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Yes, duplicate content can harm your e-commerce sites. It can confuse search engines, making it hard for your site to rank well. Here are some simple ways to deal with it:

Use Canonical Tags: This tells search engines which version of a page is the main one.
Unique Product Descriptions: Try to write unique descriptions for each product, even if they are similar.
Noindex, Follow Tags: For pages that you don't want indexed, use these tags to prevent search engines from listing them.

For a full guide on handling duplicate content, check out this blog: https://www.resultfirst.com/blog/ecommerce-seo/how-to-handle-duplicate-content-on-your-ecommerce-site/

I hope it will be helpful for you.

@Dr-Pete Thanks, exactly what I was looking for. Really thank you very much

With the caveat that this is a 7-yo thread -- I'd say that it's generally more of a filter these days (vs. a Capital-P penalty). The OEM or large resellers are almost always going to win these battles, and you'll be at a disadvantage if you duplicate their product descriptions word-for-word.

Can you still rank? Sure, but you're going to have an easier time if you can add some original value. If you aren't allowed to modify the info, is there anything you can add to it -- custom reviews (not from users, but say an editorial-style review), for example? You don't have to do it for thousands of products. You could start with ten or 25 top sellers and see how things go.

1. What do you suggest as a solution if you are a reseller of a product and you are using the same description as measurements, characteristics etc? Especially if your wholeseller demands not to alternate the titles and the descriptions.

2. Then you are saying that all resellers selling, for example, an X model of sports shoes will get penalised because they are using the same description? Test: take a phrase or a paragraph from the most authoritative brand and paste to google. You will have results from other resellers. They don't actually look "penalized" if you see their PA score...

I'm going to generally agree with (and thumb up) Mark, but a couple of additional comments:

(1) It really varies wildly. You can, with enough duplication, make your pages look thin enough to get filtered out. I don't think there's a fixed word-count or percentage, because it depends on the nature of the duplicate content, the non-duplicate content, the structure/code of the page, etc. Generally speaking, I would not add a long chunk of "Why Buy With Us" text - not only is it going to increase duplicate-content risks, but most people won't read it. Consider something short and punchy - maybe even an image or link that goes to a site with a full description. That way, most people will get the short message and people who are worried can get more details on a stand-alone page. You could even A/B test it - I suspect the long-form content may not be as powerful as you think.

(2) While duplicate content is not "penalized" in the traditional sense, the impact of it can approach penalty-like levels since the Panda updates.

(3) Definitely agreed with Mark that you have to watch both internal and external duplication. If you're a product reseller, for example, and you have a duplicate block in your own site AND you duplicate the manufacturer's product description, then you're at even more risk.

James- Great question.....let me provide a little guidance.....we have a bunch of ecommerce sites we help manage for SEO.I am going to lump together several of googles "focus areas" into one. They are duplicate content, shallow content and copied duplicate content. Because with an ecommerce site, all 3 of these items can be the same or interchangeable thing.   Here are the major issues/things to focus on:Alot of ecommerce sites, in the past, have been able to generate substantial SEO value by listing products in variations of sizes and colors and with brief descriptions , and then create 1,000's of pages of what used to be considered unique content; (Shallow content). THOSE DAYS ARE GONE.  Assuming you still have the standard information copied and pasted on every page, that you mention above, ideally you want 250 unique words of description of a product.  Bare minimum you should have 100 words.....and in addition to the on-page content, you should make sure your meta descriptions are unique. Remember, Unique means relevant content that is different.  With duplicate content issues, google isn't penalizing you to hurt your ranking but they will only give you SEO value for the page they think is unique...for example if you have 40 pages of the same product but small variations in color or size or sku, and little to differentiate the pages, then they will count those 40 pages as 1 page....you lose the opportunity to build 39 pages of unique content value. The last thing to be careful of is if you have product that other companies have.....(you are a distributor or supplier or wholesaler and not the manufacturer). Then the manufacturer posts standard info and a bunch of people copy it and use it. YOU WILL BE PENALIZED BY GOOGLE FOR THIS BECAUSE IT IS COPIED DUPLICATE CONTENT. Most important point to remphasis----you know you are going to have some duplicate content on a website......you know that it it likely that if you are selling different variations of the same product, that you will have alot of the same stuff.....again, make sure you have unique and different content focused on your keywords. Target at least 50% different or unique content on each page as a MINIMUM.....Hope this helps.Mark