When looking at the concept of FAIR USE one of the questions we need to answer is how much of a copyrighted work can we use without violating that copyright.
Like everything the answer is never simple. Tom Jones, CG in his lecture “Honesty, Courtesy, and Confidentiality: Ethics for Family Historians.” (available on CD from JAMB Productions) suggests using the “Rule of Three.” If you use more that three words, put it in quotes. If you use more than three paragraphs you need permission. This works well for books and many scholarly articles.
What happens, however, if you are talking about a BLOG? You might have only three paragraphs, putting them in quotes and reusing them is not justified under the fair use concept.
Universities generally suggest a 10% rule. If you use more than 10% you should have permission. This means 10% of each of the parts of a whole, so using more than 10% of the whole, of a part, of a section, of a chapter, of an article, etc. would violate the concept.
This works well in many cases, but think about a “How To” genealogy book. You might have a chapter on vital records, one on courthouse research and another on archives. Each of those might have a page or two devoted to each state in the US, or perhaps each county in a state. What if you took all the information on a particular state and use it in another publication. You would have most likely used less than 10% of any particular chapter or section, in fact perhaps as little as 2%. You would have used very little of the whole, definitely under 10%. Yet I think you would have violated the spirit of Fair Use by using all of the information on an identifiable topic.
So, to keep things easy, I suggest you use a combination the rule of 3 and the 10% rule. If you use more than 3 words put it in quotes, if you use more than the lesser of 3 paragraphs or 10% seek permission.
There are other factors involved in deciding whether a use of copyrighted material is fair, this at least is measurable. Set a standard for yourself and stick with it.
Want to read more? Check the following Copyright Blogs