diff --git a/assertions.test.ts b/assertions.test.ts
new file mode 100644
index 00000000000..2ff81193779
--- /dev/null
+++ b/assertions.test.ts
@@ -0,0 +1,36 @@
+import assert from "node:assert/strict";
+import { assertValidFeatureReference } from "./assertions";
+
+describe("assertValidReference()", function () {
+  it("throws if target ID is a move", function () {
+    assert.throws(() => {
+      assertValidFeatureReference("a", "some-moving-feature", {
+        "some-moving-feature": { kind: "moved" },
+      });
+    });
+  });
+
+  it("throws if target ID is a split", function () {
+    assert.throws(() => {
+      assertValidFeatureReference("a", "some-split-feature", {
+        "some-split-feature": { kind: "split" },
+      });
+    });
+  });
+
+  it("throws if target ID is not defined", function () {
+    assert.throws(() => {
+      assertValidFeatureReference(
+        "a",
+        "this-is-a-completely-invalid-feature",
+        {},
+      );
+    });
+  });
+
+  it("does not throw if target ID is a feature", function () {
+    assert.doesNotThrow(() => {
+      assertValidFeatureReference("a", "dom", { dom: { kind: "feature" } });
+    });
+  });
+});
diff --git a/assertions.ts b/assertions.ts
new file mode 100644
index 00000000000..90d7a546f16
--- /dev/null
+++ b/assertions.ts
@@ -0,0 +1,29 @@
+import { isOrdinaryFeatureData } from "./type-guards";
+import { WebFeaturesData } from "./types.quicktype";
+
+/**
+ * Assert that a reference from one feature to another is an ordinary feature
+ * reference (i.e., it's defined and not some kind of redirect).
+ *
+ * @export
+ * @param {string} sourceId The feature that is referencing another feature
+ * @param {string} targetId The feature being referenced
+ * @param {WebFeaturesData["features"]} features Feature data
+ */
+export function assertValidFeatureReference(
+  sourceId: string,
+  targetId: string,
+  features: WebFeaturesData["features"],
+) {
+  const target: unknown = features[targetId];
+  if (target === undefined) {
+    throw new Error(`${sourceId} references a non-existent feature`);
+  }
+  if (!isOrdinaryFeatureData(target)) {
+    throw new Error(
+      `${sourceId} references a redirect "${targetId} instead of an ordinary feature ID`,
+    );
+  }
+}
+
+// TODO: assertValidSnapshotReference
diff --git a/features/conic-gradients.yml b/features/conic-gradients.yml
index 296df0f44ff..bbe65dfd98e 100644
--- a/features/conic-gradients.yml
+++ b/features/conic-gradients.yml
@@ -8,4 +8,5 @@ status:
 compat_features:
   - css.types.gradient.conic-gradient
   - css.types.gradient.conic-gradient.doubleposition
+  - css.types.gradient.conic-gradient.single_color_stop
   - css.types.gradient.repeating-conic-gradient
diff --git a/features/conic-gradients.yml.dist b/features/conic-gradients.yml.dist
index 9b55cfcd57f..ff1a7cb8638 100644
--- a/features/conic-gradients.yml.dist
+++ b/features/conic-gradients.yml.dist
@@ -41,3 +41,15 @@ compat_features:
   #   safari: "12.1"
   #   safari_ios: "12.2"
   - css.types.gradient.conic-gradient.doubleposition
+
+  # baseline: low
+  # baseline_low_date: 2025-04-04
+  # support:
+  #   chrome: "135"
+  #   chrome_android: "135"
+  #   edge: "135"
+  #   firefox: "136"
+  #   firefox_android: "136"
+  #   safari: "18.4"
+  #   safari_ios: "18.4"
+  - css.types.gradient.conic-gradient.single_color_stop
diff --git a/features/gradients.yml b/features/gradients.yml
index fe513c4390c..e95ec8fb792 100644
--- a/features/gradients.yml
+++ b/features/gradients.yml
@@ -16,18 +16,22 @@ compat_features:
   - css.types.gradient.linear-gradient.interpolation_hints
   - css.types.gradient.linear-gradient.premultiplied_gradients
   - css.types.gradient.linear-gradient.to
+  - css.types.gradient.linear-gradient.single_color_stop
   - css.types.gradient.linear-gradient.unitless_0_angle
   - css.types.gradient.repeating-linear-gradient
   - css.types.gradient.repeating-linear-gradient.doubleposition
   - css.types.gradient.repeating-linear-gradient.interpolation_hints
   - css.types.gradient.repeating-linear-gradient.to
+  - css.types.gradient.repeating-linear-gradient.single_color_stop
   - css.types.gradient.repeating-linear-gradient.unitless_0_angle
   - css.types.gradient.radial-gradient
   - css.types.gradient.radial-gradient.at
   - css.types.gradient.radial-gradient.doubleposition
   - css.types.gradient.radial-gradient.interpolation_hints
   - css.types.gradient.radial-gradient.premultiplied_gradients
+  - css.types.gradient.radial-gradient.single_color_stop
   - css.types.gradient.repeating-radial-gradient
   - css.types.gradient.repeating-radial-gradient.at
   - css.types.gradient.repeating-radial-gradient.doubleposition
   - css.types.gradient.repeating-radial-gradient.interpolation_hints
+  - css.types.gradient.repeating-radial-gradient.single_color_stop
diff --git a/features/gradients.yml.dist b/features/gradients.yml.dist
index f5ac728b631..625d60b9b77 100644
--- a/features/gradients.yml.dist
+++ b/features/gradients.yml.dist
@@ -145,3 +145,18 @@ compat_features:
   #   safari_ios: "15"
   - css.types.gradient.linear-gradient.premultiplied_gradients
   - css.types.gradient.radial-gradient.premultiplied_gradients
+
+  # baseline: low
+  # baseline_low_date: 2025-04-04
+  # support:
+  #   chrome: "135"
+  #   chrome_android: "135"
+  #   edge: "135"
+  #   firefox: "136"
+  #   firefox_android: "136"
+  #   safari: "18.4"
+  #   safari_ios: "18.4"
+  - css.types.gradient.linear-gradient.single_color_stop
+  - css.types.gradient.radial-gradient.single_color_stop
+  - css.types.gradient.repeating-linear-gradient.single_color_stop
+  - css.types.gradient.repeating-radial-gradient.single_color_stop
diff --git a/features/numeric-separators.yml b/features/numeric-separators.yml
new file mode 100644
index 00000000000..85500442056
--- /dev/null
+++ b/features/numeric-separators.yml
@@ -0,0 +1,6 @@
+name: Numeric separators
+description: To improve readability for numeric literals, underscores (`_`) can be used as separators. For example, `1_050.95` is equivalent to `1050.95`.
+spec: https://tc39.es/ecma262/multipage/ecmascript-language-lexical-grammar.html#prod-NumericLiteralSeparator
+group: javascript
+compat_features:
+  - javascript.grammar.numeric_separators
diff --git a/features/numeric-separators.yml.dist b/features/numeric-separators.yml.dist
new file mode 100644
index 00000000000..996e1916346
--- /dev/null
+++ b/features/numeric-separators.yml.dist
@@ -0,0 +1,17 @@
+# Generated from: numeric-separators.yml
+# Do not edit this file by hand. Edit the source file instead!
+
+status:
+  baseline: high
+  baseline_low_date: 2020-07-28
+  baseline_high_date: 2023-01-28
+  support:
+    chrome: "75"
+    chrome_android: "75"
+    edge: "79"
+    firefox: "70"
+    firefox_android: "79"
+    safari: "13"
+    safari_ios: "13"
+compat_features:
+  - javascript.grammar.numeric_separators
diff --git a/features/numeric-seperators.yml b/features/numeric-seperators.yml
index 85500442056..04c6806c7fd 100644
--- a/features/numeric-seperators.yml
+++ b/features/numeric-seperators.yml
@@ -1,6 +1,2 @@
-name: Numeric separators
-description: To improve readability for numeric literals, underscores (`_`) can be used as separators. For example, `1_050.95` is equivalent to `1050.95`.
-spec: https://tc39.es/ecma262/multipage/ecmascript-language-lexical-grammar.html#prod-NumericLiteralSeparator
-group: javascript
-compat_features:
-  - javascript.grammar.numeric_separators
+kind: moved
+redirect_target: numeric-separators
diff --git a/features/numeric-seperators.yml.dist b/features/numeric-seperators.yml.dist
index eaa3c384275..9bda2b05ad1 100644
--- a/features/numeric-seperators.yml.dist
+++ b/features/numeric-seperators.yml.dist
@@ -1,17 +1,6 @@
 # Generated from: numeric-seperators.yml
-# Do not edit this file by hand. Edit the source file instead!
+# This file intentionally left blank.
+# Do not edit this file.
+# The data for this feature has moved to numeric-separators.yml
 
