Symbole copyright vs C encerclé

The copyright sign (©, U+00A9) is the internationally recognized legal symbol indicating copyright ownership, while the circled Latin capital C (Ⓒ, U+24B8) is an enclosed alphanumeric character from the Unicode Enclosed Alphanumerics block that merely looks similar. Only U+00A9 has legal significance; using U+24B8 in copyright notices could be considered legally invalid or at least ambiguous, depending on jurisdiction. The visual difference is subtle at small sizes but becomes apparent at larger sizes: U+00A9 typically has a thinner, smaller C inside a circle, while U+24B8 has a bolder C that fills more of the enclosing circle. In HTML, the copyright sign should be written as © or © — these named and numeric character references guarantee the correct character regardless of document encoding. A similar confusion arises with the sound recording copyright symbol ℗ (U+2117, SOUND RECORDING COPYRIGHT), which looks like a circled P and is distinct from both of the above.