diff --git a/plugin-api/.gitignore b/plugin-api/.gitignore
new file mode 100644
index 00000000000..ab956abf6f9
--- /dev/null
+++ b/plugin-api/.gitignore
@@ -0,0 +1 @@
+/eclipse-build/
diff --git a/plugin-api/pom.xml b/plugin-api/pom.xml
new file mode 100644
index 00000000000..e5943d9932f
--- /dev/null
+++ b/plugin-api/pom.xml
@@ -0,0 +1,67 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<project xmlns="http://maven.apache.org/POM/4.0.0"
+         xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
+         xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
+    <parent>
+        <artifactId>elasticsearch-license</artifactId>
+        <groupId>org.elasticsearch</groupId>
+        <version>2.0.0-SNAPSHOT</version>
+    </parent>
+    <modelVersion>4.0.0</modelVersion>
+
+    <artifactId>elasticsearch-license-plugin-api</artifactId>
+    <properties>
+        <license.basedir combine.self="override">${project.parent.basedir}</license.basedir>
+    </properties>
+
+
+    <dependencies>
+        <dependency>
+            <groupId>org.elasticsearch</groupId>
+            <artifactId>elasticsearch-license-licensor</artifactId>
+            <version>2.0.0-SNAPSHOT</version>
+            <scope>test</scope>
+        </dependency>
+        <dependency>
+            <groupId>org.elasticsearch</groupId>
+            <artifactId>elasticsearch-license-core</artifactId>
+            <version>2.0.0-SNAPSHOT</version>
+            <scope>compile</scope>
+        </dependency>
+    </dependencies>
+
+    <build>
+        <resources>
+            <resource>
+                <directory>src/main/resources</directory>
+                <filtering>true</filtering>
+        </resource>
+        </resources>
+
+        <plugins>
+
+<!--            <plugin>
+                <groupId>org.apache.maven.plugins</groupId>
+                <artifactId>maven-jar-plugin</artifactId>
+                <executions>
+                    <execution>
+                        <id>for-plugin</id>
+                        <phase>prepare-package</phase>
+                        <goals>
+                            <goal>jar</goal>
+                        </goals>
+                    </execution>
+                </executions>
+            </plugin>-->
+
+            <plugin>
+                <groupId>com.carrotsearch.randomizedtesting</groupId>
+                <artifactId>junit4-maven-plugin</artifactId>
+                <configuration>
+                <skipTests>true</skipTests>
+                </configuration>
+            </plugin>
+        </plugins>
+
+    </build>
+</project>
\ No newline at end of file
diff --git a/plugin-api/src/main/java/org/elasticsearch/license/plugin/LicenseVersion.java b/plugin-api/src/main/java/org/elasticsearch/license/plugin/LicenseVersion.java
new file mode 100644
index 00000000000..4e2cad0d5cd
--- /dev/null
+++ b/plugin-api/src/main/java/org/elasticsearch/license/plugin/LicenseVersion.java
@@ -0,0 +1,191 @@
+/*
+ * Copyright Elasticsearch B.V. and/or licensed to Elasticsearch B.V. under one
+ * or more contributor license agreements. Licensed under the Elastic License;
+ * you may not use this file except in compliance with the Elastic License.
+ */
+package org.elasticsearch.license.plugin;
+
+import org.elasticsearch.Version;
+import org.elasticsearch.common.Nullable;
+import org.elasticsearch.common.Strings;
+import org.elasticsearch.common.io.stream.StreamInput;
+import org.elasticsearch.common.io.stream.StreamOutput;
+import org.elasticsearch.license.core.License;
+
+import java.io.IOException;
+import java.io.Serializable;
+
+@SuppressWarnings("deprecation")
+public class LicenseVersion implements Serializable {
+
+    // The logic for ID is: XXYYZZAA, where XX is major version, YY is minor version, ZZ is revision, and AA is Beta/RC indicator
+    // AA values below 50 are beta builds, and below 99 are RC builds, with 99 indicating a release
+    // the (internal) format of the id is there so we can easily do after/before checks on the id
+
+    public static final int V_1_0_0_ID = /*00*/1000099;
+    public static final int V_2_0_0_ID = /*00*/2000099;
+    public static final LicenseVersion V_1_0_0 = new LicenseVersion(V_1_0_0_ID, false, License.VERSION_START, Version.V_1_4_0_Beta1);
+    public static final LicenseVersion V_2_0_0 = new LicenseVersion(V_2_0_0_ID, true, License.VERSION_START, Version.V_2_0_0);
+
+    public static final LicenseVersion CURRENT = V_2_0_0;
+
+    public static LicenseVersion readVersion(StreamInput in) throws IOException {
+        return fromId(in.readVInt());
+    }
+
+    public static LicenseVersion fromId(int id) {
+        switch (id) {
+            case V_1_0_0_ID:
+                return V_1_0_0;
+
+            default:
+                return new LicenseVersion(id, null, License.VERSION_CURRENT, Version.CURRENT);
+        }
+    }
+
+    public static void writeVersion(LicenseVersion version, StreamOutput out) throws IOException {
+        out.writeVInt(version.id);
+    }
+
+    /**
+     * Returns the smallest version between the 2.