-status:
-  baseline: high
-  baseline_low_date: 2020-07-28
-  baseline_high_date: 2023-01-28
-  support:
-    chrome: "75"
-    chrome_android: "75"
-    edge: "79"
-    firefox: "70"
-    firefox_android: "79"
-    safari: "13"
-    safari_ios: "13"
-compat_features:
-  - javascript.grammar.numeric_separators
+{}
diff --git a/features/single-color-gradients.yml b/features/single-color-gradients.yml
index b8e1a4789ba..5d1e93a8ee5 100644
--- a/features/single-color-gradients.yml
+++ b/features/single-color-gradients.yml
@@ -1,11 +1,4 @@
-name: Single color stop gradients
-description: A single color stop can be provided to the `linear-gradient()`, `radial-gradient()`, and `conic-gradient()` CSS functions, and their repeating counterparts, to create a solid color background.
-spec: https://drafts.csswg.org/css-images-4/#color-stop-syntax
-group: gradients
-compat_features:
-  - css.types.gradient.conic-gradient.single_color_stop
-  - css.types.gradient.linear-gradient.single_color_stop
-  - css.types.gradient.radial-gradient.single_color_stop
-  - css.types.gradient.repeating-conic-gradient.single_color_stop
-  - css.types.gradient.repeating-linear-gradient.single_color_stop
-  - css.types.gradient.repeating-radial-gradient.single_color_stop
+kind: split
+redirect_targets:
+  - gradients
+  - conic-gradients
diff --git a/features/single-color-gradients.yml.dist b/features/single-color-gradients.yml.dist
index 38d174ab005..e7dfa57a3c0 100644
--- a/features/single-color-gradients.yml.dist
+++ b/features/single-color-gradients.yml.dist
@@ -1,21 +1,8 @@
 # Generated from: single-color-gradients.yml
-# Do not edit this file by hand. Edit the source file instead!
+# This file intentionally left blank.
+# Do not edit this file.
+# The data for this feature has moved to:
+#   - gradients.yml
+#   - conic-gradients.yml
 
