The First 100 Days After an M&A Deal: A Legal Integration Checklist for Start-ups and Investors

24.04.2026

The main focus in M&A transactions, for both start-ups and investors, is traditionally on conducting due diligence, agreeing the terms, signing the documents and completion. Completion is often perceived as the culmination: the agreement has been signed, the money has been transferred, and both teams go off to drink champagne.

However, it is precisely at this point that a new, and often no less complex, stage of legal and operational integration of the business begins.

As our practical experience shows, the first 100 days after completion largely determine how the company will develop further. In this article, we analyse the typical issues faced by founders and investors immediately after completion of a transaction and provide a practical checklist for closing the key legal tasks of the first 100 days.

1. The gap between the transaction documents and the company’s actual operations

Why does the gap arise?

After completion, the company faces several structural changes at the same time: new shareholders with legally documented rights appear, a new corporate governance system is introduced or the existing one changes, and additional restrictions on decision-making arise. At the same time, the team continues to operate under the previous operational processes – with the same suppliers, the same approval timelines and unchanged internal procedures.

The gap arises when the transaction documents have already changed the rules for managing the company, but the internal business processes have not yet changed. It creates risks that are not operational but specifically legal in nature: decisions taken without complying with the new corporate procedures may be challenged by shareholders, and breach of post-completion obligations may trigger the investor protection mechanisms provided for in the transaction

How to take updated reserved matters into account

Such mechanisms include, first and foremost, reserved matters – a list of decisions that cannot be made by the board of directors or management without prior approval from the shareholders (as a rule, investor approval is mandatory).

Reserved matters protect investors against the majority shareholders unilaterally changing the direction of the company’s business after completion. The list of such matters generally covers:

• Structural changes:
  amendments to the company’s articles of association; any amendment that may affect shareholders’ rights or the company’s structure; an increase or decrease in share capital; changes to the company’s principal areas of business; the creation of, and participation in, subsidiaries; reorganisation or liquidation of the company, and other matters;
• Corporate decisions:
  the issue of new shares; the issue of new shares or other securities that may dilute existing shareholders’ interests; changes to shareholder rights: any changes to the rights or privileges of shareholders that may affect their investment; share transfers: restrictions on the sale or transfer of shares, especially where there is a change of control over the company;
• Financial decisions:
  profit distribution; decisions on the payment of dividends or other forms of capital distribution; budget and major expenditure: approval of the annual budget and major capital expenditure; raising additional investment or financing, including convertible loans, SAFEs and other forms of investment or financing;
• Management decisions and control:
  changes to the composition of the board of directors; appointment, replacement or removal of directors; directors’ rights and duties: changes to directors’ powers and duties, as well as the terms of their contracts; key appointments: appointment or dismissal of key employees, such as the CEO, CFO and other senior executives; allocation of an option pool and, more generally, creation of an incentive programme that entails dilution of the investor’s shareholding;
• Operational decisions:
  material transactions; entry into or termination of material transactions that fall outside the company’s ordinary course of business; credit obligations: raising loans, issuing bonds or granting substantial pledges and guarantees; transactions involving IP and/or real estate (depending on the company’s product).

Making decisions that fall within reserved matters without following the approval procedure creates a risk that those decisions will be challenged and may give rise to conflict with investors. For reserved matters to operate properly, they must be set out in a shareholders’ agreement, the articles of association and/or a separate investment agreement (Investment Agreement or Investors’ Rights Agreement) that is legally binding on the company.

2. Post-completion obligations: obligations that continue after the transaction

What constitutes post-completion obligations

In many investment and M&A transactions, some obligations relate to the period after completion – either because of their procedural complexity or so that they do not become conditions preventing completion itself.

Such obligations (post-completion covenants) are traditionally set out in the share purchase agreement, share subscription agreement or other binding documents as obligations that the parties must perform within a certain period after completion of the transaction.

Typical post-completion obligations include:

• registration of corporate changes in the relevant registers, such as Companies House in the UK, ACRA in Singapore and the Department of Registrar of Companies and Intellectual Property in Cyprus;
• appointment of a new board of directors;
• changes to the powers of directors and bank signatories;
• implementation of procedures for agreeing decisions with investors (including reserved matters);
• performance of specific conditions of the investment agreement (for example, transfer of IP rights, implementation of option programmes), etc.

Consequences of failing to perform post-completion obligations

Late or improper performance of post-completion obligations entails serious consequences:

1. if the company breaches terms recorded in the transaction documents, the investor obtains the right to apply contractual protection mechanisms;
2. corporate disputes arise between shareholders, which may result in a decision-making deadlock for the company and even litigation;
3. unresolved post-completion matters will surface at the next investment round: any serious investor will identify them during due diligence.

Updating the composition of the governing bodies

One of the key post-completion obligations is to bring the composition of the board of directors into line with the terms of the transaction. Venture investors generally require one or more board seats as a condition of their investment. Sometimes investors who do not wish to participate directly in management appoint an observer, who has the right to attend meetings of the governing bodies and remain informed of all decisions being taken.

