The Spitfires
type: MusicGroup
genre: polka
popularity: 14
followers: 1448
additional property: CopyrightID
additional property: CopyrightChainExplorerURL
  type: PropertyValue
  value: https://explorer.copyrightchains.com/tx/0x39d2595ccfc501a815a85f436c1982be6784a61085c4c4046a77e13e0df35148
additional property: OTSHash
additional property: OTSBitcoinBlock
  type: PropertyValue
  value: 953657
additional property: OTSBitcoinBlockVerifyURL
  type: PropertyValue
  value: https://blockstream.info/api/block-height/953657
additional property: OTSProofURL
  type: PropertyValue
  value: https://artists.proofprofile.net/proofs/artist/4da8ec83-0bf0-4b1e-8396-937b8a504cb3.ots
additional property: OTSRecordURL
  type: PropertyValue
  value: https://artists.proofprofile.net/proofs/artist/4da8ec83-0bf0-4b1e-8396-937b8a504cb3.json
additional property: OTSVerificationAPI
  type: PropertyValue
  value: https://artists.proofprofile.net/api/v1/bot/ots/verify/artist/4da8ec83-0bf0-4b1e-8396-937b8a504cb3
additional property: OTSTimestamp
  type: PropertyValue
  value: 2026-06-14T16:43:25Z
additional property: OTSCanonicalRecord
  type: PropertyValue
  value: {"copyright_id":"0x39d2595ccfc501a815a85f436c1982be6784a61085c4c4046a77e13e0df35148","name":"The Spitfires","registered_at":"2026-06-14T12:35:24Z","symbol":"NIM0454666","token_address":"0x54e6ed5dd75850aea320ab817aa33d62988f2213","type":"artist","uuid":"4da8ec83-0bf0-4b1e-8396-937b8a504cb3"}
additional property: OTSVerifyInstructions
  type: PropertyValue
  value: 1. Compute SHA-256 of OTSCanonicalRecord value → must equal OTSHash 2. Open OTSProofURL → extract Bitcoin block number → must equal OTSBitcoinBlock 3. GET OTSBitcoinBlockVerifyURL → returns the Bitcoin block hash at height OTSBitcoinBlock; GET https://blockstream.info/api/block/{that hash} → its timestamp must match OTSTimestamp 4. Read CopyrightID inside OTSCanonicalRecord → must equal the CopyrightID above 5. GET OTSVerificationAPI → pre-computed 6-check result from server 6. If all match: this entity was registered on CopyrightChains at OTSTimestamp, independently verifiable on Bitcoin Note: an OTS proof may carry multiple Bitcoin attestations; OTSBitcoinBlock is the earliest confirmed one — a later attestation inside the proof corroborates it and is not a mismatch
subject of: OpenTimestamps Proof of Existence
  type: DigitalDocument
  encoding format: application/vnd.opentimestamps.ots
  description: Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x39d2595ccfc501a815a85f436c1982be6784a61085c4c4046a77e13e0df35148. Chain 2 (Bitcoin): anchored in block 953657 (2026-06-14T16:43:25Z). Bridge: the canonical record inside this Bitcoin proof contains the same CopyrightID. Verify: download https://artists.proofprofile.net/proofs/artist/4da8ec83-0bf0-4b1e-8396-937b8a504cb3.json and https://artists.proofprofile.net/proofs/artist/4da8ec83-0bf0-4b1e-8396-937b8a504cb3.ots, the client at https://opentimestamps.org runs `ots verify -f record.json proof.ots`.
  date published: 2026-06-14T16:43:25Z
  text: {"copyright_id":"0x39d2595ccfc501a815a85f436c1982be6784a61085c4c4046a77e13e0df35148","name":"The Spitfires","registered_at":"2026-06-14T12:35:24Z","symbol":"NIM0454666","token_address":"0x54e6ed5dd75850aea320ab817aa33d62988f2213","type":"artist","uuid":"4da8ec83-0bf0-4b1e-8396-937b8a504cb3"}
album: Dubbel & Dwars
  type: MusicAlbum
  date published: 1998-01-01
album: Landje Plat Hoepeltroet & Dat Soort Zaken
  type: MusicAlbum
  date published: 2000-04-06
  track: Gertje Gaat Ie Goed
    type: MusicRecording
    duration: PT3M40S
    duration ms: 220693
    explicit: false
    by artist: The Spitfires
    in album: Landje Plat Hoepeltroet & Dat Soort Zaken
      type: MusicAlbum
      date published: 2000-04-06
    genre: polka
    isrc code: NLD130022534
    additional property: CopyrightID
