How to File an Unfair‑competition Complaint in the Czech Republic

Knowing how to file an unfair competition complaint in the Czech Republic is the critical first step for any business, competitor, or consumer harmed by misleading advertising, imitation products, predatory pricing, or other anti‑competitive conduct. Czech law provides three distinct enforcement routes, an administrative complaint to the Office for the Protection of Competition (ÚOHS), a consumer complaint to the Czech Trade Inspection Authority (ČOI), or a civil court action for injunctive relief and damages, each with its own procedural requirements, timelines, and available remedies. The 2026 reform of Act No. 143/2001 Coll.

(the Competition Act) is expanding the ÚOHS enforcement toolkit with a new market‑intervention instrument and broader provisional powers, making the choice of forum and the framing of a complaint more strategically consequential than ever. This guide sets out every stage of the unfair competition complaint process in the Czech Republic, from eligibility and document preparation through filing, costs, deadlines, and the practical implications of the 2026 changes.

Overview of the Unfair‑Competition Complaint Process and Who It Applies To

Czech unfair‑competition law is anchored in Act No. 143/2001 Coll. (the Competition Act), which prohibits agreements restricting competition, abuse of dominance, and other anti‑competitive practices. The general unfair‑competition clause in the Czech Civil Code (Act No. 89/2012 Coll.) supplements public enforcement with private‑law remedies. Conduct caught by these rules ranges from misleading comparative advertising and trade‑secret misappropriation to secret rebate schemes and predatory pricing.

Three forums handle complaints, and the right choice depends on the nature of the harm and the remedy sought.

Quick Forum Comparison

• ÚOHS (Office for the Protection of Competition). Investigates anti‑competitive agreements, abuse of dominance, and market‑structure distortions. Can impose fines, cease‑and‑desist orders, behavioural and, under the 2026 reform, structural remedies. Best suited where the conduct has market‑wide impact or involves undertakings with significant market power.
• ČOI (Czech Trade Inspection Authority). Handles consumer‑facing unfair commercial practices, misleading advertising, deceptive labelling, warranty violations, and aggressive selling. Can order corrective measures and impose administrative fines. File here when the primary victim is the consumer rather than a competitor.
• Civil court. Awards injunctions, removal orders, corrective publications, and compensatory damages in private proceedings. Essential where the complainant seeks monetary compensation or a court‑ordered prohibition, and available in parallel with administrative routes.

The decision rule is straightforward: market‑level or structural distortions go to ÚOHS; consumer‑facing deception goes to ČOI; private damages and injunctive relief go to the courts. Parallel filings across forums are permissible and, in complex cases, advisable.

Eligibility and Prerequisites for Filing an Unfair‑Competition Complaint

Any natural or legal person may file an unfair competition complaint in the Czech Republic, provided they can identify facts suggesting anti‑competitive or unfair conduct. Standing is broad: competitors, suppliers, consumers, trade associations, and public bodies may all initiate proceedings. The Constitutional Court confirmed in its decision IV. ÚS 386/24 (21 May 2025) that ÚOHS has an obligation to assess complaints submitted by competitors prior to conducting on‑site inspections, reinforcing the procedural rights of complainants.

Standing Checklist

• Identity. Full legal name, registration or identification number, and contact details of the complainant.
• Interest or harm. Description of how the complainant is affected, direct competitive harm, consumer detriment, or knowledge of facts indicating market distortion.
• Representation. If filing through counsel, a signed power of attorney (apostilled if issued abroad).
• Foreign complainants. A company or individual outside the Czech Republic may file, provided the allegedly unfair conduct affects the Czech market. Practical requirements include certified Czech translations of key documents and, in most cases, appointment of a local representative or counsel.

Before filing, confirm whether the issue is properly characterised as a competition matter (ÚOHS), a consumer‑protection matter (ČOI), or a private‑law dispute (court). Gathering prima facie evidence, contracts, invoices, screenshots, pricing data, at this stage strengthens the complaint and accelerates the authority’s preliminary assessment.

Step‑by‑Step Procedure for Filing an Unfair‑Competition Complaint

The unfair competition complaint process in the Czech Republic follows four main stages, regardless of the forum. The specific filing channels, formats, and escalation paths differ between ÚOHS, ČOI, and the civil courts as set out below.

Step 1, Decide the Forum and Prepare the Complaint

Apply the decision tree outlined above: if the conduct distorts market competition or involves undertakings with significant market power, file with ÚOHS. If it involves consumer‑facing deception (misleading advertising, false labelling, warranty breaches), file with ČOI. If you need monetary damages or a court injunction, commence civil proceedings at the competent district court. In cases of systemic harm, consider filing with ÚOHS and simultaneously seeking an interim court injunction.

