diff --git a/migrations/10_update_project_tokens.js b/migrations/10_update_project_tokens.js
new file mode 100644
index 0000000000..57095308f8
--- /dev/null
+++ b/migrations/10_update_project_tokens.js
@@ -0,0 +1,109 @@
+const Settings = require('settings-sharelatex')
+const Async = require('async')
+const mongojs = require('mongojs')
+const db = mongojs(Settings.mongo.url, ['users'])
+
+const indexKeys = { 'tokens.readAndWritePrefix': 1 }
+const indexOpts = {
+  unique: true,
+  partialFilterExpression: {
+    'tokens.readAndWritePrefix': { $exists: true }
+  },
+  background: true
+}
+
+// Index on Prefix
+const addReadAndWritePrefixIndex = (db, callback) => {
+  db.projects.ensureIndex(indexKeys, indexOpts, callback)
+}
+
+const removeReadAndWritePrefixIndex = (db, callback) => {
+  db.projects.dropIndex(indexKeys, callback)
+}
+
+// Extract prefix data
+const extractPrefix = (db, callback) => {
+  db.projects.find(
+    {
+      'tokens.readAndWrite': { $exists: true },
+      'tokens.readAndWritePrefix': { $exists: false }
+    },
+    { tokens: 1 },
+    (err, projects) => {
+      if (err) {
+        return callback(err)
+      }
+      console.log(`>> Updating ${projects.length} projects`)
+      Async.eachLimit(
+        projects,
+        5,
+        (project, cb) => {
+          const rwToken = project.tokens.readAndWrite
+          const prefixMatch = rwToken.match(/^(\d+).*$/)
+          if (!prefixMatch) {
+            const err = new Error(
+              `no prefix on token: ${project._id}, ${rwToken}`
+            )
+            console.log(`>> Error, ${err.message}`)
+            return cb(err)
+          }
+          db.projects.update(
+            { _id: project._id },
+            { $set: { 'tokens.readAndWritePrefix': prefixMatch[1] } },
+            cb
+          )
+        },
+        err => {
+          if (err) {
+            return callback(err)
+          }
+          console.log('>> done')
+          callback()
+        }
+      )
+    }
+  )
+}
+
+const erasePrefix = (db, callback) => {
+  db.projects.update({$unset: 'tokens.readAndWritePrefix'}, callback)
+}
+
+
+// Migrations
+
+exports.migrate = (client, done) => {
+  console.log(`>> Adding index to projects: ${JSON.stringify(indexKeys)}, with options: ${JSON.stringify(indexOpts)}`)
+  addReadAndWritePrefixIndex(db, (err) => {
+    if(err) {
+      console.log(">> Error while adding index")
+      return done(err)
+    }
+    console.log(">> Extracting tokens.readAndWritePrefix field for existing projects")
+    extractPrefix(db, (err) => {
+      if(err) {
+        console.log(">> Error while extracting prefix data")
+        return done(err)
+      }
+      done()
+    })
+  })
+}
+
+exports.rollback = (client, done) => {
+  console.log(`>> Dropping index on projects: ${JSON.stringify(indexKeys)}`)
+  removeReadAndWritePrefixIndex(db, (err) => {
+    if(err) {
+      console.log(">> Error while dropping index")
+      return done(err)
+    }
+    console.log(">> Erasing tokens.readAndWritePrefix field for existing projects")
+    erasePrefix(db, (err) => {
+      if(err) {
+        console.log(">> Error while erasing prefix data")
+        return done(err)
+      }
+      done()
+    })
+  })
+}