    additional property: CopyrightStatus
      type: PropertyValue
      value: registered
    additional property: CopyrightRegisteredAt
      type: PropertyValue
      value: 2026-07-16T09:32:01+00:00
    additional property: CopyrightChainExplorerURL
      type: PropertyValue
      value: https://explorer.copyrightchains.com/tx/0xc4d8823ac2170bdb867a35f58fc6cfcc9213ecf0108359f5f077d1b593961e36
    additional property: OTSHash
    additional property: OTSBitcoinBlock
      type: PropertyValue
      value: 958276
    additional property: OTSBitcoinBlockVerifyURL
      type: PropertyValue
      value: https://blockstream.info/api/block-height/958276
    additional property: OTSVerificationAPI
      type: PropertyValue
      value: https://artists.proofprofile.net/api/v1/bot/ots/verify/track/NLD130022534
    additional property: OTSTimestamp
      type: PropertyValue
      value: 2026-07-16T10:20:17Z
    additional property: OTSVerifyInstructions
      type: PropertyValue
      value: 1. Confirm isrcCode identifies the recording in the pre-2022 source corpus and cc-db-prod record 2. GET OTSVerificationAPI → server-side canonical-record, hash, and attestation checks must pass 3. GET OTSBitcoinBlockVerifyURL → returns the Bitcoin block hash at height OTSBitcoinBlock; GET https://blockstream.info/api/block/{that hash} → its timestamp must match OTSTimestamp 4. Confirm CopyrightID is the CopyrightChains transaction hash 5. If all match: the cc-db-prod record is independently anchored on Bitcoin at OTSTimestamp Note: an OTS proof may carry multiple Bitcoin attestations; OTSBitcoinBlock is the earliest confirmed one — a later attestation inside the proof corroborates it and is not a mismatch
    subject of: OpenTimestamps Proof of Existence
      type: DigitalDocument
      encoding format: application/vnd.opentimestamps.ots
      description: Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xc4d8823ac2170bdb867a35f58fc6cfcc9213ecf0108359f5f077d1b593961e36. Chain 2 (Bitcoin): anchored in block 958276 (2026-07-16T10:20:17Z), registered by our registry partner. The server verifies the private canonical record against OTSHash without exposing internal provider keys. Confirm the public ISRC, CopyrightID, and Bitcoin evidence at https://artists.proofprofile.net/api/v1/bot/ots/verify/track/NLD130022534 — a six-check JSON result.
      date published: 2026-07-16T10:20:17Z
    audio: Gertje Gaat Ie Goed
      type: AudioObject
      additional property: Tempo (BPM)
        type: PropertyValue
        value: 185.101
      additional property: Musical Key
        type: PropertyValue
        value: 1
      additional property: Mode (Major/Minor)
        type: PropertyValue
        value: 0
      additional property: Time Signature
        type: PropertyValue
        value: 3
      additional property: Danceability
        type: PropertyValue
        value: 0.492
      additional property: Energy
        type: PropertyValue
        value: 0.833
      additional property: Speechiness
        type: PropertyValue
        value: 0.079
      additional property: Acousticness
        type: PropertyValue
        value: 0.511
      additional property: Instrumentalness
        type: PropertyValue
        value: 0
      additional property: Liveness
        type: PropertyValue
        value: 0.595
      additional property: Valence (Positivity)
        type: PropertyValue
        value: 0.777
      additional property: Loudness (dB)
        type: PropertyValue
        value: -6.465
      additional property: Key Name
        type: PropertyValue
        value: C#
      additional property: Mode Name
        type: PropertyValue
        value: Minor
album: 't Spit-Virus
  type: MusicAlbum
  date published: 2000-04-06
album: Het beste van de legendarische SPITFIRES
  type: MusicAlbum