+     */
+    public static LicenseVersion smallest(LicenseVersion version1, LicenseVersion version2) {
+        return version1.id < version2.id ? version1 : version2;
+    }
+
+    /**
+     * Returns the version given its string representation, current version if the argument is null or empty
+     */
+    public static LicenseVersion fromString(String version) {
+        if (!Strings.hasLength(version)) {
+            return LicenseVersion.CURRENT;
+        }
+
+        String[] parts = version.split("\\.");
+        if (parts.length < 3 || parts.length > 4) {
+            throw new IllegalArgumentException("the version needs to contain major, minor and revision, and optionally the build");
+        }
+
+        try {
+            //we reverse the version id calculation based on some assumption as we can't reliably reverse the modulo
+            int major = Integer.parseInt(parts[0]) * 1000000;
+            int minor = Integer.parseInt(parts[1]) * 10000;
+            int revision = Integer.parseInt(parts[2]) * 100;
+
+            int build = 99;
+            if (parts.length == 4) {
+                String buildStr = parts[3];
+                if (buildStr.startsWith("Beta")) {
+                    build = Integer.parseInt(buildStr.substring(4));
+                }
+                if (buildStr.startsWith("RC")) {
+                    build = Integer.parseInt(buildStr.substring(2)) + 50;
+                }
+            }
+
+            return fromId(major + minor + revision + build);
+
+        } catch(NumberFormatException e) {
+            throw new IllegalArgumentException("unable to parse version " + version, e);
+        }
+    }
+
+    public final int id;
+    public final byte major;
+    public final byte minor;
+    public final byte revision;
+    public final byte build;
+    public final Boolean snapshot;
+    public final int minSignatureVersion;
+    public final Version minEsCompatibilityVersion;
+
+    LicenseVersion(int id, @Nullable Boolean snapshot, int minSignatureVersion, Version minEsCompatibilityVersion) {
+        this.id = id;
+        this.major = (byte) ((id / 1000000) % 100);
+        this.minor = (byte) ((id / 10000) % 100);
+        this.revision = (byte) ((id / 100) % 100);
+        this.build = (byte) (id % 100);
+        this.snapshot = snapshot;
+        this.minSignatureVersion = minSignatureVersion;
+        this.minEsCompatibilityVersion = minEsCompatibilityVersion;
+    }
+
+    public boolean snapshot() {
+        return snapshot != null && snapshot;
+    }
+
+    public boolean after(LicenseVersion version) {
+        return version.id < id;
+    }
+
+    public boolean before(LicenseVersion version) {
+        return version.id > id;
+    }
+
+    /**
+     * Returns the minimum compatible version based on the current
+     * version. Ie a node needs to have at least the return version in order
+     * to communicate with a node running the current version. The returned version
+     * is in most of the cases the smallest major version release unless the current version
+     * is a beta or RC release then the version itself is returned.
+     */
+    public LicenseVersion minimumCompatibilityVersion() {
+        return LicenseVersion.smallest(this, fromId(major * 1000000 + 99));
+    }
+
+    /**
+     * @return  The minimum elasticsearch version this license version is compatible with.
+     */
+    public Version minimumEsCompatiblityVersion() {
+        return minEsCompatibilityVersion;
+    }
+
+    /**
+     * @return The minimum license signature version this license plugin is compatible with.
