Collection > Mes cartes and Mes items now render one tile per catalogue identity. Quantities are summed across acquisition rows; raw and graded copies of the same card are counted together, while sealed identities remain separate. Multiple-copy counts sit at the bottom right opposite the collector number. On card and sealed detail artwork, a multiple-copy count replaces the possession tick; a single copy keeps its tick and an unowned product keeps its existing absent indicator.

This is a presentation change, not a ledger merge. Conditions, languages, grading, purchase prices and original ownership ids remain intact. Sorting precedes grouping; the first sorted holding supplies the tile's representative metadata and unit quote, not a fabricated average. Existing portfolio valuation continues to use ledger rows.

Selecting a grouped tile selects all its underlying ownership ids. The explicit removal confirmation states the sum of copies concerned; no removal is triggered by opening a tile. Sealed tiles now open item detail instead of opening a removal sheet for an arbitrary acquisition. The legacy acquisition-ledger screen retains its per-row editing behavior.

Regression coverage includes immutable grouping, raw/slab and sealed separation, rendering one tile for two additions totalling five copies, navigation, grouped selection/deselection and the five-copy removal confirmation. Sealed detail tests assert that multiple copies replace the tick; card detail and badge placement have source-contract coverage. The non-mutating Maestro flow requires an existing duplicate fixture and must not clear account or collection data.

No backend deployment, migration, account change or data deletion is required.