In a website with user generated content, I provide an author bio under every article on the site. The author bio will be the same under every article the same author wrote. For some authors, the author bio is no longer then a couple of sentences, but for some descriptive writers, it is a good 100 words. These 100 words get repeated in almost 15 pages, some of them without substantial original content (such as haikus). Will this lead to duplicate content issues?
Read the explanation of "duplicate content" and you will see that a portion of a page as you are asking about will not incur a penalty http://googlewebmastercentral.blogspot.com/2008/09/demystifying-duplicate-content-penalty.html
Author bio is not considered duplicate content. There are some prominent blog and sites like searchenginewatch.com, searchengineland.com and searchenginejournal.com where many authors share their post but their author bio is same.
If Bio will consider duplicate content then it will also detect header and footer links and content as duplicate. My answer some of dynamic includes not count as duplicate content like Header content, Footer content, Author Bio and Your contact information's(Phone numbers).
Nope it's is not consider as Duplicate content. But yes if you doing article posting and you are using same text again and again in resource box than it might be a duplicate content.
I echo all the comments, the author bio is not considered as a delicate content. This is because; if you are posting many articles but the author bio will be the same for a single author. It will not going to change.
Author bio will not be considered as duplicate content because it is acceptable that one author is writing various articles. It is perfectly fine to have the same author bio everywhere.
Of course it's NOT a duplicated content. Don't forget that all of us are doing it. Also, you don't cound this bio as a content, as you could use it in another websites too. It's fine to use the same wherever you would like!
author bio is not duplicate content, rather its helpful for your blog authority. You will find that google loves this because it helps you integrate google authorship.
hello kamaldeep singh , I hope you got your answer that author bio is not a duplicate content. All the best