+     */
+    public int minimumSignatureVersion() {
+        return minSignatureVersion;
+    }
+
+    /**
+     * Just the version number (without -SNAPSHOT if snapshot).
+     */
+    public String number() {
+        StringBuilder sb = new StringBuilder();
+        sb.append(major).append('.').append(minor).append('.').append(revision);
+        if (build < 50) {
+            sb.append(".Beta").append(build);
+        } else if (build < 99) {
+            sb.append(".RC").append(build - 50);
+        }
+        return sb.toString();
+    }
+
+    @Override
+    public String toString() {
+        StringBuilder sb = new StringBuilder();
+        sb.append(number());
+        if (snapshot()) {
+            sb.append("-SNAPSHOT");
+        }
+        return sb.toString();
+    }
+
+    @Override
+    public boolean equals(Object o) {
+        if (this == o) return true;
+        if (o == null || getClass() != o.getClass()) return false;
+
+        LicenseVersion that = (LicenseVersion) o;
+
+        if (id != that.id) return false;
+
+        return true;
+    }
+
+    @Override
+    public int hashCode() {
+        return id;
+    }
+}
diff --git a/plugin-api/src/main/java/org/elasticsearch/license/plugin/core/LicenseExpiredException.java b/plugin-api/src/main/java/org/elasticsearch/license/plugin/core/LicenseExpiredException.java
new file mode 100644
index 00000000000..4fbbe351804
--- /dev/null
+++ b/plugin-api/src/main/java/org/elasticsearch/license/plugin/core/LicenseExpiredException.java
@@ -0,0 +1,31 @@
+/*
+ * Copyright Elasticsearch B.V. and/or licensed to Elasticsearch B.V. under one
+ * or more contributor license agreements. Licensed under the Elastic License;
+ * you may not use this file except in compliance with the Elastic License.
+ */
+package org.elasticsearch.license.plugin.core;
+
+import org.elasticsearch.ElasticsearchException;
+import org.elasticsearch.rest.RestStatus;
+
+/**
+ * Exception to be thrown when a feature action requires a valid license
+ */
+public class LicenseExpiredException extends ElasticsearchException {
+
+    private final String feature;
+
+    public LicenseExpiredException(String feature) {
+        super("license expired for feature [" + feature + "]");
+        this.feature = feature;
+    }
+
+    @Override
+    public RestStatus status() {
+        return RestStatus.UNAUTHORIZED;
+    }
+
+    public String feature() {
+        return feature;
+    }
+}
diff --git a/plugin-api/src/main/java/org/elasticsearch/license/plugin/core/LicensesClientService.java b/plugin-api/src/main/java/org/elasticsearch/license/plugin/core/LicensesClientService.java
new file mode 100644
index 00000000000..548e87d72ea
--- /dev/null
+++ b/plugin-api/src/main/java/org/elasticsearch/license/plugin/core/LicensesClientService.java
@@ -0,0 +1,164 @@
+/*
+ * Copyright Elasticsearch B.V. and/or licensed to Elasticsearch B.V. under one
+ * or more contributor license agreements. Licensed under the Elastic License;
+ * you may not use this file except in compliance with the Elastic License.
