© vs ℗ vs ™ vs ®

Four small marks, one drawer in most people's heads, and two entirely separate bodies of law. Copyright and trademark protect different things for different reasons, and within each pair the two symbols are not synonyms either: in both cases one of them is a claim anybody may make, and the other is a statement of fact about a public register or a moment of authorship.

The copyright sign covers a creative work — the text, the photograph, the film, the song as written. The sound recording copyright covers something narrower that most people never notice is separate: the particular fixed performance, which is its own work with its own owner, usually the label or the producer rather than the songwriter. That is why album packaging so often carries two notice lines whose years disagree. The composition can be from 1968 and the recording a remaster from 2011, and each carries its own claim. The ℗ line entered international law through Article 11 of the Rome Convention in 1961, was repeated by the Geneva Phonograms Convention a decade later, and sits in US law today at 17 U.S.C. § 402, which spells out its three parts: the symbol, the year of first publication, and the owner's name.

Neither copyright mark is required any more, which is the part that surprises people who assume the symbol is doing the work. Under the 1909 US Copyright Act, publishing without the correct notice could forfeit your rights outright, so the circled C was a genuine safeguard rather than a formality. When the United States joined the Berne Convention, effective 1989, notice became optional: a work is protected from the moment it is fixed in tangible form. The marks survived because they are still useful — they name an owner, date the work, and make it awkward for anyone to later claim they infringed innocently — but nothing about them is load-bearing.

The trademark pair works as a ladder instead. The small TM is an informal claim: append it to a product name at will, without registering anything, to announce that you treat the name as yours. It carries no official status, which is the source of both its usefulness and its emptiness. The circled R is the certificate — an assertion that a national trademark office has actually registered the mark — and in the United States it may not be used otherwise. The service mark does the ™ job for services rather than goods, and is largely a US convention that most of the world manages without.

All four are single characters, and none of them should be assembled by hand. ™ is the one that gets built wrongly most often: it is a pre-made superscript pairing of T and M, drawn to ride high and small against the last letter of a name, and a capital T and M shrunk in point size will not match it at any size. The parenthesised forms — (c), (R), (P) — are autocorrect stand-ins rather than the characters themselves. On a Mac, Option-G, Option-R and Option-2 give ©, ® and ™ directly; on Windows they are Alt+0169, Alt+0174 and Alt+0153. In HTML they are ©, ® and ™. ℗ has neither a shortcut nor a named entity, so it is ℗ or a paste.

The rule that keeps you out of trouble is restraint. Do not decorate a client's brand with ® without confirming that the registration exists; ™ is the safe, non-committal choice, and no mark at all is safer still, since none of these is a precondition for protection. And when ™ shows up in ordinary prose attached to a phrase nobody has ever registered, read it as tone rather than notice — the mark has become shorthand for flagging something as somebody's over-branded invention, which is a joke about trademarks rather than a claim to one.