Most of what artists worry about before delivery is not what stores check, and the most expensive metadata mistake in independent distribution does not produce a rejection at all. A rejection is cheap: the release bounces, you fix a field, you deliver again, nothing downstream has copied the error. The mistakes that pass validation cost money, because dozens of systems have ingested them by the time you notice. This article orders the failures by what they cost, not by how loudly they announce themselves.
The artist name is a key, not a label
The Music Biz Music Metadata Style Guide and Spotify say the same thing, mildly enough to hide what is at stake. Music Biz: "Artist name spelling should remain consistent for all content for an artist, where possible." Spotify: keep spelling and formatting consistent release to release, "including any punctuation, abbreviations, or acronyms."
That is not a style preference. To a store the primary artist string is not text to be displayed; it is the key that decides which existing identity a delivery belongs to. When a delivery arrives with a string that does not exactly match an existing identity, matching logic either attaches it to that artist or creates a new one — and anything reducing confidence (a spelling, a diacritic, a space, a script, a different byte sequence for the same visible glyph) pushes it toward a new one.
So one artist becomes two. The catalogue splits, so the streams split. The follower base does not migrate, so the second identity starts with no algorithmic history. Royalties still pay, against two accrual histories. Anything measured at catalogue level — editorial consideration, analytics, verification — is measured on half a career.
The failure modes are mundane: inconsistent diacritics — the Music Biz guide's own example is "Beyoncé vs. Beyoncè" — a trailing space, "DJ" versus "Dj", an ampersand in one release and "and" in the next, two Unicode representations of the same accented letter that are identical on screen.
What decides the cost is what happens next. Fixing a split page is not an edit but a merge request: your distributor asks each store to merge two identities, each store handles it separately with its own queue and evidence requirements, and some resolve it quickly while others never do. It is not a bug you fix. It is a claim you file, store by store.
The defence takes five minutes once. Write the canonical artist string down in a file and paste it into every delivery thereafter. Never retype it — retyping is where variants are born. In Arabic, Persian and Urdu script the same rule holds with a longer list of invisible ways to get it wrong, covered in Arabic, Persian and Urdu metadata that does not break.
The title field is display, not identity
The most common damaging entry in independent distribution is typing Artist A ft. Artist B into the title field while leaving the featured artist role empty.
People assume the store reads the title, sees "ft.", and works out the credit. It does not. The title field is a display string; it carries no identity. The featured artist gets no credit link, no appearance on their own page, no discovery path back to your record, nothing in their analytics — while the store may treat "ft. Artist B" as part of the song's name, producing the doubled display Song Name (feat. X) — Artist A, X that marks an amateur delivery on sight.
The stores publish this plainly. Spotify: "You shouldn't include any artists' names in your track or release titles," and in its provider documentation, "Spotify strongly recommends against including...references to 'Featured Artists' in track and product titles." Music Biz advises crediting featured artists "at the Artist role level and not add this data to the track or album release title."
The correct structure: the title field holds the song's name and nothing else, each act goes in its own role field, and the store generates every display string — including the "(feat. X)" you wanted — from the roles you filed.
Where a contract requires the billing in the title, both guides agree on form. Music Biz, on "feat." and "with": these "when included in the title are generally lowercase and in English." Apple: "Formatting of 'feat.' and 'with' must be lowercase, in English, not localized, and in parentheses or brackets." That "not localized" instruction is doing real work: "feat." is a machine-readable token, not a word.
The same rule governs remixers. Apple: "Remix tracks...must list the original artist as Primary with the remixer assigned the remixer role." Filing a remixer as primary artist is how remix catalogues pollute an artist's page. Roles are identity, titles are display, and putting identity in a display field destroys the identity and corrupts the display.
Version fields, and the term stores disagree about
The version field exists to distinguish two recordings that share a title. That is its entire job, and the test for whether to fill it in: if the original is the only version on the release, leave it empty. That is correct everywhere.
The vocabulary is stable: Radio Edit, Extended Mix, Live, Acoustic, Instrumental, Single Version, Alternate Take, Demo, Remastered, named remixes as Artist Name Remix. Music Biz directs you to parentheses first, brackets for any further detail: I Will Possess Your Heart (Originally Performed by Death Cab for Cutie) [Karaoke Instrumental Version].