+ */
+package org.elasticsearch.license.plugin.core;
+
+import org.elasticsearch.common.unit.TimeValue;
+import org.elasticsearch.license.core.License;
+
+import java.util.Collection;
+
+
+//@ImplementedBy(LicensesService.class)
+public interface LicensesClientService {
+
+    public interface Listener {
+
+        /**
+         * Called to enable a feature
+         */
+        public void onEnabled(License license);
+
+        /**
+         * Called to disable a feature
+         */
+        public void onDisabled(License license);
+
+    }
+
+    /**
+     * Registers a feature for licensing
+     *
+     * @param feature             - name of the feature to register (must be in sync with license Generator feature name)
+     * @param trialLicenseOptions - Trial license specification used to generate a one-time trial license for the feature;
+     *                            use <code>null</code> if no trial license should be generated for the feature
+     * @param expirationCallbacks - A collection of Pre and/or Post expiration callbacks
+     * @param listener            - used to notify on feature enable/disable
+     */
+    void register(String feature, TrialLicenseOptions trialLicenseOptions, Collection<ExpirationCallback> expirationCallbacks, Listener listener);
+    
+    public static class TrialLicenseOptions {
+        final TimeValue duration;
+        final int maxNodes;
+
+        public TrialLicenseOptions(TimeValue duration, int maxNodes) {
+            this.duration = duration;
+            this.maxNodes = maxNodes;
+        }
+    }
+    
+
+    public static interface LicenseCallback {
+        void on(License license, ExpirationStatus status);
+    }
+
+    public static abstract class ExpirationCallback implements LicenseCallback {
+
+        public enum Orientation { PRE, POST }
+
+        public static abstract class Pre extends ExpirationCallback {
+
+            /**
+             * Callback schedule prior to license expiry
+             *
+             * @param min latest relative time to execute before license expiry
+             * @param max earliest relative time to execute before license expiry
+             * @param frequency interval between execution
+             */
+            public Pre(TimeValue min, TimeValue max, TimeValue frequency) {
+                super(Orientation.PRE, min, max, frequency);
+            }
+
+            @Override
+            public boolean matches(long expirationDate, long now) {
+                long expiryDuration = expirationDate - now;
+                if (expiryDuration > 0l) {
+                    if (expiryDuration <= max().getMillis()) {
+                        return expiryDuration >= min().getMillis();
+                    }
+                }
+                return false;
+            }
+        }
+
+        public static abstract class Post extends ExpirationCallback {
+
+            /**
+             * Callback schedule after license expiry
+             *
+             * @param min earliest relative time to execute after license expiry
+             * @param max latest relative time to execute after license expiry
+             * @param frequency interval between execution
+             */
+            public Post(TimeValue min, TimeValue max, TimeValue frequency) {
+                super(Orientation.POST, min, max, frequency);
+            }
+
+            @Override
+            public boolean matches(long expirationDate, long now) {
+                long postExpiryDuration = now - expirationDate;
+                if (postExpiryDuration > 0l) {
+                    if (postExpiryDuration <= max().getMillis()) {
+                        return postExpiryDuration >= min().getMillis();
+                    }
+                }
+                return false;
+            }
+        }
+
+        private final Orientation orientation;
+        private final TimeValue min;
+        private final TimeValue max;
+        private final TimeValue frequency;
+
+        private ExpirationCallback(Orientation orientation, TimeValue min, TimeValue max, TimeValue frequency) {
+            this.orientation = orientation;
+            this.min = (min == null) ? TimeValue.timeValueMillis(0) : min;
+            this.max = (max == null) ? TimeValue.timeValueMillis(Long.MAX_VALUE) : max;
+            this.frequency = frequency;
+            if (frequency == null) {
+                throw new IllegalArgumentException("frequency can not be null");
+            }
+        }
+
+        public Orientation orientation() {
+            return orientation;
+        }
+
+        public TimeValue min() {
+            return min;
+        }
+
+        public TimeValue max() {
+            return max;
+        }
+
+        public TimeValue frequency() {
+            return frequency;
+        }
+
+        public abstract boolean matches(long expirationDate, long now);
+    }
+    
