@@ -21,3 +21,10 @@ value OR the empty string, and its complement:
 Criteria saved in the old shape still open in the builder as the same row, and
 opening one rewrites nothing; the builder writes the new shape the next time any
 row of that criteria is edited.
+
+**Correction, 2026-10-03 (objectui#10813).** The two shapes above are not what this release
+writes. Later in the same release the pair moved to the spec's one 「is empty」 operator:
+"Is empty" stores `{ FIELD: { $empty: true } }` and "Is not empty" `{ FIELD: { $empty: false } }`,
+whose meaning is the field's declared row of the spec's per-type table rather than "no value OR
+the empty string" on every type. Criteria saved in either earlier shape still open as the same
+row and are written as `$empty` on their next edit (`.changeset/10813-filter-condition-empty-operator.md`).
@@ -0,0 +1,13 @@
+---
+'@object-ui/app-shell': minor
+---
+
+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 `$empty` (objectstack#20446), whose meaning is the column's DECLARED row of the spec's per-type table (ruling B on objectstack#20311): null or `''` on a text-like column, null or `[]` on a multi-value one, null alone on every other type. The analytics service answers it from the field's declared type and `multiple` on its SQL and ObjectQL strategies. The spec's own face table declares one face that refuses it: the `driver-memory` analytics (cube) face, the lowest-priority fallback strategy (`MemoryAnalyticsService`), refuses a newly authored "Is empty" / "Is not empty" filter with `INVALID_FILTER` / 400, where it answered `$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.
+
+**What moves for a stored filter.** A stored `$exists` no longer opens as "Is empty" / "Is not empty": it opens in the Source tab, with its bytes untouched, and keeps matching what it matched before. Opening it as the pair would let an edit to ANOTHER row rewrite it to `$empty` and move `''` / `[]` across the line, which the read-half invariant (objectui#10257) forbids, and this inspector offers no `exists` row. To move such a filter to the new meaning, remove the row and add "Is empty" again. Readable stores (this repository, objectstack, hotcrm and cloud) hold no `dataset.filter` with `$exists`.
@@ -0,0 +1,20 @@
+---
+'@object-ui/fields': minor
+---
+
+`FilterConditionField` writes "Is empty" / "Is not empty" as the spec's one 「is empty」 operator, `{ FIELD: { $empty: true } }` / `{ FIELD: { $empty: false } }` (objectui#10813).
+
+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 `$empty`, which re-scopes the rule:
+
+- text-like column: no change (both mean null or `''`);
+- every other single-valued column (number, boolean, date, datetime, time, select, a single lookup): a row holding `''` is no longer "empty" and becomes "not empty". Since objectstack#20308 the write door stores a cleared number, boolean, date, datetime or time as null, so on those types only a value written before it can hold `''`; a select or lookup can still hold one, and the spec's ruled table does not count it as empty;
+- multi-value column (multiselect, checkboxes, tags, or a `multiple: true` select, lookup or user): a row holding `[]` becomes "empty" and leaves "is not empty". On the SQL driver the earlier shape was refused outright, so a rule there starts running;
+- the `$in: [null, '']` shapes were refused by every objectstack filter face, so a rule still in them starts running.
+
+Measured on the installed 17.6.0 by-value readers (`@objectstack/formula`'s `matchesFilterCondition` and `ValueDataSource`) over null, an absent key, `''`, `[]` and set values: the `$or` entry and `$empty: true` disagree only on `[]`. Readable stores (this repository, objectstack, hotcrm and cloud) hold no criteria in either earlier shape.
@@ -0,0 +1,9 @@
+---
+'@object-ui/plugin-list': minor
+---
+
+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 `$empty` (objectstack#20446): so one filter panel answered two record sets, depending on whether the view had been saved. The pair now takes the value-less path like `is_null`, and `mapOperator` gains `isempty` / `isnotempty` arms. The node is `[FIELD, 'isempty', null]`; the spec discards the third slot.
+
+**What moves.** Nothing is stored by this path. Against a 17.6.0 or later server, on a text-like column a row holding `''` is now "empty", and on a multi-value column a row holding `[]` is, matching the server's per-type answer for the saved view. On a `provider: 'value'` list a row with no key at all is now "empty" too: the equality to `null` did not select it there.
@@ -75,3 +75,9 @@ objectui#9306's census), every pair emits the same node except
 folds onto `icontains` before a row leaves it. The vocabulary
 question this entry calls open is answered: the dropdown speaks the protocol's
 ids, and camelCase is the deprecated alias form.
+
+**Correction, 2026-10-03 (objectui#10813).** The two `isEmpty` / `isNotEmpty` arms that
+"resolve to a null comparison ahead of `mapOperator`" are gone in this release. The empty pair
+now takes the same value-less path as `is_null`, and `mapOperator` emits the spec's `isempty` /
+`isnotempty`, which the spec lowers to `$empty`; every spelling of the pair still emits one node
+(`.changeset/10813-list-view-empty-operator.md`).
@@ -85,7 +85,7 @@
     "@object-ui/types": "workspace:*",
     "@objectstack/formula": "^17.5.0",
     "@objectstack/lint": "^17.0.0",
-    "@objectstack/spec": "^17.5.0",
+    "@objectstack/spec": "^17.6.0",
     "@sentry/react": "^10.70.0",
     "jsonc-parser": "^3.3.1",
     "lucide-react": "^1.43.0",
 
