diff --git a/superset-frontend/src/explore/controlUtils/standardizedFormData.test.ts b/superset-frontend/src/explore/controlUtils/standardizedFormData.test.ts
index 9c2dc91d0b8d..93e91d125a86 100644
--- a/superset-frontend/src/explore/controlUtils/standardizedFormData.test.ts
+++ b/superset-frontend/src/explore/controlUtils/standardizedFormData.test.ts
@@ -276,6 +276,18 @@ describe('should collect control values and create SFD', () => {
         metrics: formData.standardizedFormData.controls.metrics,
       }),
     });
+    // a target viz whose "Time shift" control offers inherit/custom choices
+    getChartControlPanelRegistry().registerValue('target_viz_inherit', {
+      controlPanelSections: [
+        sections.timeComparisonControls({}),
+        {
+          label: 'transform controls',
+          controlSetRows: publicControlFields
+            .filter(c => c !== 'time_compare')
+            .map(control => [control]),
+        },
+      ],
+    });
   });
 
   test('should avoid to overlap', () => {
@@ -344,6 +356,52 @@ describe('should collect control values and create SFD', () => {
     ]);
   });
 
+  test('strips inherit/custom time shifts when target viz does not support them', () => {
+    // Table/Big Number period-over-period offer "inherit" and "custom" time
+    // shifts; the timeseries advanced-analytics target (target_viz) does not.
+    // Carrying them over leaves un-removable tags on the new chart (SC-99170).
+    const store = {
+      ...sourceMockStore,
+      form_data: {
+        ...sourceMockFormData,
+        time_compare: ['1 year ago', 'inherit', 'custom'],
+      },
+    };
+    const sfd = new StandardizedFormData(store.form_data);
+    const { formData } = sfd.transform('target_viz', store);
+    // the free-form delta survives, the special markers are dropped
+    expect(formData.time_compare).toEqual(['1 year ago']);
+  });
+
+  test('preserves inherit/custom time shifts when target viz supports them', () => {
+    const store = {
+      ...sourceMockStore,
+      form_data: {
+        ...sourceMockFormData,
+        time_compare: ['1 year ago', 'inherit'],
+      },
+    };
+    const sfd = new StandardizedFormData(store.form_data);
+    const { formData } = sfd.transform('target_viz_inherit', store);
+    expect(formData.time_compare).toEqual(['1 year ago', 'inherit']);
+  });
+
+  test('clears time_compare to null when every shift is unsupported', () => {
+    // When only special markers carry over and none survive, the control value
+    // must serialize to null (not an empty array) so the target chart shows an
+    // empty "Time shift" rather than a stray tag (SC-99170).
+    const store = {
+      ...sourceMockStore,
+      form_data: {
+        ...sourceMockFormData,
+        time_compare: ['inherit', 'custom'],
+      },
+    };
+    const sfd = new StandardizedFormData(store.form_data);
+    const { formData } = sfd.transform('target_viz', store);
+    expect(formData.time_compare).toBeNull();
+  });
+
   test('should inherit standardizedFormData and memorizedFormData is LIFO', () => {
     // from source_viz to target_viz
     const sfd = new StandardizedFormData(sourceMockFormData);
diff --git a/superset-frontend/src/explore/controlUtils/standardizedFormData.ts b/superset-frontend/src/explore/controlUtils/standardizedFormData.ts
index 0462b9e3a1c6..1adf00d1ee7a 100644
--- a/superset-frontend/src/explore/controlUtils/standardizedFormData.ts
+++ b/superset-frontend/src/explore/controlUtils/standardizedFormData.ts
@@ -156,6 +156,41 @@ export class StandardizedFormData {
     return controls;
   }
 
+  // Time shifts only meaningful for viz types whose "Time shift" control offers
+  // them (Big Number / Table period-over-period). Other viz types reuse the same
+  // `time_compare` key without these choices.
+  private static specialTimeShifts = ['inherit', 'custom'];
+
+  // Drop `time_compare` markers the target viz can't honor so they don't carry
+  // over as un-removable tags when switching chart types.
+  static dropUnsupportedTimeShifts(
+    controlsState: Record<string, unknown>,
+  ): void {
+    const control = controlsState?.time_compare as
+      | { value?: unknown; choices?: unknown }
+      | undefined;
+    if (!control || !Array.isArray(control.value)) {
+      return;
+    }
+    const supportedChoices = new Set(
+      ensureIsArray(control.choices)
+        .filter(
+          (choice): choice is [string, string] =>
+            Array.isArray(choice) && typeof choice[0] === 'string',
+        )
+        .map(choice => choice[0]),
+    );
+    const filtered = control.value.filter(
+      (shift: unknown) =>
+        typeof shift !== 'string' ||
+        !StandardizedFormData.specialTimeShifts.includes(shift) ||
+        supportedChoices.has(shift),
+    );
+    if (filtered.length !== control.value.length) {
+      control.value = filtered.length ? filtered : null;
+    }
+  }
+
   private getLatestFormData(vizType: string): QueryFormData {
     if (this.has(vizType)) {
       return this.get(vizType);
@@ -215,6 +250,7 @@ export class StandardizedFormData {
       ...publicFormData,
       viz_type: targetVizType,
     });
+    StandardizedFormData.dropUnsupportedTimeShifts(targetControlsState);
     const targetFormData = {
       // eslint-disable-next-line @typescript-eslint/no-explicit-any
       ...getFormDataFromControls(targetControlsState as any),