diff --git a/src/ol/proj/chprojection.js b/src/ol/proj/chprojection.js
index 50b5fd3818..901181af56 100644
--- a/src/ol/proj/chprojection.js
+++ b/src/ol/proj/chprojection.js
@@ -17,6 +17,7 @@ goog.require('ol.proj.Units');
  * @constructor
  * @extends {ol.proj.Projection}
  * @param {{code: string, extent: ol.Extent}} options Options.
+ * @todo api
  */
 ol.proj.CH = function(options) {
   goog.base(this, {
@@ -395,6 +396,7 @@ ol.proj.CH.prototype.getPointResolution = function(resolution, point) {
  * The EPSG:2056 projection, also known as LV95 (CH1903+).
  * @constructor
  * @extends {ol.proj.CH}
+ * @todo api
  */
 ol.proj.EPSG2056 = function() {
   goog.base(this, {
@@ -433,6 +435,7 @@ ol.proj.EPSG2056.add = function() {
  * The EPSG:21781 projection, also known as LV03 (CH1903).
  * @constructor
  * @extends {ol.proj.CH}
+ * @todo api
  */
 ol.proj.EPSG21781 = function() {
   goog.base(this, {
diff --git a/src/ol/proj/epsg3857projection.js b/src/ol/proj/epsg3857projection.js
index 7c7fb374d4..e811a42ecc 100644
--- a/src/ol/proj/epsg3857projection.js
+++ b/src/ol/proj/epsg3857projection.js
@@ -13,6 +13,7 @@ goog.require('ol.proj.Units');
  * @constructor
  * @extends {ol.proj.Projection}
  * @param {string} code Code.
+ * @todo api
  */
 ol.proj.EPSG3857 = function(code) {
   goog.base(this, {
diff --git a/src/ol/proj/epsg4326projection.js b/src/ol/proj/epsg4326projection.js
index 3f291ef5f1..c891790b14 100644
--- a/src/ol/proj/epsg4326projection.js
+++ b/src/ol/proj/epsg4326projection.js
@@ -11,6 +11,7 @@ goog.require('ol.proj.Units');
  * @extends {ol.proj.Projection}
  * @param {string} code Code.
  * @param {string=} opt_axisOrientation Axis orientation.
+ * @todo api
  */
 ol.proj.EPSG4326 = function(code, opt_axisOrientation) {
   goog.base(this, {