A Conflict With a Counterparty? Not a Word Without Your Lawyer

Your counterparty has stopped being politely responsive and started asking questions that look like preparation for a lawsuit. Or is calling to "sort things out between ourselves". At that moment every reply you give, every payment you make and even your silence can become evidence against you, well before the matter reaches a courtroom. Case law reveals four typical traps that entrepreneurs fall into before any claim is filed.

The key points in 30 seconds

• Paying an invoice or using the goods without a signed contract signifies acceptance of its terms just as a signature does.
• Whatever you admitted in one dispute with a counterparty will be held against you in another.
• A contract signed by an employee without a power of attorney becomes binding on the company if the company has confirmed it by its own conduct, whether by payment, acceptance of performance or use of the result.
• Silence counts as consent only where the law or the contract itself expressly says so.
• Do not hand unsigned drafts of documents to a counterparty "for information".
• During a conflict, clear every letter, call, message and payment with your lawyer before it goes out, not afterwards.

Does paying an invoice mean accepting a contract you never signed?

The supplier sent a draft contract. You did not sign it, but you paid the first invoice and accepted the goods. The supplier treats the contract as being in force. Very often the supplier turns out to be right.

Back in 2009 the Supreme Court of Ukraine held that proof that the parties are in fact performing a contract in itself rules out any finding that the contract was never concluded. Payment, acceptance of goods, references to the terms of the contract in correspondence, sending a claim under that contract and similar steps can all be treated as confirmation, even without a signature.

We recommend checking the terms of a draft contract before the first payment rather than after it. Do you intend to challenge the very existence of the contract? Then do not perform a single one of its clauses, not even in part.

Can you deny what you have already admitted in another dispute?

Your counterparty is suing you under a contract concluded with them. In that dispute you do not deny that the document exists, and argue only about the amount of the debt. A year later you want to challenge that same contract as never concluded, this time in a separate action. The court will not support you.

In January 2026 the Supreme Court blocked precisely such an attempt: a party that acknowledged the existence of a contract in one dispute cannot assert the opposite in another. The point is not the fact of signature, it is consistency of position. This principle is known as estoppel, and it differs from issue preclusion, which concerns facts established by an earlier judgment.

Does this mean you can never change your position in court? No. You may refine your arguments. What is problematic is denying facts you yourself have acknowledged.

Every written position taken in negotiations, in pre-action correspondence or in an earlier dispute with the same counterparty becomes an argument for the future. Agree the wording with your lawyer even in a "minor" letter or message. On transactions set aside as harmful to creditors, see Fraudulent transactions.

A deputy director signed a contract without a power of attorney. What now?

The chief accountant or the deputy director signed an agreement without having authority to do so. Formally, the agreement does not bind the company. But if the company accepted performance, paid part of the price or continues to use what the agreement produced, it has confirmed the agreement by its conduct.

Article 241(1) of the Civil Code of Ukraine provides that subsequent approval of a transaction by the person represented makes that transaction valid from the moment it was entered into. Approval need not be in writing. An action that demonstrates acceptance is enough. These are known as conclusive actions, that is, conduct implying consent.

Have you discovered an agreement signed without authority? Send the counterparty a written objection immediately and halt any performance, even partial. Using the result in silence costs more than it appears to.

Does silence count as consent? Only on one condition

The counterparty writes: "If you do not object within five days, we shall consider the terms agreed." You say nothing in reply. Does that amount to consent?

No, unless the law or the contract itself has attributed that meaning to silence in advance. Article 205 of the Civil Code expressly provides that silence counts as an expression of will only in the cases established by a contract or by law.

There is a trap of a different kind here. Even where silence formally does not count as consent, your subsequent conduct, a payment or acceptance of goods, will confirm the agreement through the first mechanism on this list. Silence on its own is safe. Silence combined with conduct is another matter.

The counterparty wants evidence before filing suit. What can you withhold?

Before filing a claim, a counterparty will often try to obtain from you whatever their case is missing. It may be an unsigned draft contract or something else. Sometimes it comes as psychological pressure and phone calls, and sometimes as a piece of cunning on their part. A friendly letter, for example, asking you simply to confirm receipt of goods, which later becomes evidence of performance of the very contract you are disputing.

An attorney''s information request stands apart. It is not merely a request, it carries a legal obligation behind it. Article 24 of the Law of Ukraine "On the Bar and Practice of Law" requires a reply within 5 working days of receiving the request. The limits of that obligation are narrower than they appear. A request cannot demand consultations or legal analysis, only existing information and copies of existing documents. Restricted information, trade secrets and the personal data of third parties need not be provided. A refusal should be set out in writing with reasons rather than simply ignored.

Do not answer any of these requests on your own, and do not hand over a single document without your lawyer.

From the moment a conflict starts turning into pre-trial procedures, or the matter is heading towards a claim being filed, every letter, message, call and payment feeds one of the four constructions above.

Five typical mistakes a business owner makes in a pre-trial conflict

Mistake No. 1. Paying "just in case". The company pays the invoice hoping to negotiate later, and then tries to prove that there was no contract. The payment has already proved otherwise.

Mistake No. 2. Personal, informal correspondence with the counterparty. The head of the company or a sole proprietor decides simply to explain the situation over a messaging app while the conflict is still live. The court will read that correspondence as an admission of facts.

Mistake No. 3. Silently enjoying the results of a contract signed by an unauthorized person. The company learns of an agreement signed without authority, yet keeps using it while working out what to do next. Time taken to think it over costs you a finding that the agreement is valid.

Mistake No. 4. Answering an attorney''s request on your own. You answer the request in more detail than the law requires. The surplus information becomes evidence that does not help you.

Mistake No. 5. Handing over drafts for information. The counterparty asks you to send an earlier version of the contract so as to compare the wording. An unsigned draft, a draft contract carrying edits and comments in track changes, or pre-contractual correspondence, is capable of confirming the content of the arrangement in court.

The four traps at a glance

Situation	What it means legally	What not to do	What to do
You paid or accepted goods without signing	The contract is deemed concluded through actual performance	Do not perform a single clause if you intend to challenge the contract	Check the terms before the first payment
You acknowledged a fact in another dispute with the same counterparty	The court will not allow you to deny it in a new dispute	Do not give contradictory explanations in different proceedings	Agree your position with your lawyer in every letter
A deputy signed an agreement without a power of attorney	The company''s subsequent conduct may approve the agreement (Article 241 of the Civil Code)	Do not use the result while you are checking the authority	Object in writing and halt performance immediately
The counterparty asks you to confirm a fact or a document	Silence in itself is not consent, but conduct here may become consent	Do not reply or hand over documents straight away	Send a considered reply after speaking to your lawyer

Conclusions

1. It is your conduct that carries legal weight, not your signature alone. A payment, silence following certain events, and even a friendly letter are capable of substituting for consent or of working against you.
2. The position you take in one dispute with a counterparty constrains you in the next dispute with the same party.
3. An attorney''s information request is an obligation within clearly defined statutory limits, not an occasion for sharing surplus information.

Documentary substantiation matters not only in a dispute with a counterparty but also during a tax audit: see Business purpose in transactions with non-residents and What the tax authority sees in 2026.