Mechanical Royalty Leakage and the MLC Unmatched Pool

1. Defining Mechanical Royalties in the Streaming Era

In the music industry, mechanical royalties are generated when a musical composition is reproduced or distributed in a physical or digital format. In digital streaming (interactive streaming on Spotify, Apple Music, Tidal, etc.), a stream is legally classified as both a public performance and a digital phono-record delivery (DPD).

Therefore, every stream triggers two composition payouts:

• Performance Royalties: Collected by Performing Rights Organizations (PROs like ASCAP, BMI, SESAC) and distributed to writers and publishers.
• Mechanical Royalties: Collected by mechanical licensing administrators (primarily The MLC in the United States) and distributed to publishers and self-administered songwriters.

Unlike master recording royalties, which flow directly from DSPs to distributors, mechanical royalties are governed by compulsory statutory rates set by the Copyright Royalty Board (CRB).

2. The MLC and the Origin of the "Unmatched Pool"

Under the Music Modernization Act (MMA) of 2018, The Mechanical Licensing Collective (The MLC) was established as the sole organization authorized to administer the blanket compulsory license for digital audio mechanicals in the United States. DSPs pay their blanket mechanical fees to The MLC along with detailed stream logs (usage files) identifying every track played via its ISRC.

The MLC maintains a database of registered musical works (ISWCs). When a DSP reports streams for a specific ISRC, The MLC searches its database to find the corresponding ISWC and its associated splits. If no metadata link exists, or if the work splits are incomplete or disputed, the royalty is placed into the MLC Unmatched Pool(the mechanical "Black Box").

3. Auditing the MLC Unmatched Queue Programmatically

To identify mechanical royalty leakage, rights holders must perform a forensic comparison of distributor logs against MLC statement records.

3.1 The Mechanical Shortfall Formula

For any reporting period, the expected mechanical royalty (R_{mech-expected}) for a publisher's share (W_s) is calculated as:

• S: Stream count reported by the distributor recording logs.
• Rate_CRB: The CRB statutory mechanical rate per stream (derived from DSP revenue pools, service provider configs, and publisher fractions).
• W_s: The publisher's fractional share of the composition (0 < W_s ≤ 1.0).

3.2 Identifying Anomalies via SQL

The audit system runs a database join over Arrow structures to identify discrepancies:

SELECT 
    r.isrc,
    c.iswc,
    SUM(r.total_streams) AS total_plays,
    (SUM(r.total_streams) * 0.0015 * c.writer_shares_percentage / 100) AS expected_mechanical,
    SUM(c.allocated_amount) AS actual_mechanical,
    ((SUM(r.total_streams) * 0.0015 * c.writer_shares_percentage / 100) - SUM(c.allocated_amount)) AS leakage
FROM recording_logs r
JOIN composition_statements c ON r.isrc = c.isrc
WHERE c.society_source = 'The MLC'
GROUP BY r.isrc, c.iswc
HAVING leakage > 0.01;

4. Resolving Claims with Royot

The Royot Engine automates the MLC recovery process:

• Ingestion: Normalizes client distributor TSVs and MLC statements via Polars, resolving currency conversion rates temporal to the stream dates.
• Stateful LangGraph Loop: Bridges missing links, resolving misspelled work titles and duration discrepancies.
• Dispute Generation: Generates MLC-compliant claim files mapping the necessary metadata parameters (ISRC, ISWC, Songwriter splits, DSP, Territory, and period).
• Direct Submission: Submits the packages to disputes@themlc.comvia the portal's integrated email dispatcher.