Hashtag searches for dupes of major brands - including Skims underwear and Deckers' (DECK.N) Ugg boots - have been viewed millions of times on TikTok.
Graphic shows pictures of four original products and their original prices under named brands compared with the prices of their 'dupe' counterparts.
Newer technologies like the Google Lens app allow people to take photos of items they like and find similar products for sale.
In other cases, dupe sellers opt to replicate the look of higher-priced originals with cheaper materials to maximize profit.
However, experts say dupe sellers have grown increasingly skilled at avoiding brand logos and other design features that could infringe existing patents or copyrights.
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