-status:
-  baseline: low
-  baseline_low_date: 2025-04-04
-  support:
-    chrome: "135"
-    chrome_android: "135"
-    edge: "135"
-    firefox: "136"
-    firefox_android: "136"
-    safari: "18.4"
-    safari_ios: "18.4"
-compat_features:
-  - css.types.gradient.conic-gradient.single_color_stop
-  - css.types.gradient.linear-gradient.single_color_stop
-  - css.types.gradient.radial-gradient.single_color_stop
-  - css.types.gradient.repeating-conic-gradient.single_color_stop
-  - css.types.gradient.repeating-linear-gradient.single_color_stop
-  - css.types.gradient.repeating-radial-gradient.single_color_stop
+{}
diff --git a/index.ts b/index.ts
index 3cefc981622..c7f7789bd5d 100644
--- a/index.ts
+++ b/index.ts
@@ -5,10 +5,12 @@ import { Temporal } from '@js-temporal/polyfill';
 import { fdir } from 'fdir';
 import YAML from 'yaml';
 import { convertMarkdown } from "./text";
-import { FeatureData, GroupData, SnapshotData, WebFeaturesData } from './types';
+import { GroupData, SnapshotData, WebFeaturesData } from './types';
 
 import { BASELINE_LOW_TO_HIGH_DURATION, coreBrowserSet, parseRangedDateString } from 'compute-baseline';
 import { Compat } from 'compute-baseline/browser-compat-data';
+import { assertValidFeatureReference } from './assertions';
+import { isMoved, isSplit } from './type-guards';
 
 // The longest name allowed, to allow for compact display.
 const nameMaxLength = 80;
@@ -120,7 +122,7 @@ function* identifiers(value) {
 // Map from BCD keys/paths to web-features identifiers.
 const bcdToFeatureId: Map<string, string> = new Map();
 
-const features: { [key: string]: FeatureData } = {};
+const features: WebFeaturesData["features"] = {};
 for (const [key, data] of yamlEntries('features')) {
     // Draft features reserve an identifier but aren't complete yet. Skip them.
     if (data[draft]) {
@@ -130,6 +132,11 @@ for (const [key, data] of yamlEntries('features')) {
         continue;
     }
 
+    // Attach `kind: feature` to ordinary features
+    if (!isMoved(data) && !isSplit(data)) {
+        data.kind = "feature";
+    }
+
     // Convert markdown to text+HTML.
     if (data.description) {
         const { text, html } = convertMarkdown(data.description);
@@ -185,12 +192,25 @@ for (const [key, data] of yamlEntries('features')) {
     features[key] = data;
 }
 
