diff --git a/src/main/java/envoy/server/data/Contact.java b/src/main/java/envoy/server/data/Contact.java
index c9700d5..b6bc402 100644
--- a/src/main/java/envoy/server/data/Contact.java
+++ b/src/main/java/envoy/server/data/Contact.java
@@ -1,8 +1,19 @@
 package envoy.server.data;
 
+import java.util.Date;
 import java.util.Set;
 
-import javax.persistence.*;
+import javax.persistence.CascadeType;
+import javax.persistence.Entity;
+import javax.persistence.FetchType;
+import javax.persistence.GeneratedValue;
+import javax.persistence.Id;
+import javax.persistence.Inheritance;
+import javax.persistence.InheritanceType;
+import javax.persistence.ManyToMany;
+import javax.persistence.Table;
+import javax.persistence.Temporal;
+import javax.persistence.TemporalType;
 
 /**
  * This class acts as a superclass for all contacts, being {@link User}s and
@@ -26,6 +37,9 @@ public abstract class Contact {
 	protected long		id;
 	protected String	name;
 
+	@Temporal(TemporalType.TIMESTAMP)
+	private Date creationDate;
+
 	@ManyToMany(cascade = CascadeType.ALL, fetch = FetchType.EAGER)
 	protected Set<Contact> contacts;
 
@@ -86,6 +100,18 @@ public abstract class Contact {
 	 */
 	public void setContacts(Set<Contact> contacts) { this.contacts = contacts; }
 
+	/**
+	 * @return the creationDate
+	 * @since Envoy Server Standalone v0.1-beta
+	 */
+	public Date getCreationDate() { return creationDate; }
+
+	/**
+	 * @param creationDate the creationDate to set
+	 * @since Envoy Server Standalone v0.1-beta
+	 */
+	public void setCreationDate(Date creationDate) { this.creationDate = creationDate; }
+
 	/**
 	 * {@inheritDoc}
 	 */
diff --git a/src/main/java/envoy/server/data/Group.java b/src/main/java/envoy/server/data/Group.java
index 688ad4c..5f3be22 100644
--- a/src/main/java/envoy/server/data/Group.java
+++ b/src/main/java/envoy/server/data/Group.java
@@ -3,6 +3,7 @@ package envoy.server.data;
 import java.util.stream.Collectors;
 
 import javax.persistence.Entity;
+import javax.persistence.NamedQueries;
 import javax.persistence.NamedQuery;
 import javax.persistence.Table;
 
@@ -19,18 +20,31 @@ import javax.persistence.Table;
  */
 @Entity
 @Table(name = "groups")
-@NamedQuery(
-	name = Group.findByName,
-	query = "SELECT g FROM Group g WHERE g.name = :name"
-)
+@NamedQueries({
+	@NamedQuery(
+		name = Group.findByName,
+		query = "SELECT g FROM Group g WHERE g.name = :name"
+	),
+	@NamedQuery(
+		name = Group.findPendingGroups,
+		query = "SELECT g FROM Group g WHERE g.creationDate > :lastSeen AND :user MEMBER OF g.contacts"
+	)
+})
 public class Group extends Contact {
 
 	/**
-	 * Named query retrieving a group by name (parameter {@code :name}.
+	 * Named query retrieving a group by name (parameter {@code :name}).
 	 * 
 	 * @since Envoy Server Standalone v0.1-beta
 	 */
 	public static final String findByName = "Group.findByName";
+	
+	/**
+	 * Named query retrieving all pending groups for a specific user (parameter {@code :user}, {@code :lastSeen}).
+	 * 
+	 * @since Envoy Server Standalone v0.1-beta
+	 */
+	public static final String findPendingGroups = "Group.findPendingGroups";
 
 	/**
 	 * {@inheritDoc}