Where to file, exact channels:

• ÚOHS: Written complaint by post to the ÚOHS headquarters in Brno, by fax, or by email to posta@uohs.gov.cz.
• ČOI: Online via the ČOI complaint portal, by email to podatelna@coi.gov.cz, by post, or in person at any regional inspectorate.
• Civil court: File a statement of claim at the district court having jurisdiction over the respondent’s registered seat or the place where the harm occurred.

Step 2, Draft the Complaint

A well‑structured complaint significantly increases the likelihood of the authority opening a formal investigation. Include the following elements:

1. Identity of the complainant, full name, address, registration number, contact details.
2. Identity of the respondent(s), name, registered seat, identification number (if known).
3. Statement of facts, clear, chronological description of the allegedly unfair conduct, with dates, locations, and market context.
4. Legal basis, cite the relevant provision of Act No. 143/2001 Coll. or, for consumer matters, Act No. 634/1992 Coll. (Consumer Protection Act).
5. Evidence list, numbered index of attached documents (contracts, invoices, screenshots, witness statements, market data).
6. Requested remedy, specify whether you seek an investigation, cease‑and‑desist order, fine, market investigation (under the 2026 reform), interim measures, removal of the harmful state, corrective publication, or damages.
7. Signature, signed by the complainant or authorised counsel.

A sample opening line might read: “The complainant hereby submits this complaint pursuant to Act No. 143/2001 Coll. requesting that ÚOHS investigate the respondent’s conduct described below and impose appropriate remedial measures.”

Step 3, Submit and Secure Acknowledgement

For ÚOHS submissions, email the signed complaint as a PDF to posta@uohs.gov.cz or send it by registered post. Request a read receipt for email submissions and retain the certified delivery slip for postal filings. For ČOI, use the online complaint portal for the fastest confirmation. Mark any commercially sensitive attachments as “Confidential, business secret” and include a non‑confidential summary for the public file. The authority will typically acknowledge receipt within days, although formal confirmation of next steps may take longer.

Step 4, Respond to Information Requests and Escalate Where Necessary

After filing, ÚOHS conducts a preliminary assessment to determine whether to open a formal investigation. The Constitutional Court’s decision in IV. ÚS 386/24 requires ÚOHS to document its assessment of competitor complaints before conducting any on‑site inspection, which reinforces the complainant’s right to a reasoned response. During this phase the authority may request additional information or evidence, respond within the stated deadline (commonly 14–30 days) and seek an extension promptly if needed.

If the case warrants urgent action, request provisional measures from ÚOHS or file a parallel application for an interim court injunction. Where evidence is at risk of destruction, flag this explicitly in the complaint and ask for expedited handling. Balance the need to provide comprehensive evidence against the risk of disclosing commercially sensitive material: use the confidential‑annex procedure and strategic redaction to protect business secrets while enabling the authority’s assessment.

Consolidated Timeline and Step Table

Required Documents and Information for an Unfair‑Competition Complaint

The documents needed for a complaint vary by forum, but the core evidence package is consistent. Assemble the following before filing and maintain originals in a secure chain‑of‑custody log.

For complex market cases, consider supplementing the core package with an economic expert report analysing market shares, pricing trends, or barriers to entry. While not mandatory, such reports accelerate the authority’s assessment and demonstrate the seriousness of the complaint. Preserve all originals and keep certified copies; evidence that cannot be authenticated may be disregarded during the investigation.

Timeline and Key Deadlines for Filing an Unfair‑Competition Complaint

Czech competition authorities do not operate under a single statutory maximum for completing investigations. Timelines are case‑specific, driven by the complexity of the market, the volume of evidence, and whether on‑site inspections or cross‑border coordination are required. The Constitutional Court’s ruling in IV. ÚS 386/24 imposes a procedural discipline on ÚOHS, it must document its assessment of a complaint before escalating to inspection, but does not set a fixed calendar deadline for doing so.

The practical lesson is to act quickly. Evidence deteriorates, witnesses become unavailable, and market conditions shift. File the complaint as soon as a reasonable evidence package is assembled, and continue to supplement the file as additional material emerges. Where the respondent’s conduct is causing ongoing harm, pursue interim relief (from ÚOHS or a court) without waiting for the full investigation to conclude.

