You should be aware that certain creative works are not copyright protected.
Not all creative works are protected under federal copyright. The following categories are not protected:
intangible forms of work (for example, choreographed works that have not been documented or noted, spontaneous performances that have not been recorded or written)
titles, names, abbreviations, and slogans (note that names and slogans of companies may be trademarked)
recognizable symbols or designs, or variations on typographic ornamentation, typography, or colors component or content listings (ex: pure recipes or nutritional contents)
pure concepts (ex: you cannot copyright the concept of “spoon”)
techniques, methods, systems, or processes (for example, your company’s podcast production method cannot be copied).
concepts, principles, or discoveries (please keep in mind that although you may copyright the description, explanation, or illustration of such concepts, you cannot copyright the principles themselves since they are abstract notions)
the genetic code (note that if you create a gene, you can file for a patent)
unoriginal authorship or common property (ex: calendars, rulers, metric charts such as for height and weight)
Therefore, even if the work is a physical example of original writing, you cannot claim copyright in certain situations. For example, if you are employed to generate works for an employer, the employer, not you, owns the copyright.