Changes to the composition of the board require formal approval by the shareholders and by the board itself in accordance with the rules set out in the constitutional documents.

3. Contractual risks after a change of control

Change of control clause and when it is triggered

A change of control clause is a contractual provision that is automatically triggered when control over one of the parties passes to a new person.

Typical triggers for such a provision include:

1. transfer of more than 50% of the shares or interests to a new owner;
2. sale of a substantial part of the company’s assets;
3. merger or accession.

After an M&A transaction, such provisions may require the counterparty to be notified, provide for the need to obtain its consent, or give it the right to terminate the contract. The exact set of consequences depends on the wording of each particular contract – which is why a full audit of commercial contracts, even if partially carried out at the legal due diligence stage, should also be completed at the post-completion stage.

Consequences of failing to comply with change of control terms

1. Right to terminate: the counterparty unilaterally terminates the contractual relationship, which is particularly critical for agreements with key clients, suppliers and licence agreements;
2. Right to renegotiate terms: the counterparty initiates negotiations to change the price or scope of obligations;
3. Mandatory notification: breach of notification deadlines may itself become grounds for termination.

It should also be noted that, in asset deals, each contract requires individual re-execution or novation, whereas in share deals the contracts formally remain with the same company – however, a change of control clause may still be triggered.

Audit of the contract portfolio

 

To reduce risks, it is recommended that, in the first weeks after completion, the company should:

• prepare a register of all current contracts indicating the presence or absence of a change of control clause;
• classify contracts by level of criticality (key clients, licences, partnership agreements);
• determine which contracts require notification and which require the counterparty’s consent;
• set deadlines and appoint responsible persons for notifying counterparties and updating contractual terms;
• conduct negotiations with counterparties where necessary.

4. Investor information rights and the reporting system

How information rights operate

Investors almost always provide for extensive information rights for themselves, which are expressed as specific obligations of the start-up to provide financial and operational information about the company’s activities according to an agreed schedule. As a rule, such rights are set out in the shareholders’ agreement and sometimes in an investors’ rights agreement.

The standard package of information rights includes an obligation to provide:

• annual audited accounts – within 90-120 days after the end of the financial year;
• quarterly unaudited accounts – within 30-45 days after the end of the quarter;
• annual budget – for example, within 30 days from the start of the financial year.

After completion, the company must immediately build processes to perform these obligations: establish financial reporting, appoint persons responsible for preparing and distributing information, and distinguish between information provided to all investors and information provided only to board members.

5. Team integration and launch of an ESOP

Why launch an ESOP after the transaction

An ESOP (Employee Stock Option Plan) is an option programme for employees that allows them to acquire shares or interests in the company at a pre-agreed price after completion of the vesting period.

In the context of M&A transactions, an ESOP solves several tasks at once: it retains key employees during the integration period, aligns the team’s interests with those of the shareholders, and makes the company more attractive to future investors.

In venture transaction practice, where a company is acquired, options are generally converted or bought out, and a new retention programme is introduced for key employees. This mechanism should be provided for in the transaction documents in advance.

The most costly mistakes in implementing an ESOP

Mistakes in implementing or updating an ESOP after the transaction may have serious consequences:

1. Unpredictable dilution: each issue of new shares for an ESOP reduces the percentage interests of existing shareholders, including investors. If the ESOP issue exceeds the approved pool, this is a breach of reserved matters; such an issue may be challenged and cancelled;
2. Conflicts between shareholders: disagreements over the size of the pool, vesting and methodology may become a source of corporate disputes;
3. Problems at the next round: a new investor will certainly check the cap table and the history of option issuances during due diligence. Irregularities in the formalisation of the ESOP are almost a guaranteed discount to the company’s valuation.

Usually, for companies at early stages of development, the ESOP pool may be 15% or more; at later stages (Seed, Series A), it is typically around 10%; and for more mature rounds (Series B+), 5-8%.

To minimise risks, we recommend agreeing in advance with investors, before each round, both the percentage of shares reserved for the ESOP and the methodology for issuing new shares.

6. Practical legal checklist for the first 100 days

Below is a structured post-M&A integration checklist, divided into three time periods. Use it as a working tool: appoint responsible persons, set deadlines and mark completed items.

First 14 days: urgent measures

Days 15-60: corporate and contract management

Days 61-100: operational synchronisation

 

Conclusion

An M&A transaction is not a final point, but the beginning of a new phase of business development. It is during the first months after completion that the agreements between investors and founders are put into practice, a new corporate governance system is built, and the legal foundation for further growth is formed.

This means three parallel tracks. The first is immediate performance of post-completion obligations – corporate registration, formation of the board of directors and updating of powers. The second is a contract audit and work with change of control risks. The third is building a corporate governance system for the new realities: reserved matters, ESOP and investor reporting.

Companies that address these issues immediately significantly reduce legal risks and arrive at the next round without “loose ends”. In international transactions involving several jurisdictions at the same time, the cost of delay is many times higher.
 

Author: Irina Kuheika, Inna Semenova and Yahor Kulazhenka.