This blog post proposes adding a third trait, Claim, that would live alongside Copy and Clone. The goal of this trait is to improve Rust’s existing split, where types are categorized as either Copy (for “plain old data”¹ that is safe to memcpy) and Clone (for types that require executing custom code or which have destructors). This split has served Rust fairly well but also has some shortcomings that we’ve seen over time, including maintenance hazards, performance footguns, and (at times quite significant) ergonomic pain and user confusion.