-// Assert that discouraged feature's alternatives are valid
 for (const [id, feature] of Object.entries(features)) {
-    for (const alternative of feature.discouraged?.alternatives ?? []) {
-        if (!(alternative in features)) {
-            throw new Error(`${id}'s alternative "${alternative}" is not a valid feature ID`);
-        }
+    const { kind } = feature;
+    switch (kind) {
+        case "feature":
+            for (const alternative of feature.discouraged?.alternatives ?? []) {
+                assertValidFeatureReference(id, alternative, features)
+            }
+            break;
+        case "moved":
+            assertValidFeatureReference(id, feature.redirect_target, features);
+            break;
+        case "split":
+            for (const target of feature.redirect_targets) {
+                assertValidFeatureReference(id, target, features);
+            }
+            break;
+        default:
+            kind satisfies never;
+            throw new Error(`Unhandled feature kind ${kind}}`);
     }
 }
 
diff --git a/package-lock.json b/package-lock.json
index 1098dab41cc..1c5013b1896 100644
--- a/package-lock.json
+++ b/package-lock.json
@@ -26,6 +26,7 @@
         "fast-json-stable-stringify": "^2.1.0",
         "fdir": "^6.5.0",
         "hast-util-to-string": "^3.0.1",
+        "mocha": "^11.7.2",
         "prettier": "^3.6.2",
         "quicktype": "^23.2.6",
         "rehype-parse": "^9.0.1",
@@ -6581,11 +6582,9 @@
       "devDependencies": {
         "@types/chai": "^5.2.2",
         "@types/chai-jest-snapshot": "^1.3.8",
-        "@types/mocha": "^10.0.10",
         "c8": "^10.1.3",
         "chai": "^6.0.1",
-        "chai-jest-snapshot": "^2.0.0",
-        "mocha": "^11.7.2"
+        "chai-jest-snapshot": "^2.0.0"
       },
       "peerDependencies": {
         "@mdn/browser-compat-data": "^7.0.0"
diff --git a/package.json b/package.json
index 260d6398c32..e56de968dc7 100644
--- a/package.json
+++ b/package.json
@@ -29,11 +29,12 @@
     "test:coverage": "npm run --workspaces test:coverage",
     "test:dist": "tsx scripts/dist.ts --check",
     "test:format": "prettier --check .",
+    "test:index": "mocha -r tsx './*.test.ts'",
     "test:lint": "npx eslint .",
     "test:schematypes": "tsx scripts/schema.ts",
     "test:specs": "tsx scripts/specs.ts",
     "test:types": "npm run --workspaces test:types && tsc",
-    "test": "npm run test:caniuse -- --quiet && npm run test:schematypes && npm run test:specs && npm run test:types && npm run test:format && npm run test:dist && npm run test --workspaces && npm run test:lint",
+    "test": "npm run test:caniuse -- --quiet && npm run test:schematypes && npm run test:specs && npm run test:types && npm run test:format && npm run test:index && npm run test:dist && npm test --workspaces && npm run test:lint",
     "update-drafts": "tsx scripts/update-drafts.ts",
     "remove-tagged-compat-features": "tsx scripts/remove-tagged-compat-features.ts && npm run format"
   },
@@ -53,6 +54,7 @@
     "fast-json-stable-stringify": "^2.1.0",
     "fdir": "^6.5.0",
     "hast-util-to-string": "^3.0.1",
+    "mocha": "^11.7.2",
     "prettier": "^3.6.2",
     "quicktype": "^23.2.6",
     "rehype-parse": "^9.0.1",
diff --git a/packages/compute-baseline/package.json b/packages/compute-baseline/package.json
index 8fcf340d2fb..fa1abe85965 100644
--- a/packages/compute-baseline/package.json
+++ b/packages/compute-baseline/package.json
@@ -28,11 +28,9 @@
   "devDependencies": {
     "@types/chai": "^5.2.2",
     "@types/chai-jest-snapshot": "^1.3.8",
-    "@types/mocha": "^10.0.10",
     "c8": "^10.1.3",
     "chai": "^6.0.1",
-    "chai-jest-snapshot": "^2.0.0",
-    "mocha": "^11.7.2"
+    "chai-jest-snapshot": "^2.0.0"
   },
   "peerDependencies": {
     "@mdn/browser-compat-data": "^7.0.0"
diff --git a/schemas/data.schema.json b/schemas/data.schema.json
index 1d4f5f899d1..7ee7b28da67 100644
--- a/schemas/data.schema.json
+++ b/schemas/data.schema.json
@@ -44,7 +44,18 @@
       "description": "Feature identifiers and data",
       "type": "object",
       "additionalProperties": {
-        "$ref": "#/definitions/FeatureData"
+        "oneOf": [
+          {
+            "$ref": "#/definitions/FeatureData"
+          },
+          {
+            "$ref": "#/definitions/FeatureMovedData"
+          },
+          {
+            "$ref": "#/definitions/FeatureSplitData"
+          }
+        ],
+        "$comment": "Use the `kind` property as a discriminator."
       }
     },
     "groups": {
@@ -102,6 +113,9 @@
       "description": "A feature data entry",
       "type": "object",
       "properties": {