"Radio Edit" is not a synonym for "the clean one." Music Biz reserves it for a version genuinely prepared for broadcast and directs you to "Edited Version" for a non-explicit edit. A Radio Edit is a length edit; an Edited Version is a content edit.
"Original Mix" is a genuine divergence between stores. Apple's guide disallows it: "The standard, original version of an album, track, or music video must not include any additional information in the title unless it is needed to identify the content," listing among disallowed terms "Exclusive, Limited Edition, Album Version, Original Mix, Tone, Alert Tone...Dolby Atmos, lossless, high-resolution audio." Spotify's publicly available metadata guidance publishes no rule naming "Original Mix"; its published position is the general one, that titles should not carry additional information. Meanwhile the label remains entrenched convention in electronic-music retail. So Apple names it disallowed, other services publish no rule either way, and treatment varies by store and by your distributor's pre-validation. Shipping an original plus remixes, expect at least one destination to strip or reject it.
And wherever a version field exists, use it rather than typing the version into the title: stores that build their own display strings will otherwise produce Song (Radio Edit) (Radio Edit).
The fields that exist, and what each one controls
A release is not one object but a hierarchy: a release (the product) contains recordings (the tracks), each embodying one or more works (the compositions). Each layer has its own identifier and its own money, and nearly every expensive mistake is a fact filed at the wrong layer. The transport itself is standardised: DDEX's Electronic Release Notification Message Suite (ERN).
| Field | Layer | What it actually controls |
|---|---|---|
| Primary artist | Recording | Which artist page it lands on; listener counts, followers, algorithmic history |
| Featured artist | Recording | Credit link to the featured act's page, without primary billing |
| Remixer | Recording | Remix credit without displacing the original artist |
| Composer, lyricist | Work | The path publishing and mechanical royalties are traced along |
| Version / subtitle | Recording | Distinguishes two recordings sharing a title |
| Explicit flag | Recording | A boolean, not a word in the title |
| Language of the work | Work | What is sung |
| Language of the title | Release / recording | How a store sorts, indexes and renders the title |
| P-line | Recording | Year and owner of the sound recording |
| C-line | Release | Year and owner of the artwork and packaging |
| Producer | Recording | A contributor credit — not a page, not a payment |
| Genre | Release | A routing signal, not a description of your taste |
| Release date | Release | When this product goes live |
| Original release date | Recording | When the recording was first published anywhere |
Four are confused routinely. P-line and C-line get copy-pasted into each other; the P-line year is the recording's first publication, not your upload date. Language of the work and language of the title legitimately differ: an instrumental with a Persian title has no lyric language, but it has a Persian title language. Original release date is not release date — filing a 2016 recording with a 2026 original release date tells every downstream system it is new. And the explicit flag is a boolean. Apple: "Explicit content must be flagged Explicit with a parental advisory tag. Terms like (Explicit)...must not be used for album...or track titles." Music Biz prohibits the reverse too — never write "Clean" or "Non-explicit" into a title.
On identifiers. An ISRC is twelve characters: two country, three registrant, two year-of-reference, five designation. Hyphens are a display convention, not part of the code, and there is no check digit in an ISRC. A UPC-A is twelve digits and an EAN-13 thirteen; prefixing a zero turns one into the other and the check digit does not change. The ISRC identifies the recording, so a re-release needs no new ISRC and the code stays with the recording when you change distributor — but a remix, edit, live version or instrumental is a materially different recording and requires its own.
A remaster is narrower than most people are told: the IFPI ISRC Handbook (§A.10.1) requires a new code only where the re-mastering "involve[s] the application of creative input to the recording itself," and explicitly excludes level change, invariant EQ or compression, de-noising, de-clicking, speed or pitch correction, sample-rate change and dithering. The practical rider is that a remaster sold as a separate track alongside the original is a separate product and needs its own code.
