Is it a copyright infringement if it happens to match an existing work?
Conclusion: No copyright infringement if accidentally matched with an existing work
In order for copyright infringement to be established, it is necessary to rely on (use) the copyrighted work of another person and reproduce it tangibly.
One Rainy Night in Tokyo Case
This case is the theme of the movie "Moulin Rouge" composed by American composer Harry Warren by Domei Suzuki's song "One Rainy Night in Tokyo", which was released in 1963. It was a dispute over whether or not it relied on the song "Boulevard of Broken Dreams".
Below, the sentence
The author has the exclusive right to copy the copyright, and if a third party copies the copyright without the permission of the copyright holder, he / she must be liable for copyright infringement as a counterfeiter. However, the term "reproduction of a work" as used herein should be understood as referring to an existing work and remanufacturing something sufficient to make the content and format aware of the existing work. Even if a work with the same identity is created, if it is not reproduced based on an existing work, it does not mean that it has been duplicated and there is no room for the problem of copyright infringement. A work that relies on an existing work, regardless of whether or not a person who does not have the opportunity to come into contact with the existing work and therefore does not know its existence or content has made a mistake in not knowing it. Even if you create a work that is identical to an existing work, you do not have to be liable for copyright infringement.
Copyright reproduction is defined as "relying on an existing work and recreating something sufficient to make the content and format aware of it."
To be a copyrighted reproduction, you must rely on someone else's work.
Even if a work β happens to resemble an existing work α, if the author of the work β does not know the work α, it cannot be said that it depends on the work α, and the work It is not a copyright reproduction and does not constitute a copyright infringement.
If you do not have the opportunity to come into contact with a work of identity and create the same work without knowing its existence or content, that person will not be liable for copyright infringement, whether intentionally or negligently.
The theory states that (1) access to existing copyrighted works and (2) similarity of copyrighted works should be used to judge reliance.