+        "kind": {
+          "const": "feature"
+        },
         "name": {
           "description": "Short name",
           "type": "string"
@@ -143,7 +157,44 @@
           "$ref": "#/definitions/Discouraged"
         }
       },
-      "required": ["name", "description", "description_html", "spec", "status"],
+      "required": [
+        "kind",
+        "name",
+        "description",
+        "description_html",
+        "spec",
+        "status"
+      ],
+      "additionalProperties": false
+    },
+    "FeatureMovedData": {
+      "description": "A feature has permanently moved to exactly one other ID",
+      "type": "object",
+      "properties": {
+        "kind": {
+          "const": "moved"
+        },
+        "redirect_target": {
+          "description": "The new ID for this feature",
+          "type": "string"
+        }
+      },
+      "required": ["kind", "redirect_target"],
+      "additionalProperties": false
+    },
+    "FeatureSplitData": {
+      "description": "A feature has split into two or more other features",
+      "type": "object",
+      "properties": {
+        "kind": {
+          "const": "split"
+        },
+        "redirect_targets": {
+          "description": "The new IDs for this feature",
+          "$ref": "#/definitions/Strings"
+        }
+      },
+      "required": ["kind", "redirect_targets"],
       "additionalProperties": false
     },
     "GroupData": {
@@ -161,6 +212,37 @@
       "required": ["name"],
       "additionalProperties": false
     },
+    "Release": {
+      "description": "Browser release information",
+      "type": "object",
+      "properties": {
+        "version": {
+          "description": "The version string, as in \"10\" or \"17.1\"",
+          "type": "string"
+        },
+        "date": {
+          "description": " The release date, as in \"2023-12-11\"",
+          "type": "string"
+        }
+      },
+      "required": ["version", "date"],
+      "additionalProperties": false
+    },
+    "SnapshotData": {
+      "type": "object",
+      "properties": {
+        "name": {
+          "description": "Short name",
+          "type": "string"
+        },
+        "spec": {
+          "description": "Specification",
+          "type": "string"
+        }
+      },
+      "required": ["name", "spec"],
+      "additionalProperties": false
+    },
     "Status": {
       "type": "object",
       "properties": {
@@ -226,37 +308,6 @@
       "required": ["baseline", "support"],
       "additionalProperties": false
     },
-    "Release": {
-      "description": "Browser release information",
-      "type": "object",
-      "properties": {
-        "version": {
-          "description": "The version string, as in \"10\" or \"17.1\"",
-          "type": "string"
-        },
-        "date": {
-          "description": " The release date, as in \"2023-12-11\"",
-          "type": "string"
-        }
-      },
-      "required": ["version", "date"],
-      "additionalProperties": false
-    },
-    "SnapshotData": {
-      "type": "object",
-      "properties": {
-        "name": {
-          "description": "Short name",
-          "type": "string"
-        },
-        "spec": {
-          "description": "Specification",
-          "$ref": "#/definitions/URL"
-        }
-      },
-      "required": ["name", "spec"],
-      "additionalProperties": false
-    },
     "StringOrStrings": {
       "oneOf": [
         {
diff --git a/scripts/build.ts b/scripts/build.ts
index 3d1a883bbec..04c4aa2a14e 100644
--- a/scripts/build.ts
+++ b/scripts/build.ts
@@ -7,6 +7,7 @@ import { basename } from "node:path";
 import winston from "winston";
 import yargs from "yargs";
 import * as data from "../index.js";
+import { isOrdinaryFeatureData } from "../type-guards.js";
 import { validate } from "./validate.js";
 
 const logger = winston.createLogger({
@@ -68,6 +69,10 @@ function buildPackage() {
 
 function buildExtendedJSON() {
   for (const [id, featureData] of Object.entries(data.features)) {
+    if (!isOrdinaryFeatureData(featureData)) {
+      continue;
+    }
+
     if (
       Array.isArray(featureData.compat_features) &&
       featureData.compat_features.length &&
diff --git a/scripts/dist.ts b/scripts/dist.ts
index 209aa1d154a..1832f6a4b89 100644
--- a/scripts/dist.ts
+++ b/scripts/dist.ts
@@ -14,6 +14,7 @@ import { isDeepStrictEqual } from "node:util";
 import winston from "winston";
 import YAML, { Document, Scalar, YAMLSeq } from "yaml";
 import yargs from "yargs";
+import type { FeatureData, FeatureMovedData, FeatureSplitData } from "../types";
 
 const compat = new Compat();
 
