There is no “30% Rule.”

I work with a lot of clients who are building their brands and their content, and one question I frequently get is “isn’t there a rule where you can copy something as long as you change 30% of it?”

This myth of the “30% rule” is pervasive and widely cited around the Internet, but it is simply false. There is no 30% rule, and any time you copy someone else’s writings, drawings, website, or other creative work, you run the risk of copyright infringement.

Many people think of copyright infringement as piracy or the creation of unauthorized reproductions of a copyrighted work, like a song, photograph, or writing. If you download a TV show, you are making an unauthorized copy of the TV show. However, the purpose of copyright law is to both reward ‘makers’ and incentivize others to create new artistic works, as opposed to merely taking the work done by others and claiming it as their own. Therefore, copyright protection extends beyond just ‘exact’ reproductions and into ‘substantially similar’ reproductions. But how far away does a work need to get before it is no longer confusingly similar?

The Myth of the 30% Rule and Things to Consider

According to internet lore, if you change 30% of a copyrighted work, it is no longer infringement and you can use it however you want. This, as a rule, is false. The truth of the matter is much more complicated.

While different courts have different legal tests, the key to determining whether something is substantially similar will depend on the similarities between the two works in context. This determination also changes depending on the medium.

If an infringer changes every tenth word in an 800-word article, for example, but keeps the perspective of the underlying work, the sentence structure, etc. in place, then it is likely to still be “substantially similar.”

It also depends on how much is copied: single words or short phrases are not subject to copyright protection, as copyright law is not meant to give a monopoly on those items. Also, there is a concept called “merger” wherein the idea and the expression of that idea are merged into one – essentially, if there is only one way to logically express an idea, then no one can claim exclusive ownership of that expression.

For example, the instructions in an instruction manual on how to operate a machine cannot be protected under copyright law – but the advertising and non-instructional materials can. A set of board game rules is not protectable under copyright law, but the ‘flavortext’ and narrative in the rulebook can.

Keep in mind there is a different analysis (called “fair use”) as to when you can use parts of someone else’s work for criticism, quoting, etc. This requires its own in-depth analysis but typically does not cover situations where a copier is attempting to pass off someone else’s work as their own.

Best Practices for Avoiding Copyright Infringement

When writing, read many different perspectives on issues and synthesize your own viewpoint and analysis. If you ultimately agree with an article that has been written, take the main idea and write your own article in your own words.


Don’t copy a blog post, change a few words, and pass it off as your own content. If you are quoting a blog post, quote thoughtfully and only take as much as needed to make your point. Otherwise, you could be exposing yourself to liability. Using an “article spinner” that changes some of the words of a work you don’t own can expose you to significant liability.

Be skeptical of who you hire for content. “I didn’t know what my contractor/employee was doing” is not a defense to copyright infringement. You may be held jointly and severally liable for the infringement, regardless if it was your contractor that was the actual infringer.

Don’t assume that content found on the internet can be freely copied without recourse. Businesses often spend hundreds of thousands of dollars on digital marketing and their advertising text is extremely valuable. Further, for SEO purposes, copies made and posted elsewhere detract from the uniqueness of the content and reduce its effectiveness in driving traffic to the creator’s website.

If you have questions about whether you can use someone else’s content in any way, contact an experienced intellectual property attorney to discuss – and they can help you to protect your own creative works from infringers as well!