How will distributors and brokers know if they are given suspicious offers?
Wholesalers must be aware of the risk of receiving falsified or substandard medicinal products. Guidance from EU GDP Guidelines suggests conducting "due diligence" checks when contracting new suppliers, considering factors such as the supplier’s reputation, offers of medicinal products likely to be falsified, large or unusual offers, and abnormal pricing (see article 5.2 EU GDP Guidelines).
Suspicious offers may include:

• Products in high demand or supply shortages
• Communication through unconventional channels (e.g., WhatsApp)
• Urgency or unusually low prices
• Products with decommissioned identifiers or broken tamper-evident features
• Suppliers not listed in official databases (EudraGMDP for wholesalers, national repositories for brokers)
• Unverified availability or unexpected economic/geographical offers

Wholesalers must only obtain products from authorised entities, as specified in EU regulations. Products imported from third countries require a manufacturing/import authorisation.

What should wholesale distributors and brokers do if they learn of suspicious offers?
Wholesalers or brokers who encounter a suspicious offer must immediately contact the national competent authority and the marketing authorisation holder. This applies whether they are directly offered suspected falsified products or become aware of such offers to others, including when verifying unique identifiers for others.

Source:

EMA: Guidance on good manufacturing practice and good distribution practice: Questions and answers