@@ -4,7 +4,9 @@
 
 The Studio dataset filter builder writes "Is empty" / "Is not empty" as the spec's `{ FIELD: { $empty: true } }` / `{ FIELD: { $empty: false } }` instead of `$exists` (objectui#10813).
 
-`dataset.filter` and `measure.filter` stored the pair as `{ FIELD: { $exists: false } }` / `{ FIELD: { $exists: true } }`. `$exists` is the spec's has-a-value test (`!= null`), so a text value of `''` or a multi-value `[]` was never "empty" there, while the same operator in the sharing-rule widget and in a saved view meant something else. `@objectstack/spec` 17.6.0 admits `$empty` (objectstack#20446), whose meaning is the column's DECLARED row of the spec's per-type table (ruling B on objectstack#20311): null or `''` on a text-like column, null or `[]` on a multi-value one, null alone on every other type. The analytics service answers it from the field's declared type and `multiple` on its SQL and ObjectQL strategies. The bridge keeps no copy of the table.
+`dataset.filter` and `measure.filter` stored the pair as `{ FIELD: { $exists: false } }` / `{ FIELD: { $exists: true } }`. `$exists` is the spec's has-a-value test (`!= null`), so a text value of `''` or a multi-value `[]` was never "empty" there, while the same operator in the sharing-rule widget and in a saved view meant something else. `@objectstack/spec` 17.6.0 admits `$empty` (objectstack#20446), whose meaning is the column's DECLARED row of the spec's per-type table (ruling B on objectstack#20311): null or `''` on a text-like column, null or `[]` on a multi-value one, null alone on every other type. The analytics service answers it from the field's declared type and `multiple` on its SQL and ObjectQL strategies. The spec's own face table declares one face that refuses it: the `driver-memory` analytics (cube) face, the lowest-priority fallback strategy (`MemoryAnalyticsService`), refuses a newly authored "Is empty" / "Is not empty" filter with `INVALID_FILTER` / 400, as it refuses `$null`, where it answered `$exists`. The bridge keeps no copy of the table.
+
+The `@objectstack/spec` dependency floor rises from `^17.5.0` to `^17.6.0`, because this package now writes `$empty`, which `@objectstack/spec` 17.5.0 declares staged and refuses.
 
 The read half reads `$empty` back as the pair, with a boolean flag only.
 
 
@@ -6,6 +6,8 @@
 
 The widget behind sharing-rule `criteria_json`, `relatedListFilter` and `summaryOperations.filter` used to write its own meaning of 「is empty」: `{ $or: [{ FIELD: { $in: [''] } }, { FIELD: { $null: true } }] }` and its complement `{ FIELD: { $nin: [''], $null: false } }`, i.e. "no value OR `''`" on every field type. The `''` member reached a number or date column as `IN ('')`, and a multi-value column (stored as JSON by the SQL driver) as an `$in` that driver refuses. `@objectstack/spec` 17.6.0 admits `$empty` to `FILTER_OPERATORS` (objectstack#20446), and its meaning is the field's DECLARED row of the spec's per-type table (ruling B on objectstack#20311): null or `''` on a text-like field, null or `[]` on a multi-value field, null alone on every other type. Every evaluator expands it itself (`expandEmptyOperator`), so the widget now writes the same token on every column type and keeps no copy of the table.
 
+The `@objectstack/spec` dependency floor rises from `^17.5.0` to `^17.6.0`, because this package now writes `$empty`, which `@objectstack/spec` 17.5.0 declares staged and refuses.
+
 `kvToCondition` reads `$empty` back as the pair, with a boolean flag only: any other flag stays the raw criteria it is, as every evaluator refuses it.
 
 **What moves for a stored rule.** Reading alone rewrites nothing: a criteria saved in either earlier shape (the objectui#10790 `$or` entry and `$nin` + `$null` pair, or the older `$in: [null, '']` / `$nin: [null, '']`) still opens as the same "Is empty" / "Is not empty" row, and an un-edited rule keeps its stored bytes and keeps matching as before. The next time the criteria is edited, those rows are written as `$empty`, which re-scopes the rule:
 
@@ -2,8 +2,8 @@
 '@object-ui/plugin-list': minor
 ---
 
-The list view's live query sends "Is empty" / "Is not empty" as the spec's `isempty` / `isnotempty`, which the spec lowers to `$empty`, instead of an equality to `null` (objectui#10813).
+The list view's live query sends "Is empty" / "Is not empty" as the spec's `isempty` / `isnotempty` instead of an equality to `null` (objectui#10813). `@objectstack/spec` 17.6.0 and later lower that pair to `$empty`; an earlier reader lowers it to `$null`, as it does the saved view's `is_empty`.
 
 `convertFilterGroupToAST` resolved the pair to `[FIELD, '=', null]` / `[FIELD, '!=', null]`, a null-only test, before `mapOperator` was consulted. The same rule saved into the view is persisted as `is_empty`, which `@objectstack/spec` 17.6.0 lowers to `$empty` (objectstack#20446): so one filter panel answered two record sets, depending on whether the view had been saved. The pair now takes the value-less path like `is_null`, and `mapOperator` gains `isempty` / `isnotempty` arms. The node is `[FIELD, 'isempty', null]`; the spec discards the third slot.
 
-**What moves.** Nothing is stored by this path. On a text-like column a row holding `''` is now "empty", and on a multi-value column a row holding `[]` is, matching the server's per-type answer for the saved view. On a `provider: 'value'` list a row with no key at all is now "empty" too: the equality to `null` did not select it there.
+**What moves.** Nothing is stored by this path. Against a 17.6.0 or later server, on a text-like column a row holding `''` is now "empty", and on a multi-value column a row holding `[]` is, matching the server's per-type answer for the saved view. On a `provider: 'value'` list a row with no key at all is now "empty" too: the equality to `null` did not select it there.