@@ -44,7 +44,10 @@
  *
  * ⇒ reading only `$null` would have closed the composed route and left the
  * uncomposed one degrading exactly as before, for an author who picked "is not
- * empty" in the dataset filter inspector (which writes the `$exists` pair).
+ * empty" in the dataset filter inspector, which wrote the `$exists` pair until
+ * objectui#10813; a filter stored before then still carries it, and the row
+ * now writes `{ $empty: false }` instead, which this dialect carries on its
+ * `[empty]` arm (objectui#11547).
  *
  * ## What this card did NOT change
  *
 
@@ -120,8 +120,11 @@ export const RANGE_OP_PARAM: Record<string, string> = { $gte: 'gte', $lte: 'lte'
  *     that hands its own resolved filter straight to the escape hatch
  *     (`ObjectMetricWidget`, whose drawer renders `OpenInListButton`) passes
  *     through no canonicaliser at all, so `$exists` reaches this function
- *     verbatim — and the dataset filter inspector's "is not empty" row writes
- *     exactly that pair.
+ *     verbatim. The dataset filter inspector's "is not empty" row wrote
+ *     exactly that pair until objectui#10813, so a filter stored before then
+ *     still carries it; that row now writes `{ $empty: false }`, which is not
+ *     one of these two keys: it reaches this function verbatim too, and the
+ *     `[empty]` arm, {@link EMPTY_FILTER}, carries it (objectui#11547).
  *
  * ⚠️ A NON-boolean under either key says nothing about emptiness and writes
  * nothing, which is what it did before this pair existed.
 
@@ -102,9 +102,13 @@ describe('groupToCondition — the null predicates this inspector offers (object
     ).toEqual({ stage: { $null: true } });
   });
 
-  it('leaves the $exists pair exactly as it was', () => {
-    expect(groupToCondition(row('is_empty'))).toEqual({ closed_at: { $exists: false } });
-    expect(groupToCondition(row('is_not_empty'))).toEqual({ closed_at: { $exists: true } });
+  it('keeps the empty pair a predicate of its own — `$empty`, not `$null` (objectui#10813)', () => {
+    // This file's repair left the empty pair on `$exists`; objectui#10813 moved
+    // it to the spec's one 「is empty」 operator. Either way it is NOT the null
+    // pair: `$empty` also counts `''` on a text column and `[]` on a
+    // multi-value one, so folding the two would rewrite the author's choice.
+    expect(groupToCondition(row('is_empty'))).toEqual({ closed_at: { $empty: true } });
+    expect(groupToCondition(row('is_not_empty'))).toEqual({ closed_at: { $empty: false } });
   });
 
   it('still drops an operator it does not map, rather than emitting a wrong filter', () => {
 