@@ -181,6 +182,39 @@ function compareStatus(a: SupportStatus, b: SupportStatus) {
   return 0;
 }
 
+function toRedirectDist(
+  id: string,
+  source: FeatureMovedData | FeatureSplitData,
+): YAML.Document {
+  const dist = new Document({});
+
+  const comment = [
+    `Generated from: ${id}.yml`,
+    `This file intentionally left blank.`,
+    `Do not edit this file.`,
+  ];
+
+  const { kind } = source;
+  switch (kind) {
+    case "moved":
+      comment.push(
+        `The data for this feature has moved to ${source.redirect_target}.yml`,
+      );
+      break;
+    case "split":
+      comment.push(`The data for this feature has moved to:`);
+      comment.push(...source.redirect_targets.map((dest) => `  - ${dest}.yml`));
+      break;
+    default:
+      kind satisfies never;
+      throw new Error(`Unhandled feature kind ${kind}}`);
+  }
+
+  dist.commentBefore = comment.map((line) => ` ${line}`).join("\n");
+
+  return dist;
+}
+
 /**
  * Generate a dist YAML document from a feature definition YAML file path.
  *
@@ -192,6 +226,11 @@ function toDist(sourcePath: string): YAML.Document {
   const source = YAML.parse(fs.readFileSync(sourcePath, { encoding: "utf-8" }));
   const { name: id } = path.parse(sourcePath);
 
+  if ("redirect_target" in source || "redirect_targets" in source) {
+    return toRedirectDist(id, source);
+  }
+  source as Partial<FeatureData>;
+
   // Collect tagged compat features. A `compat_features` list in the source
   // takes precedence, but can be removed if it matches the tagged features.
   const taggedCompatFeatures = (tagsToFeatures.get(`web-features:${id}`) ?? [])
diff --git a/scripts/find-ranged-headline-statuses.ts b/scripts/find-ranged-headline-statuses.ts
index a5dabd2f0cd..e60f21efd00 100644
--- a/scripts/find-ranged-headline-statuses.ts
+++ b/scripts/find-ranged-headline-statuses.ts
@@ -1,7 +1,13 @@
 import { features } from "../index";
+import { isOrdinaryFeatureData } from "../type-guards";
 
 for (const [key, data] of Object.entries(features)) {
-  if ((data.status.baseline_low_date ?? "").includes("≤")) {
-    console.log(key);
+  if (isOrdinaryFeatureData(data)) {
+    if (
+      "status" in data &&
+      (data.status.baseline_low_date ?? "").includes("≤")
+    ) {
+      console.log(key);
+    }
   }
 }
diff --git a/scripts/inspect-feature.ts b/scripts/inspect-feature.ts
index 7c7c9e97f07..121dca044cf 100644
--- a/scripts/inspect-feature.ts
+++ b/scripts/inspect-feature.ts
@@ -3,6 +3,7 @@ import escapeHtml from "escape-html";
 import fs from "node:fs";
 import path from "node:path";
 import { fileURLToPath } from "node:url";
+import winston from "winston";
 import YAML from "yaml";
 import yargs from "yargs";
 import { features } from "..";
@@ -33,6 +34,15 @@ const argv = yargs(process.argv.slice(2))
     defaultDescription: "warn",
   }).argv as Args;
 
+const logger = winston.createLogger({
+  level: argv.verbose > 0 ? "debug" : "warn",
+  format: winston.format.combine(
+    winston.format.colorize(),
+    winston.format.simple(),
+  ),
+  transports: new winston.transports.Console(),
+});
+
 function main(): void {
   for (const filePath of argv.paths) {
     const { name, ext, dir } = path.parse(filePath);
@@ -45,6 +55,12 @@ function main(): void {
     if (!feature) {
       throw new Error(`No feature found for ID ${id}`);
     }
+    if (feature.kind === "moved" || feature.kind === "split") {
+      logger.warn(
+        `${id} is a ${feature.kind} feature. Did you mean to inspect this?`,
+      );
+      continue;
+    }
 
     const { compat_features } = feature;
 
diff --git a/scripts/specs.ts b/scripts/specs.ts
index a2372fc5e9e..c1e7284ff28 100644
--- a/scripts/specs.ts
+++ b/scripts/specs.ts
@@ -3,6 +3,7 @@ import assert from "node:assert/strict";
 import webSpecs from 'web-specs' with { type: 'json' };
 
 import { features } from '../index.js';
+import { isOrdinaryFeatureData } from "../type-guards.js";
 
