Evidence organization in a trademark infringement lawsuit unfolds around four groups: proving you have the right, proving they infringe, proving your losses or their profits, and proving you sued the right party. None can be missing, and the infringement and damages groups decide who wins and how much is awarded.
1. Rights Evidence
- Trademark registration certificate, plus transfer, change, and renewal certificates, ensuring a continuous chain of title in a consistent name;
- Where suing as a licensee, attach the trademark license contract; exclusive or sole licensees may sue independently, while ordinary licensees need the registrant's express authorization;
- Where asserting a well-known trademark, attach well-knownness recognition records, years of use, market share, advertising, and other fame evidence.
2. Infringement Evidence
- Notarized purchase: purchase the infringing goods under a notary's witness, seal the physical goods, and obtain the notarial certificate—the most powerful infringement evidence;
- Page fixation: notarize or timestamp the e-commerce links and promotional pages, fixing the use of the sign, prices, and sales volumes;
- Comparison materials: a comparison statement between the accused sign and the registered trademark, and an analysis of the identity or similarity of the goods;
- Administrative and criminal materials: market regulation enforcement records and criminal judgments can be used directly as evidence.
3. Damages Evidence
- Your losses: sales decline data, financial statements, and receipts for reasonable enforcement expenses (notarization, attorney, travel);
- Their profits: sales volumes and unit prices on infringement pages, data obtained from platforms, and their account books (you may apply for the court to order production or for evidence preservation);
- Bad-faith evidence: records of service of warning letters and of the other side's repeat infringement, paving the way for punitive damages.
4. Party Identity Evidence
The defendant's business registration information and the online store's real-name information (obtainable through platform disclosure or a court investigation order); where multiple entities manufacture and sell in concert, they may be listed as co-defendants.
It is advisable to complete the main fixation of evidence before filing suit, especially for perishable web pages and physical goods; where necessary, apply for pre-litigation evidence preservation to prevent the other side from deleting links or moving inventory.
5. Service Entry
If you are facing these issues, you may first run a trademark monitoring check on MyTMBee, confirm feasibility, and then decide whether to file—avoiding blind filings that waste official fees.