The US Copyright Office refused to grant copyright protection for a logo that includes reversed text, which this image depicts. See [1]. Section IIIB of the aforementioned report contains justification for copyright ineligibility of the logo. Such justification can be adapted to this image.

The depicted text is ineligible for copyright and therefore in the public domain because it is not a “literary work” or other protected type in sense of the local copyright law. Facts, data, and unoriginal information which is common property without sufficiently creative authorship in a general typeface or basic handwriting, and simple geometric shapes are not protected by copyright. This tag does not generally apply to all images of texts. Particular countries can have different legal definition of the “literary work” as the subject of copyright and different courts' interpretation practices. Some countries protect almost every written work, while other countries protect distinctively artistic or scientific texts and databases only. Extent of creativeness, function and length of the text can be relevant. The copyright protection can be limited to the literary form – the included information itself can be excluded from protection.