Which of the following is considered non-essential material in a patent application?

The correct answer is the background information on existing inventions, which is classified as non-essential material in a patent application. While the background section can provide context and may help the reader understand the invention's significance or the problems it aims to solve, it does not contribute directly to the claims or to the enablement of the invention. This material can be useful in framing the invention but is not required for the patent to be valid.

Claims detailing the invention steps are vital because they define the legal scope of the patent protection being sought. Data necessary for enabling the invention is also crucial since it ensures that the invention can be replicated by someone skilled in the art, ultimately fulfilling the requirement of utility and operability. Essential statistics regarding utility are critical for establishing that the invention is useful, another core requirement in patent law. Hence, while the background information plays a supportive role in understanding the invention, it does not impact the fundamental requirements necessary for the patent application process.