What is the main distinction between a rejection and an objection in patent examination?

The main distinction between a rejection and an objection in patent examination hinges on the nature of the issues raised in relation to a patent application. A rejection is tied most directly to the determination that a claim is unpatentable, usually based on criteria set forth in patent laws, which include considerations of novelty, non-obviousness, and eligibility of subject matter.

When a claim is rejected, it indicates that the examiner has found that the claimed invention does not meet the necessary legal standards for patentability. This typically involves an evaluation of the claims against prior art or statutory requirements, giving rise to legal grounds that can lead to the refusal of a patent.

On the other hand, an objection addresses issues that may prevent the application from being processed without necessarily implying that the subject matter is unpatentable. An objection often pertains to form and can arise from concerns related to the clarity, definiteness, or overall compliance of the claims with the standards of patentability as set out in applicable rules and regulations but doesn't equate to a determination of patentability itself.

Therefore, the correct choice accurately reflects the core of what a rejection involves — a determination regarding the unpatentability of subject matter based on the examination process.