 // Specs needs to be in "good standing". Nightly URLs are used if available,
 // otherwise the snapshot/versioned URL is used. See browser-specs/web-specs
@@ -195,6 +196,10 @@ for (const [allowedUrl, message] of defaultAllowlist) {
 }
 
 for (const [id, data] of Object.entries(features)) {
+    if (!isOrdinaryFeatureData(data)) {
+        continue;
+    }
+
     const specs = Array.isArray(data.spec) ? data.spec : [data.spec];
     for (const spec of specs) {
         let url: URL;
diff --git a/scripts/stats.ts b/scripts/stats.ts
index 1894c73ba96..404efe51ddf 100644
--- a/scripts/stats.ts
+++ b/scripts/stats.ts
@@ -2,6 +2,7 @@ import { Compat } from "compute-baseline/browser-compat-data";
 import { fileURLToPath } from "node:url";
 import yargs from "yargs";
 import { features } from "../index.js";
+import { isOrdinaryFeatureData } from "../type-guards.js";
 
 const argv = yargs(process.argv.slice(2))
   .scriptName("stats")
@@ -14,11 +15,20 @@ const argv = yargs(process.argv.slice(2))
   }).argv;
 
 export function stats(detailed: boolean = false) {
-  const featureCount = Object.keys(features).length;
+  const featureCount = Object.values(features).filter(
+    isOrdinaryFeatureData,
+  ).length;
 
   const keys = [];
   const doneKeys = Array.from(
-    new Set(Object.values(features).flatMap((f) => f.compat_features ?? [])),
+    new Set(
+      Object.values(features).flatMap((f) => {
+        if (isOrdinaryFeatureData(f)) {
+          return f.compat_features ?? [];
+        }
+        return [];
+      }),
+    ),
   );
   const toDoKeys = [];
 
@@ -35,6 +45,7 @@ export function stats(detailed: boolean = false) {
   }
 
   const featureSizes = Object.values(features)
+    .filter(isOrdinaryFeatureData)
     .map((feature) => (feature.compat_features ?? []).length)
     .sort((a, b) => a - b);
 
diff --git a/scripts/update-drafts.ts b/scripts/update-drafts.ts
index f3fac0babdf..ab84d708596 100644
--- a/scripts/update-drafts.ts
+++ b/scripts/update-drafts.ts
@@ -11,6 +11,7 @@ import { Document, parse } from "yaml";
 import yargs from "yargs";
 
 import { features } from "../index.js";
+import { isOrdinaryFeatureData } from "../type-guards.js";
 import { FeatureData } from "../types.js";
 
 type WebSpecsSpec = (typeof webSpecs)[number];
@@ -84,7 +85,7 @@ async function main() {
   // Build a map of used BCD keys to feature.
   const webFeatures = new Map<string, string>();
   Object.values(features).map((data) => {
-    if (data.compat_features) {
+    if (isOrdinaryFeatureData(data) && data.compat_features) {
       for (const compatFeature of data.compat_features) {
         webFeatures.set(compatFeature, data.name);
       }
@@ -261,9 +262,12 @@ async function main() {
   }
 
   // Clean up completed specs, even if they've been superseded
-  const assignedKeys = Object.values(features).flatMap(
-    (f) => f.compat_features ?? [],
-  );
+  const assignedKeys = Object.values(features).flatMap((f) => {
+    if (isOrdinaryFeatureData(f)) {
+      return f.compat_features ?? [];
+    }
+    return [];
+  });
   for (const spec of webSpecs) {
     const id = formatIdentifier(spec.shortname);
     const destination = `features/draft/spec/${id}.yml`;
diff --git a/type-guards.ts b/type-guards.ts
new file mode 100644
index 00000000000..806a88139d4
--- /dev/null
+++ b/type-guards.ts
@@ -0,0 +1,13 @@
+import type { FeatureData, FeatureMovedData, FeatureSplitData } from "./types";
+
+export function isOrdinaryFeatureData(x: unknown): x is FeatureData {
+  return typeof x === "object" && "kind" in x && x.kind === "feature";
+}
+
+export function isSplit(x: unknown): x is FeatureSplitData {
+  return typeof x === "object" && "kind" in x && x.kind === "split";
+}
+
+export function isMoved(x: unknown): x is FeatureMovedData {
+  return typeof x === "object" && "kind" in x && x.kind === "moved";
+}
diff --git a/types.quicktype.ts b/types.quicktype.ts
index a62d87701e3..abf8e3474c5 100644
--- a/types.quicktype.ts
+++ b/types.quicktype.ts
@@ -60,6 +60,10 @@ export interface Release {
 