The rejection list, and how to pre-empt each item
The concrete reasons a delivery bounces, with the action that prevents each.
| Rejection reason | How to pre-empt it |
|---|---|
| Artist names inside title fields — "ft.", "feat.", "with", or a remixer's name typed into the title while the role sits empty | Title holds the song's name only; every act gets its own role field |
| Explicit or clean words in titles — "(Explicit)", "(Clean)", "(Non-explicit)" | Use the flag. Apple and Music Biz both prohibit the text form |
| Promotional or descriptive text — "Exclusive", "Limited Edition", "Album Version", "Original Mix", or format claims such as "Dolby Atmos" and "lossless" | Strip all of it; all are named in Apple's guide |
| Casing violations — all caps, all lowercase, random casing | Apply Music Biz title case, including its lowercase list: "a, an, and, as, but, for, from, nor, of, or, so, the, to, yet" plus prepositions of four letters or fewer. Exception only for a genuine, consistent artistic choice |
| Metadata that does not match the artwork | Compare title, artist and version on the cover against the fields, character by character |
| Wrong or missing language fields | Set both language of the work and language of the title, especially on non-Latin releases |
| Missing composer or lyricist | Fill both; some destinations reject outright. They take legal names, not stage names — rights societies match on the writer's registered name — every writer gets listed, and splits must total 100%, agreed in writing before release |
| Prohibited characters — emoji, decorative symbols, doubled spaces, stray invisible characters | Scan the strings rather than eyeballing them |
| Wrong identifiers — a reused ISRC on a materially different recording, or a UPC that fails its check digit | Verify the check digit; assign a new ISRC for any materially different recording |
| An artist name inconsistent with the existing catalogue | Paste the canonical string. This one often does not reject at all, which is why it is the most damaging item here |
Composer and lyricist deserve a note, because they are the entry whose worse outcome is passing. They never appear on the store front end, so a release with an empty composer field looks perfect and streams normally while its publishing royalties sit unmatched. Recording royalties fail loudly and publishing royalties fail silently: a broken artist page is visible within a day, an unmatched work can go unnoticed for years.
Notice what the list does and does not contain. Stores check the shape of your fields: what is in the title, whether the flag is set, whether identifiers are well-formed, whether required fields are filled. They do not check whether your artist name means what you meant, whether the featured artist you credited is the one you played with, or whether your splits match the agreement in the room. Validation catches format, not intent, and not consistency with your own past releases.
What to do before your next delivery
Run this in order before you submit:
- Paste the canonical artist string; do not type it.
- Confirm every title field holds only the song's name, every role has a field and every field has a role.
- Set both language fields.
- Check the P-line and the C-line separately.
- Set the original release date if this is not a first release.
- Verify the UPC check digit and confirm the ISRC belongs to this recording.
- Compare the artwork against the fields, character by character.
Mazufa hosts a free metadata checker at /metadata-checker. It runs entirely on your own device — nothing is uploaded — and flags several cases that are invisible on screen, including non-NFC strings, mixed digit sets and stray invisible characters.
Mazufa is free to release, takes 0% commission and no percentage of royalties received, and is invite-only with a human review of every complete application. Third-party costs outside our control — a payment provider's transfer fee, statutory withholding — are not a Mazufa deduction.
Every rejection is cheap. The errors that pass validation are the expensive ones.
Sources
- Music Business Association, Music Metadata Style Guide v2.1 — https://www.musicbiz.org/wp-content/uploads/2016/04/MusicMetadataStyleGuide_V2.1.pdf
- Apple Music Style Guide — https://help.apple.com/itc/musicstyleguide/en.lproj/static.html
- Spotify for Artists, Music metadata guidelines — https://support.spotify.com/us/artists/article/metadata-formatting-guidelines/
- Spotify Provider Support, Featured artist in a product or track title — https://providersupport.spotify.com/article/featured-artist-in-a-product-or-track-title
- IFPI, International Standard Recording Code (ISRC) Handbook (§A.10.1, re-mastering and creative input) — https://www.ifpi.org/wp-content/uploads/2021/02/ISRC_Handbook.pdf
- DDEX, Standards (including the Electronic Release Notification Message Suite, ERN) — https://ddex.net/standards/
On the limits of what is published. Every store rule stated here is quoted from that store's own public documentation. Three things artists are routinely told as fact are not published by any service and are not asserted here: the thresholds and evidence required for artist-page merges; the internal matching logic that decides whether a delivery joins an existing artist or creates a new one; and, beyond Apple's named prohibition, each store's treatment of "Original Mix".