Royal Mail and Hermes have responded to claims that undelivered parcels are being sold on eBay.
Dozens of parcels are being auctioned off, containing everything from jewellery to electrical goods.
Adverts show parcels laid out on the floor, with dozens of bids being placed by eBay customers.
One was titled “10x lost returned mail (Royal Mail/Hermes)” and claimed the items were in the original packaging.
Royal Mail said each year 500,000 parcels are undeliverable because they are either incorrectly addressed or have no address or the intended recipient has moved.
A spokesman said around 15 per cent of undeliverable items were sold off.
A Royal Mail spokesperson told us: “These are not items that are in course of transmission by post and would not have reached eBay via Royal Mail.
“When Royal Mail attempts to deliver items to customers and the items are undeliverable, we return these items to the Delivery Office.
“In some cases, the receiving customers do not want to collect these items which can often be of low value.
“When items are undeliverable, our policy is to return such items to the sender or retailer.
“Certain retailers, sometimes based overseas, may not want to deal with the administrative burden of managing the returns and associated shipping costs.
“As a result certain overseas retailers sometimes arrange for third-party service providers based in the UK to manage their returns for them.
“These retailers will then mark these third-party firms as the return address on any packaging.
“Once the third-party firms receive the items, they sometimes elect to sell these items by auction on online marketplaces.
“Where we have been made aware of items being sold in this way, we ask these companies to remove any customer details on the sites as well as make no reference to Royal Mail in line with our terms and conditions.”
A Hermes spokesperson said: “Some overseas retailers have a representative (clearance house) in the UK and this [is] where Hermes collects and returns items too.
“Hermes has no role in deciding what then happens to these returned items – they belong to the retailer – and the retailer or their representative decides on the next course of action.
“Hermes is not involved and would not legally be able to open these parcels and remove any personal data.”
Ebay said: “These listings would be banned under our chance listings policy, which states that all sellers must identify the exact contents of the package in the description”.