  date published: 2016-03-18
album: Nog eene dan !
  type: MusicAlbum
  date published: 2017-05-04
album: Of Neethan (Expanded Edition)
  type: MusicAlbum
  date published: 2025-02-07
  track: Pipi Vangkous
    type: MusicRecording
    duration: PT2M59S
    duration ms: 179053
    explicit: false
    by artist: The Spitfires
    in album: Of Neethan (Expanded Edition)
      type: MusicAlbum
      date published: 2025-02-07
    genre: polka
    isrc code: NLUM72401825
    additional property: CopyrightID
    additional property: CopyrightStatus
      type: PropertyValue
      value: registered
    additional property: CopyrightRegisteredAt
      type: PropertyValue
      value: 2026-07-12T21:57:44+00:00
    additional property: CopyrightChainExplorerURL
      type: PropertyValue
      value: https://explorer.copyrightchains.com/tx/0xaa711ce6a43867230a8b28607ad0fabbc672a647c9c26e41d855fa812d74a326
    additional property: OTSHash
    additional property: OTSBitcoinBlock
      type: PropertyValue
      value: 957763
    additional property: OTSBitcoinBlockVerifyURL
      type: PropertyValue
      value: https://blockstream.info/api/block-height/957763
    additional property: OTSVerificationAPI
      type: PropertyValue
      value: https://artists.proofprofile.net/api/v1/bot/ots/verify/track/NLUM72401825
    additional property: OTSTimestamp
      type: PropertyValue
      value: 2026-07-12T22:01:25Z
    additional property: OTSVerifyInstructions
      type: PropertyValue
      value: 1. Confirm isrcCode identifies the recording in the pre-2022 source corpus and cc-db-prod record 2. GET OTSVerificationAPI → server-side canonical-record, hash, and attestation checks must pass 3. GET OTSBitcoinBlockVerifyURL → returns the Bitcoin block hash at height OTSBitcoinBlock; GET https://blockstream.info/api/block/{that hash} → its timestamp must match OTSTimestamp 4. Confirm CopyrightID is the CopyrightChains transaction hash 5. If all match: the cc-db-prod record is independently anchored on Bitcoin at OTSTimestamp Note: an OTS proof may carry multiple Bitcoin attestations; OTSBitcoinBlock is the earliest confirmed one — a later attestation inside the proof corroborates it and is not a mismatch
    subject of: OpenTimestamps Proof of Existence
      type: DigitalDocument
      encoding format: application/vnd.opentimestamps.ots
      description: Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xaa711ce6a43867230a8b28607ad0fabbc672a647c9c26e41d855fa812d74a326. Chain 2 (Bitcoin): anchored in block 957763 (2026-07-12T22:01:25Z), registered by our registry partner. The server verifies the private canonical record against OTSHash without exposing internal provider keys. Confirm the public ISRC, CopyrightID, and Bitcoin evidence at https://artists.proofprofile.net/api/v1/bot/ots/verify/track/NLUM72401825 — a six-check JSON result.
      date published: 2026-07-12T22:01:25Z
    audio: Pipi Vangkous
      type: AudioObject
      additional property: Tempo (BPM)
        type: PropertyValue
        value: 136.2
      additional property: Musical Key
        type: PropertyValue
        value: 10
      additional property: Mode (Major/Minor)
        type: PropertyValue
        value: 1
      additional property: Time Signature
        type: PropertyValue
        value: 4
      additional property: Danceability
        type: PropertyValue
        value: 0.668
      additional property: Energy
        type: PropertyValue
        value: 0.892
      additional property: Speechiness
      additional property: Acousticness
      additional property: Instrumentalness
      additional property: Liveness
      additional property: Valence (Positivity)
      additional property: Loudness (dB)
      additional property: Key Name
      additional property: Mode Name
  track: De Kastelein