Costs, Fees, and Practical Financial Considerations

Filing an unfair competition complaint with a Czech regulator is generally free, making administrative enforcement the most cost‑effective first step. Civil court proceedings carry statutory filing fees, and all routes involve indirect costs for evidence preparation, legal counsel, and expert analysis.

The fee amounts above are indicative ranges. Court filing fees are governed by Act No. 549/1991 Sb. and depend on the monetary value of the claim; always confirm the current fee schedule with the filing court. Lawyer and expert fees are market‑driven and should be agreed in writing before engagement.

What Changes in 2026, Reform Implications for Complainants

The 2026 amendment to Act No. 143/2001 Coll. represents the most significant overhaul of Czech competition enforcement in over a decade. ÚOHS has described the reform as introducing “new competition tools” designed to deliver “more efficient competition law enforcement.” Three changes have direct, practical implications for anyone considering how to file an unfair competition complaint in the Czech Republic.

• New market‑intervention instrument. ÚOHS gains the power to conduct market investigations and impose structural or behavioural remedies, including divestitures and conduct obligations, even without a prior finding that a specific undertaking has infringed the Competition Act. Industry observers expect this tool to be deployed where systemic market features (high concentration, barriers to entry, parallel pricing) produce consumer harm. Complainants should frame their submissions to highlight market‑structure data and propose specific remedial outcomes.
• Expanded enforcement against natural persons. The reform broadens investigatory and sanctioning powers to reach the conduct of individual managers. The likely practical effect will be to increase personal accountability, making it important for complainants to document managerial involvement carefully and to liaise with counsel before disclosing personal communications or internal correspondence.
• Stronger provisional measures. Early indications suggest that ÚOHS will gain enhanced interim‑measure powers, enabling faster intervention where ongoing conduct threatens irreversible competitive harm. Complainants should request provisional measures at the point of filing where the evidence supports urgency, rather than waiting for the investigation to progress.

Important caveat: The 2026 reform was progressing through the legislative process as of August 2026. Specific provisions may be amended before final enactment. Complainants should verify the current status of the amendment on the ÚOHS website or through official legislative monitors before relying on the new powers in their filing strategy.

Adapting Your Complaint for the 2026 Regime

• Include market‑structure analysis (market shares, concentration data, entry barriers) to trigger the market‑investigation pathway.
• Specify the remedy you seek, a behavioural order, structural divestiture, or market recommendation, rather than leaving remedy selection entirely to the authority.
• Protect confidential evidence using the ÚOHS confidential‑annex procedure; the expanded powers increase the volume of information exchanged during investigations.
• Consider engaging an economic expert early to produce data that supports both a competition complaint and, if needed, a parallel civil damages claim.

Common Pitfalls and How to Avoid Them

• Insufficient factual specificity. Vague allegations without dates, names, or transactional detail will not pass preliminary assessment. Use the evidence checklist and attach indexed supporting documents.
• Filing in the wrong forum. Routing a consumer deception case to ÚOHS, or a market‑dominance complaint to ČOI, causes delay. Apply the forum decision tree before drafting.
• Missing or inadequate documentary evidence. A complaint without contracts, invoices, or screenshots is difficult for the authority to act on. Assemble the core document package before filing.
• Over‑redaction of evidence. Excessive redaction can prevent the authority from assessing the complaint properly. Use the confidential‑annex procedure instead of blanket redaction, it protects business secrets while keeping the evidence accessible to investigators.
• Failure to preserve evidence. Digital content, web pages, social‑media posts, pricing displays, can be removed without notice. Capture and archive evidence immediately using date‑stamped screenshots or web‑archive tools.
• Neglecting interim relief. Where the respondent’s conduct is causing ongoing harm, waiting for the full investigation to conclude can be costly. Request provisional measures from ÚOHS or file a parallel court application for an interim injunction.
• Ignoring the pre‑inspection assessment requirement. The Constitutional Court has ruled that ÚOHS must document its assessment of a complaint before conducting on‑site inspections. Complainants should ensure their filings contain sufficient factual detail to support this assessment and should follow up if no response is received within a reasonable period.

Sources

1. Office for the Protection of Competition (ÚOHS), Complaints
2. Office for the Protection of Competition, Legislation / Competition
3. ÚOHS, Press Release: New Competition Tools
4. Czech Trade Inspection Authority (ČOI), Complaints and Submission Guidance
5. Ministry of Industry and Trade (MPO), Where to Make a Complaint?
6. Constitutional Court, IV. ÚS 386/24 (Obligation to Assess Complaints Before Inspection)
7. OECD, Annual Report on Competition Policy Developments in the Czech Republic