+    public static class ExpirationStatus {
+        private final boolean expired;
+        private final TimeValue time;
+
+        ExpirationStatus(boolean expired, TimeValue time) {
+            this.expired = expired;
+            this.time = time;
+        }
+
+        public boolean expired() {
+            return expired;
+        }
+
+        public TimeValue time() {
+            return time;
+        }
+    }
+
+
+}
diff --git a/plugin/.gitignore b/plugin/.gitignore
new file mode 100644
index 00000000000..ab956abf6f9
--- /dev/null
+++ b/plugin/.gitignore
@@ -0,0 +1 @@
+/eclipse-build/
diff --git a/plugin/pom.xml b/plugin/pom.xml
index ba579d18649..9ba064ca882 100644
--- a/plugin/pom.xml
+++ b/plugin/pom.xml
@@ -12,7 +12,8 @@
     <artifactId>elasticsearch-license-plugin</artifactId>
 
     <properties>
-        <!-- TODO: do we want to always enforce non-default keys -->
+        <!-- TODO: do we want to always enforce non-default keys
+         -->
         <keys.path>${basedir}/src/test/resources</keys.path>
         <license.basedir combine.self="override">${project.parent.basedir}</license.basedir>
     </properties>
@@ -30,6 +31,12 @@
             <version>2.0.0-SNAPSHOT</version>
             <scope>compile</scope>
         </dependency>
+        <dependency>
+            <groupId>org.elasticsearch</groupId>
+            <artifactId>elasticsearch-license-plugin-api</artifactId>
+            <version>2.0.0-SNAPSHOT</version>
+            <scope>compile</scope>
+        </dependency>
     </dependencies>
 
     <build>
diff --git a/plugin/src/main/java/org/elasticsearch/license/plugin/LicenseModule.java b/plugin/src/main/java/org/elasticsearch/license/plugin/LicenseModule.java
index dc9c4df64b3..4ec46ec33f0 100644
--- a/plugin/src/main/java/org/elasticsearch/license/plugin/LicenseModule.java
+++ b/plugin/src/main/java/org/elasticsearch/license/plugin/LicenseModule.java
@@ -8,6 +8,7 @@ package org.elasticsearch.license.plugin;
 import org.elasticsearch.common.inject.AbstractModule;
 import org.elasticsearch.common.inject.Scopes;
 import org.elasticsearch.license.core.LicenseVerifier;
+import org.elasticsearch.license.plugin.core.LicensesClientService;
 import org.elasticsearch.license.plugin.core.LicensesService;
 
 public class LicenseModule extends AbstractModule {
@@ -15,5 +16,6 @@ public class LicenseModule extends AbstractModule {
     protected void configure() {
         bind(LicenseVerifier.class).in(Scopes.SINGLETON);
         bind(LicensesService.class).in(Scopes.SINGLETON);
+        bind(LicensesClientService.class).to(LicensesService.class).in(Scopes.SINGLETON);
     }
 }
diff --git a/plugin/src/main/java/org/elasticsearch/license/plugin/core/LicensesClientService.java b/plugin/src/main/java/org/elasticsearch/license/plugin/core/LicensesClientService.java
deleted file mode 100644
index eb289cdb0e4..00000000000
--- a/plugin/src/main/java/org/elasticsearch/license/plugin/core/LicensesClientService.java
+++ /dev/null
@@ -1,43 +0,0 @@
-/*
- * Copyright Elasticsearch B.V. and/or licensed to Elasticsearch B.V. under one
- * or more contributor license agreements. Licensed under the Elastic License;
- * you may not use this file except in compliance with the Elastic License.
- */
-package org.elasticsearch.license.plugin.core;
-
-import org.elasticsearch.common.inject.ImplementedBy;
-import org.elasticsearch.license.core.License;
-
-import java.util.Collection;
-
-import static org.elasticsearch.license.plugin.core.LicensesService.*;
-import static org.elasticsearch.license.plugin.core.LicensesService.TrialLicenseOptions;
-
-@ImplementedBy(LicensesService.class)
-public interface LicensesClientService {
-
-    public interface Listener {
-
-        /**
-         * Called to enable a feature
-         */
-        public void onEnabled(License license);
-
-        /**
-         * Called to disable a feature
-         */
-        public void onDisabled(License license);
-
-    }
-
-    /**
-     * Registers a feature for licensing
-     *
-     * @param feature             - name of the feature to register (must be in sync with license Generator feature name)
-     * @param trialLicenseOptions - Trial license specification used to generate a one-time trial license for the feature;
-     *                            use <code>null</code> if no trial license should be generated for the feature
-     * @param expirationCallbacks - A collection of Pre and/or Post expiration callbacks
-     * @param listener            - used to notify on feature enable/disable
-     */
-    void register(String feature, TrialLicenseOptions trialLicenseOptions, Collection<ExpirationCallback> expirationCallbacks, Listener listener);
-}
diff --git a/plugin/src/main/java/org/elasticsearch/license/plugin/core/LicensesService.java b/plugin/src/main/java/org/elasticsearch/license/plugin/core/LicensesService.java
index 70c1d7e306b..ba638ab83bd 100644
