buyer’s due diligence; it makes it faster and smoother, because it reduces the avoidable areas of uncertainty — unreconciled figures, untraceable contracts, out-of-date authorisations — that generate repeated requests and slow down the closing of the deal.
Vendor due diligence in M&A transactions: phases and areas of analysis
A complete vendor due diligence, supporting an M&A due diligence process, typically covers three macro-areas of analysis, carried out in parallel by specialist teams:
- Economic-financial area
- Quality of earnings analysis, reconciliation of financial statement data, normalisation of any extraordinary or non-recurring items, verification of the net financial position and of working capital.
- Commercial and operational area analysis
- Analysis of the forward-looking business plan (industrial, development, relaunch or restructuring plan, depending on the case)
- Legal, tax and compliance area
Verification of key contracts, pending litigation, ownership of assets and intellectual property, the adequacy of the organisational models under Legislative Decree 231/2001, and the correct handling of personal data when setting up the data room under EU Regulation 2016/679 (GDPR) are some of the main key points.
In transactions with foreign investors in strategic sectors, it must also be checked whether the Golden Power regime applies (Decree-Law 21/2012, as most recently amended by Law 4/2026), which may require prior notification to the Presidency of the Council of Ministers.
When and for whom a vendor due diligence makes sense
Vendor due diligence is particularly advisable when the sale involves several potential buyers in parallel (competitive processes), when the company has a complex corporate or accounting structure, or when the seller wants to keep to a minimum the exclusivity periods granted after the letter of intent is signed.
It is a tool used mainly by medium-sized and large companies and corporate groups, but increasingly requested also by SMEs approaching an extraordinary finance process for the first time.
A recurring case
A manufacturing company in Northern Italy, in the process of selling a business unit to an industrial group, commissioned a vendor due diligence before opening contacts with potential buyers. Theanalysis brought to light certain supply contracts lacking updated transfer clauses, which were then remedied before negotiations began.
The dossier prepared in this way made it possible to share an already-verified information set with several interested parties in parallel, shortening the negotiation phase. The case, reported anonymously, is representative of the situations SBG Service frequently encounters when supporting companies through sale processes.
How SBG Service supports companies in due diligence
SBG Service is the Self Business Group division dedicated to due diligence and valuation of real-estate, financial and credit assets, with a team of experts in legal, tax and KYC analysis. In the field of vendor due diligence, SBG Service supports companies with:
- Preparation of the vendor due diligence report on an economic-financial, legal and operational basis
- Organisation of the data room and of the information set for potential buyers
- Valuation of real-estate, financial and credit assets relevant to the transaction
- Coordination with SBG Consulting on extraordinary finance aspects and deal negotiation
Before initiating sale negotiations, verify the strength of your company through an independent due diligence process.
Obtain Due Diligence with SBG SERVICE
Frequently asked questions
What is vendor due diligence?
It is corporate due diligence commissioned by the seller, before potential buyers come on the scene, to independently verify the company’s economic-financial, legal and operational situation and share a structured report with the parties interested in the sale.
How does it differ from the buyer’s corporate due diligence?
Vendor due diligence is initiated and controlled by the seller for preparatory purposes, while the buyer’s due diligence is carried out by the purchaser after the letter of intent, to verify and protect its own interests. They are complementary, not alternatives.
Which areas does an M&A due diligence cover?
Typically three macro-areas: economic-financial (financial statement data, cash flow, net financial position, business plan), legal-tax-compliance (contracts, litigation, the 231 organisational model, GDPR, Golden Power where relevant) and commercial-operational (customer portfolio, business continuity).
How long does a vendor due diligence take?
Timings vary according to the size and complexity of the company and of the areas analysed; in any event, it is an activity to start well in advance of opening negotiations, so that the issues identified can be resolved before engaging with buyers.
Who should consider a vendor due diligence?
It is particularly suitable for well-structured SMEs and corporate groups launching competitive sale processes with several potential buyers, or wanting to shorten the exclusivity periods following the letter of intent.