 /**
  * A feature data entry
+ *
+ * A feature has permanently moved to exactly one other ID
+ *
+ * A feature has split into two or more other features
  */
 export interface FeatureData {
   /**
@@ -73,11 +77,11 @@ export interface FeatureData {
   /**
    * Short description of the feature, as a plain text string
    */
-  description: string;
+  description?: string;
   /**
    * Short description of the feature, as an HTML string
    */
-  description_html: string;
+  description_html?: string;
   /**
    * Whether developers are formally discouraged from using this feature
    */
@@ -86,10 +90,11 @@ export interface FeatureData {
    * Group identifier(s)
    */
   group?: string[] | string;
+  kind: Kind;
   /**
    * Short name
    */
-  name: string;
+  name?: string;
   /**
    * Snapshot identifier(s)
    */
@@ -97,12 +102,20 @@ export interface FeatureData {
   /**
    * Specification URL(s)
    */
-  spec: string[] | string;
+  spec?: string[] | string;
   /**
    * Whether a feature is considered a "Baseline" web platform feature and when it achieved
    * that status
    */
-  status: StatusHeadline;
+  status?: StatusHeadline;
+  /**
+   * The new ID for this feature
+   */
+  redirect_target?: string;
+  /**
+   * The new IDs for this feature
+   */
+  redirect_targets?: string[];
 }
 
 /**
@@ -120,6 +133,8 @@ export interface Discouraged {
   alternatives?: string[];
 }
 
+export type Kind = "feature" | "moved" | "split";
+
 /**
  * Whether a feature is considered a "Baseline" web platform feature and when it achieved
  * that status
diff --git a/types.ts b/types.ts
index a0cb96cb7d8..de0c7ad2fbe 100644
--- a/types.ts
+++ b/types.ts
@@ -10,6 +10,7 @@ import type {
   Browsers,
   Discouraged,
   GroupData,
+  Kind,
   FeatureData as QuicktypeMonolithicFeatureData,
   Status as QuicktypeStatus,
   StatusHeadline as QuicktypeStatusHeadline,
@@ -66,10 +67,12 @@ const goodSupportStatus: QuicktypeStatusHeadline | SupportStatus = {
 
 export interface WebFeaturesData
   extends Pick<QuicktypeWebFeaturesData, "browsers" | "groups" | "snapshots"> {
-  features: { [key: string]: FeatureData };
+  features: {
+    [key: string]: FeatureData | FeatureMovedData | FeatureSplitData;
+  };
 }
 
-export type FeatureData = Required<
+export type FeatureData = { kind: "feature" } & Required<
   Pick<
     QuicktypeMonolithicFeatureData,
     "description_html" | "description" | "name" | "spec" | "status"
@@ -83,6 +86,7 @@ export type FeatureData = Required<
   >;
 
 const goodFeatureData: FeatureData = {
+  kind: "feature",
   name: "Test",
   description: "Hi",
   description_html: "Hi",
@@ -93,4 +97,38 @@ const goodFeatureData: FeatureData = {
   },
 };
 
+type FeatureRedirectData = { kind: Exclude<Kind, "feature"> } & Required<
+  Pick<QuicktypeMonolithicFeatureData, "redirect_target" | "redirect_targets">
+>;
+
+export interface FeatureMovedData
+  extends Omit<FeatureRedirectData, "redirect_targets"> {
+  kind: "moved";
+}
+
+const goodFeatureMovedData: FeatureMovedData = {
+  kind: "moved",
+  redirect_target: "",
+};
+const badFeatureMovedData: FeatureMovedData = {
+  kind: "moved",
+  // @ts-expect-error
+  redirect_targets: ["", ""],
+};
+
+export interface FeatureSplitData
+  extends Omit<FeatureRedirectData, "redirect_target"> {
+  kind: "split";
+}
+
+const goodFeatureSplitData: FeatureSplitData = {
+  kind: "split",
+  redirect_targets: ["", ""],
+};
+const badFeatureSplitData: FeatureSplitData = {
+  kind: "split",
+  // @ts-expect-error
+  redirect_target: "",
+};
+
 export type BrowserIdentifier = keyof Browsers;