--- a/plugin/src/main/java/org/elasticsearch/license/plugin/core/LicensesService.java
+++ b/plugin/src/main/java/org/elasticsearch/license/plugin/core/LicensesService.java
@@ -741,125 +741,8 @@ public class LicensesService extends AbstractLifecycleComponent<LicensesService>
         }
     }
 
-    public static class TrialLicenseOptions {
-        final TimeValue duration;
-        final int maxNodes;
 
-        public TrialLicenseOptions(TimeValue duration, int maxNodes) {
-            this.duration = duration;
-            this.maxNodes = maxNodes;
-        }
-    }
 
-    public static class ExpirationStatus {
-        private final boolean expired;
-        private final TimeValue time;
-
-        private ExpirationStatus(boolean expired, TimeValue time) {
-            this.expired = expired;
-            this.time = time;
-        }
-
-        public boolean expired() {
-            return expired;
-        }
-
-        public TimeValue time() {
-            return time;
-        }
-    }
-
-    public static interface LicenseCallback {
-        void on(License license, ExpirationStatus status);
-    }
-
-    public static abstract class ExpirationCallback implements LicenseCallback {
-
-        public enum Orientation { PRE, POST }
-
-        public static abstract class Pre extends ExpirationCallback {
-
-            /**
-             * Callback schedule prior to license expiry
-             *
-             * @param min latest relative time to execute before license expiry
-             * @param max earliest relative time to execute before license expiry
-             * @param frequency interval between execution
-             */
-            public Pre(TimeValue min, TimeValue max, TimeValue frequency) {
-                super(Orientation.PRE, min, max, frequency);
-            }
-
-            @Override
-            public boolean matches(long expirationDate, long now) {
-                long expiryDuration = expirationDate - now;
-                if (expiryDuration > 0l) {
-                    if (expiryDuration <= max().getMillis()) {
-                        return expiryDuration >= min().getMillis();
-                    }
-                }
-                return false;
-            }
-        }
-
-        public static abstract class Post extends ExpirationCallback {
-
-            /**
-             * Callback schedule after license expiry
-             *
-             * @param min earliest relative time to execute after license expiry
-             * @param max latest relative time to execute after license expiry
-             * @param frequency interval between execution
-             */
-            public Post(TimeValue min, TimeValue max, TimeValue frequency) {
-                super(Orientation.POST, min, max, frequency);
-            }
-
-            @Override
-            public boolean matches(long expirationDate, long now) {
-                long postExpiryDuration = now - expirationDate;
-                if (postExpiryDuration > 0l) {
-                    if (postExpiryDuration <= max().getMillis()) {
-                        return postExpiryDuration >= min().getMillis();
-                    }
-                }
-                return false;
-            }
-        }
-
-        private final Orientation orientation;
-        private final TimeValue min;
-        private final TimeValue max;
-        private final TimeValue frequency;
-
-        private ExpirationCallback(Orientation orientation, TimeValue min, TimeValue max, TimeValue frequency) {
-            this.orientation = orientation;
-            this.min = (min == null) ? TimeValue.timeValueMillis(0) : min;
-            this.max = (max == null) ? TimeValue.timeValueMillis(Long.MAX_VALUE) : max;
-            this.frequency = frequency;
-            if (frequency == null) {
-                throw new IllegalArgumentException("frequency can not be null");
-            }
-        }
-
-        public Orientation orientation() {
-            return orientation;
-        }
-
-        public TimeValue min() {
-            return min;
-        }
-
-        public TimeValue max() {
-            return max;
-        }
-
-        public TimeValue frequency() {
-            return frequency;
-        }
-
-        public abstract boolean matches(long expirationDate, long now);
-    }
 
     /**
      * Stores configuration and listener for a feature
@@ -993,6 +876,7 @@ public class LicensesService extends AbstractLifecycleComponent<LicensesService>
             }
         }
 
+        @Override
         public String toString() {
             return "(feature: " + feature + ", enabled: " + enabled + ")";
         }
diff --git a/pom.xml b/pom.xml
index b48a978ed53..d1884dd5614 100644
--- a/pom.xml
+++ b/pom.xml
@@ -19,6 +19,7 @@
         <module>core</module>
         <module>licensor</module>
         <module>plugin</module>
+        <module>plugin-api</module>
     </modules>
 
     <properties>