@@ -208,7 +208,7 @@ describe('class 1 — an incomplete stored value is not opened as a row the next
   });
 
   it('CONTROL: the value-less tokens carry no value to be incomplete, and stay opened', () => {
-    for (const other of [{ name: { $exists: false } }, { name: { $null: true } }]) {
+    for (const other of [{ name: { $empty: true } }, { name: { $null: true } }]) {
       const { group, representable } = conditionToGroup(beside(other), FIELDS);
       expect(representable, JSON.stringify(other)).toBe(true);
       expect(editStage(group, 'lost')).toEqual({ $and: [{ stage: { $eq: 'lost' } }, other] });
@@ -224,7 +224,7 @@ describe('class 2 — a stored token is not opened as an operator the column\'s
     { stored: { amount: { $in: [1, 2] } }, type: 'number', readAs: 'in' },
     // "Every token" includes the value-less arms: the boolean bucket offers
     // only `equals` / `notEquals`.
-    { stored: { flag: { $exists: true } }, type: 'boolean', readAs: 'is_not_empty' },
+    { stored: { flag: { $empty: false } }, type: 'boolean', readAs: 'is_not_empty' },
     { stored: { flag: { $null: false } }, type: 'boolean', readAs: 'is_not_null' },
   ];
 
@@ -262,7 +262,7 @@ describe('class 2 — a stored token is not opened as an operator the column\'s
   });
 
   it('CONTROL: the value-less tokens on a column whose bucket offers them still open', () => {
-    for (const stored of [{ name: { $exists: true } }, { closed_at: { $null: false } }, { region: { $exists: false } }]) {
+    for (const stored of [{ name: { $empty: false } }, { closed_at: { $null: false } }, { region: { $empty: true } }]) {
       const { group, representable } = conditionToGroup(stored, FIELDS);
       expect(representable, JSON.stringify(stored)).toBe(true);
       expect(groupToCondition(group)).toEqual(stored);
@@ -315,7 +315,16 @@ describe('the invariant, swept: every row the read half opens, the panel draws a
       .flatMap((t) => SCALARS.map((v) => ({ stored: { [t]: v }, implicit: false }))),
     ...['$in', '$nin'].flatMap((t) => LISTS.map((v) => ({ stored: { [t]: v }, implicit: false }))),
     ...PAIRS.map((v) => ({ stored: { $between: v }, implicit: false })),
-    ...[true, false].flatMap((b) => [{ stored: { $exists: b }, implicit: false }, { stored: { $null: b }, implicit: false }]),
+    // `$empty` is what the empty pair writes since objectui#10813; `$exists`,
+    // what it wrote before, stays in the domain — it is now REFUSED (no
+    // operator this inspector offers reads it back), which the invariant
+    // accepts, and a read that still opened it would be named by the
+    // byte-identical check below.
+    ...[true, false].flatMap((b) => [
+      { stored: { $empty: b }, implicit: false },
+      { stored: { $exists: b }, implicit: false },
+      { stored: { $null: b }, implicit: false },
+    ]),
     ...[...SCALARS, ...LISTS].map((v) => ({ stored: v, implicit: true })),
   ];
Original file line number	Diff line number	Diff line change
`@@ -44,7 +44,10 @@`
`44`	`44`	`*`
`45`	`45`	* ⇒ reading only `$null` would have closed the composed route and left the
`46`	`46`	`* uncomposed one degrading exactly as before, for an author who picked "is not`
`47`		- * empty" in the dataset filter inspector (which writes the `$exists` pair).
	`47`	+ * empty" in the dataset filter inspector, which wrote the `$exists` pair until
	`48`	`+ * objectui#10813; a filter stored before then still carries it, and the row`
	`49`	+ * now writes `{ $empty: false }` instead, which this dialect carries on its
	`50`	+ * `[empty]` arm (objectui#11547).
`48`	`51`	`*`
`49`	`52`	`* ## What this card did NOT change`
`50`	`53`	`*`