diff --git a/common/TrunkStable.bp b/common/TrunkStable.bp
index 772f79e..56938fc 100644
--- a/common/TrunkStable.bp
+++ b/common/TrunkStable.bp
@@ -19,3 +19,8 @@
     package: "com.android.net.flags",
     srcs: ["flags.aconfig"],
 }
+
+java_aconfig_library {
+    name: "connectivity_flags_aconfig_lib",
+    aconfig_declarations: "com.android.net.flags-aconfig",
+}
diff --git a/common/flags.aconfig b/common/flags.aconfig
index 4926503..cadc44f 100644
--- a/common/flags.aconfig
+++ b/common/flags.aconfig
@@ -6,3 +6,10 @@
   description: "NetworkActivityTracker tracks multiple networks including non default networks"
   bug: "267870186"
 }
+
+flag {
+  name: "forbidden_capability"
+  namespace: "android_core_networking"
+  description: "This flag controls the forbidden capability API"
+  bug: "302997505"
+}
diff --git a/framework/src/android/net/NetworkCapabilities.java b/framework/src/android/net/NetworkCapabilities.java
index 5d70857..74d50f8 100644
--- a/framework/src/android/net/NetworkCapabilities.java
+++ b/framework/src/android/net/NetworkCapabilities.java
@@ -29,6 +29,9 @@
 import android.annotation.SystemApi;
 import android.compat.annotation.UnsupportedAppUsage;
 import android.net.ConnectivityManager.NetworkCallback;
+// Can't be imported because aconfig tooling doesn't exist on udc-mainline-prod yet
+// See inner class Flags which mimics this for the time being
+// import android.net.flags.Flags;
 import android.os.Build;
 import android.os.Parcel;
 import android.os.Parcelable;
@@ -121,6 +124,14 @@
 public final class NetworkCapabilities implements Parcelable {
     private static final String TAG = "NetworkCapabilities";
 
+    // TODO : remove this class when udc-mainline-prod is abandoned and android.net.flags.Flags is
+    // available here
+    /** @hide */
+    public static class Flags {
+        static final String FLAG_FORBIDDEN_CAPABILITY =
+                "com.android.net.flags.forbidden_capability";
+    }
+
     /**
      * Mechanism to support redaction of fields in NetworkCapabilities that are guarded by specific
      * app permissions.
@@ -793,6 +804,10 @@
      * Adds the given capability to this {@code NetworkCapability} instance.
      * Note that when searching for a network to satisfy a request, all capabilities
      * requested must be satisfied.
+     * <p>
+     * If the capability was previously added to the list of forbidden capabilities (either
+     * by default or added using {@link #addForbiddenCapability(int)}), then it will be removed
+     * from the list of forbidden capabilities as well.
      *
      * @param capability the capability to be added.
      * @return This NetworkCapabilities instance, to facilitate chaining.
@@ -801,8 +816,7 @@
     public @NonNull NetworkCapabilities addCapability(@NetCapability int capability) {
         // If the given capability was previously added to the list of forbidden capabilities
         // then the capability will also be removed from the list of forbidden capabilities.
-        // TODO: Consider adding forbidden capabilities to the public API and mention this
-        // in the documentation.
+        // TODO: Add forbidden capabilities to the public API
         checkValidCapability(capability);
         mNetworkCapabilities |= 1L << capability;
         // remove from forbidden capability list
@@ -901,6 +915,8 @@
      * @return an array of forbidden capability values for this instance.
      * @hide
      */
+    @NonNull
+    // TODO : @FlaggedApi(Flags.FLAG_FORBIDDEN_CAPABILITY) and public
     public @NetCapability int[] getForbiddenCapabilities() {
         return BitUtils.unpackBits(mForbiddenNetworkCapabilities);
     }
@@ -1000,7 +1016,7 @@
     /**
      * Tests for the presence of a capability on this instance.
      *
-     * @param capability the capabilities to be tested for.
+     * @param capability the capability to be tested for.
      * @return {@code true} if set on this instance.
      */
     public boolean hasCapability(@NetCapability int capability) {
@@ -1008,8 +1024,15 @@
                 && ((mNetworkCapabilities & (1L << capability)) != 0);
     }
 
-    /** @hide */
+    /**
+     * Tests for the presence of a forbidden capability on this instance.
+     *
+     * @param capability the capability to be tested for.
+     * @return {@code true} if this capability is set forbidden on this instance.
+     * @hide
+     */
     @SystemApi(client = SystemApi.Client.MODULE_LIBRARIES)
+    // TODO : @FlaggedApi(Flags.FLAG_FORBIDDEN_CAPABILITY) and public
     public boolean hasForbiddenCapability(@NetCapability int capability) {
         return isValidCapability(capability)
                 && ((mForbiddenNetworkCapabilities & (1L << capability)) != 0);
@@ -2889,6 +2912,44 @@
         }
 