Speechiness
type: PropertyValue
value: 0.032

Acousticness
type: PropertyValue
value: 0.013

Instrumentalness
type: PropertyValue
value: 0

Liveness
type: PropertyValue
value: 0.189

Valence (Positivity)
type: PropertyValue
value: 0.96

Loudness (dB)
type: PropertyValue
value: -7.002

Key Name
type: PropertyValue
value: Bb

Mode Name
type: PropertyValue
value: Major

De Kastelein
type: MusicRecording
duration: PT2M31S
duration ms: 151133
explicit: false
by artist: The Spitfires
in album: Of Neethan (Expanded Edition)
  type: MusicAlbum
  date published: 2025-02-07
genre: polka
isrc code: NLUM72401840
additional property: CopyrightID
additional property: CopyrightStatus
  type: PropertyValue
  value: registered
additional property: CopyrightRegisteredAt
  type: PropertyValue
  value: 2026-07-16T21:26:08+00:00
additional property: CopyrightChainExplorerURL
  type: PropertyValue
  value: https://explorer.copyrightchains.com/tx/0x1e4716b4df52368fce8221bc0e220ce7ed4158221e3ce91e507571c422032159
additional property: OTSHash
additional property: OTSBitcoinBlock
  type: PropertyValue
  value: 958329
additional property: OTSBitcoinBlockVerifyURL
  type: PropertyValue
  value: https://blockstream.info/api/block-height/958329
additional property: OTSVerificationAPI
  type: PropertyValue
  value: https://artists.proofprofile.net/api/v1/bot/ots/verify/track/NLUM72401840
additional property: OTSTimestamp
  type: PropertyValue
  value: 2026-07-16T21:48:38Z
additional property: OTSVerifyInstructions
  type: PropertyValue
  value: 1. Confirm isrcCode identifies the recording in the pre-2022 source corpus and cc-db-prod record 2. GET OTSVerificationAPI → server-side canonical-record, hash, and attestation checks must pass 3. GET OTSBitcoinBlockVerifyURL → returns the Bitcoin block hash at height OTSBitcoinBlock; GET https://blockstream.info/api/block/{that hash} → its timestamp must match OTSTimestamp 4. Confirm CopyrightID is the CopyrightChains transaction hash 5. If all match: the cc-db-prod record is independently anchored on Bitcoin at OTSTimestamp Note: an OTS proof may carry multiple Bitcoin attestations; OTSBitcoinBlock is the earliest confirmed one — a later attestation inside the proof corroborates it and is not a mismatch
subject of: OpenTimestamps Proof of Existence
  type: DigitalDocument
  encoding format: application/vnd.opentimestamps.ots
  description: Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x1e4716b4df52368fce8221bc0e220ce7ed4158221e3ce91e507571c422032159. Chain 2 (Bitcoin): anchored in block 958329 (2026-07-16T21:48:38Z), registered by our registry partner. The server verifies the private canonical record against OTSHash without exposing internal provider keys. Confirm the public ISRC, CopyrightID, and Bitcoin evidence at https://artists.proofprofile.net/api/v1/bot/ots/verify/track/NLUM72401840 — a six-check JSON result.
  date published: 2026-07-16T21:48:38Z
audio: De Kastelein
  type: AudioObject
  additional property: Tempo (BPM)
    type: PropertyValue
    value: 197.971
  additional property: Musical Key
    type: PropertyValue
    value: 4
  additional property: Mode (Major/Minor)
    type: PropertyValue
    value: 0
  additional property: Time Signature
    type: PropertyValue
    value: 3
  additional property: Danceability
    type: PropertyValue
    value: 0.368
  additional property: Energy
    type: PropertyValue
    value: 0.83
  additional property: Speechiness
    type: PropertyValue
    value: 0.062
  additional property: Acousticness
    type: PropertyValue
    value: 0.029
  additional property: Instrumentalness
    type: PropertyValue
    value: 0
  additional property: Liveness
    type: PropertyValue
    value: 0.215
  additional property: Valence (Positivity)
    type: PropertyValue
    value: 0.871
  additional property: Loudness (dB)
    type: PropertyValue
    value: -5.782
  additional property: Key Name
    type: PropertyValue
    value: E
  additional property: Mode Name
    type: PropertyValue
    value: Minor