diff --git a/externs/olx.js b/externs/olx.js
index 72e1408807..b65465bfc2 100644
--- a/externs/olx.js
+++ b/externs/olx.js
@@ -5,52 +5,6 @@
 let olx;
 
 
-/**
- * @typedef {{defaultDataProjection: ol.ProjectionLike,
- *     geometryName: (string|undefined),
- *     extractGeometryName: (boolean|undefined),
- *     featureProjection: ol.ProjectionLike}}
- */
-olx.format.GeoJSONOptions;
-
-
-/**
- * Default data projection. Default is `EPSG:4326`.
- * @type {ol.ProjectionLike}
- * @api
- */
-olx.format.GeoJSONOptions.prototype.defaultDataProjection;
-
-
-/**
- * Projection for features read or written by the format.  Options passed to
- * read or write methods will take precedence.
- * @type {ol.ProjectionLike}
- * @api
- */
-olx.format.GeoJSONOptions.prototype.featureProjection;
-
-
-/**
- * Geometry name to use when creating features.
- * @type {string|undefined}
- * @api
- */
-olx.format.GeoJSONOptions.prototype.geometryName;
-
-
-/**
- * Certain GeoJSON providers include the geometry_name field in the feature
- * geoJSON. If set to `true` the geoJSON reader will look for that field to
- * set the geometry name. If both this field is set to `true` and a
- * `geometryName` is provided, the `geometryName` will take precedence.
- * Default is `false`.
- * @type {boolean|undefined}
- * @api
- */
-olx.format.GeoJSONOptions.prototype.extractGeometryName;
-
-
 /**
  * @typedef {{geometryName: (string|undefined)}}
  */
diff --git a/externs/xol.js b/externs/xol.js
index b7d8186602..b37b8c250f 100644
--- a/externs/xol.js
+++ b/externs/xol.js
@@ -1,17 +1,4 @@
 
-/**
- * @typedef {Object} format_GeoJSONOptions
- * @property {ol.ProjectionLike} defaultDataProjection Default data projection. Default is `EPSG:4326`.
- * @property {ol.ProjectionLike} featureProjection Projection for features read or written by the format.  Options passed to
- * read or write methods will take precedence.
- * @property {string|undefined} geometryName Geometry name to use when creating features.
- * @property {boolean|undefined} extractGeometryName Certain GeoJSON providers include the geometry_name field in the feature
- * geoJSON. If set to `true` the geoJSON reader will look for that field to
- * set the geometry name. If both this field is set to `true` and a
- * `geometryName` is provided, the `geometryName` will take precedence.
- * Default is `false`.
- */
-
 
 /**
  * @typedef {Object} format_EsriJSONOptions
diff --git a/src/ol/format/GeoJSON.js b/src/ol/format/GeoJSON.js
index 28e98919ff..a1ff628aac 100644
--- a/src/ol/format/GeoJSON.js
+++ b/src/ol/format/GeoJSON.js
@@ -19,13 +19,29 @@ import Polygon from '../geom/Polygon.js';
 import {assign, isEmpty} from '../obj.js';
 import {get as getProjection} from '../proj.js';
 
+
+/**
+ * @typedef {Object} Options
+ * @property {ol.ProjectionLike} defaultDataProjection Default data projection.
+ * Default is `EPSG:4326`.
+ * @property {ol.ProjectionLike} featureProjection Projection for features read or
+ * written by the format.  Options passed to read or write methods will take precedence.
+ * @property {string|undefined} geometryName Geometry name to use when creating features.
+ * @property {boolean|undefined} extractGeometryName Certain GeoJSON providers include
+ * the geometry_name field in the feature GeoJSON. If set to `true` the GeoJSON reader
+ * will look for that field to set the geometry name. If both this field is set to `true`
+ * and a `geometryName` is provided, the `geometryName` will take precedence.
+ * Default is `false`.
+ */
+
+
 /**
  * @classdesc
  * Feature format for reading and writing data in the GeoJSON format.
  *
  * @constructor
  * @extends {ol.format.JSONFeature}
- * @param {olx.format.GeoJSONOptions=} opt_options Options.
+ * @param {module:ol/format/GeoJSON~Options=} opt_options Options.
  * @api
  */
 const GeoJSON = function(opt_options) {