         /**
+         * Adds the given capability to the list of forbidden capabilities.
+         *
+         * A network with a capability will not match a {@link NetworkCapabilities} or
+         * {@link NetworkRequest} which has said capability set as forbidden. For example, if
+         * a request has NET_CAPABILITY_INTERNET in the list of forbidden capabilities, networks
+         * with NET_CAPABILITY_INTERNET will not match the request.
+         *
+         * If the capability was previously added to the list of required capabilities (for
+         * example, it was there by default or added using {@link #addCapability(int)} method), then
+         * it will be removed from the list of required capabilities as well.
+         *
+         * @param capability the capability
+         * @return this builder
+         * @hide
+         */
+        @NonNull
+        // TODO : @FlaggedApi(Flags.FLAG_FORBIDDEN_CAPABILITY) and public
+        public Builder addForbiddenCapability(@NetCapability final int capability) {
+            mCaps.addForbiddenCapability(capability);
+            return this;
+        }
+
+        /**
+         * Removes the given capability from the list of forbidden capabilities.
+         *
+         * @see #addForbiddenCapability(int)
+         * @param capability the capability
+         * @return this builder
+         * @hide
+         */
+        @NonNull
+        // TODO : @FlaggedApi(Flags.FLAG_FORBIDDEN_CAPABILITY) and public
+        public Builder removeForbiddenCapability(@NetCapability final int capability) {
+            mCaps.removeForbiddenCapability(capability);
+            return this;
+        }
+
+        /**
          * Adds the given enterprise capability identifier.
          * Note that when searching for a network to satisfy a request, all capabilities identifier
          * requested must be satisfied. Enterprise capability identifier is applicable only
diff --git a/framework/src/android/net/NetworkRequest.java b/framework/src/android/net/NetworkRequest.java
index 6c351d0..5cc9f1b 100644
--- a/framework/src/android/net/NetworkRequest.java
+++ b/framework/src/android/net/NetworkRequest.java
@@ -39,6 +39,8 @@
 import android.annotation.SuppressLint;
 import android.annotation.SystemApi;
 import android.compat.annotation.UnsupportedAppUsage;
+// TODO : replace with android.net.flags.Flags when aconfig is supported on udc-mainline-prod
+// import android.net.NetworkCapabilities.Flags;
 import android.net.NetworkCapabilities.NetCapability;
 import android.net.NetworkCapabilities.Transport;
 import android.os.Build;
@@ -408,6 +410,7 @@
         @NonNull
         @SuppressLint("MissingGetterMatchingBuilder")
         @SystemApi(client = SystemApi.Client.MODULE_LIBRARIES)
+        // TODO : @FlaggedApi(Flags.FLAG_FORBIDDEN_CAPABILITY) and public
         public Builder addForbiddenCapability(@NetworkCapabilities.NetCapability int capability) {
             mNetworkCapabilities.addForbiddenCapability(capability);
             return this;
@@ -424,6 +427,7 @@
         @NonNull
         @SuppressLint("BuilderSetStyle")
         @SystemApi(client = SystemApi.Client.MODULE_LIBRARIES)
+        // TODO : @FlaggedApi(Flags.FLAG_FORBIDDEN_CAPABILITY) and public
         public Builder removeForbiddenCapability(
                 @NetworkCapabilities.NetCapability int capability) {
             mNetworkCapabilities.removeForbiddenCapability(capability);
@@ -433,6 +437,7 @@
         /**
          * Completely clears all the {@code NetworkCapabilities} from this builder instance,
          * removing even the capabilities that are set by default when the object is constructed.
+         * Also removes any set forbidden capabilities.
          *
          * @return The builder to facilitate chaining.
          */
@@ -721,6 +726,7 @@
      * @hide
      */
     @SystemApi(client = SystemApi.Client.MODULE_LIBRARIES)
+    // TODO : @FlaggedApi(Flags.FLAG_FORBIDDEN_CAPABILITY) and public instead of @SystemApi
     public boolean hasForbiddenCapability(@NetCapability int capability) {
         return networkCapabilities.hasForbiddenCapability(capability);
     }
@@ -843,6 +849,7 @@
      */
     @NonNull
     @SystemApi(client = SystemApi.Client.MODULE_LIBRARIES)
+    // TODO : @FlaggedApi(Flags.FLAG_FORBIDDEN_CAPABILITY) and public instead of @SystemApi
     public @NetCapability int[] getForbiddenCapabilities() {
         // No need to make a defensive copy here as NC#getForbiddenCapabilities() already returns
         // a new array.
diff --git a/tests/cts/net/src/android/net/cts/NetworkRequestTest.java b/tests/cts/net/src/android/net/cts/NetworkRequestTest.java
index 637ed26..718ca6d 100644
--- a/tests/cts/net/src/android/net/cts/NetworkRequestTest.java
+++ b/tests/cts/net/src/android/net/cts/NetworkRequestTest.java
@@ -104,6 +104,23 @@
         verifyNoCapabilities(nr);
     }
 
+    @Test @IgnoreUpTo(Build.VERSION_CODES.R)
+    public void testForbiddenCapabilities() {
+        final NetworkRequest.Builder builder = new NetworkRequest.Builder();
+        builder.addForbiddenCapability(NET_CAPABILITY_MMS);
+        assertTrue(builder.build().hasForbiddenCapability(NET_CAPABILITY_MMS));
+        builder.removeForbiddenCapability(NET_CAPABILITY_MMS);
+        assertFalse(builder.build().hasCapability(NET_CAPABILITY_MMS));
+        builder.addCapability(NET_CAPABILITY_MMS);
+        assertFalse(builder.build().hasForbiddenCapability(NET_CAPABILITY_MMS));
+        assertTrue(builder.build().hasCapability(NET_CAPABILITY_MMS));
+        builder.addForbiddenCapability(NET_CAPABILITY_MMS);
+        assertTrue(builder.build().hasForbiddenCapability(NET_CAPABILITY_MMS));
+        assertFalse(builder.build().hasCapability(NET_CAPABILITY_MMS));
+        builder.clearCapabilities();
+        verifyNoCapabilities(builder.build());
+    }
+
     @Test @IgnoreUpTo(Build.VERSION_CODES.Q)
     public void testTemporarilyNotMeteredCapability() {
         assertTrue(new NetworkRequest.Builder()