diff --git a/lib/api/filters.js b/lib/api/filters.js
index 95e15a1..3f02e09 100644
--- a/lib/api/filters.js
+++ b/lib/api/filters.js
@@ -525,7 +525,7 @@ module.exports = (db, server) => {
                         .empty(''),
                     size: Joi.number().empty('')
                 })
-                .required(),
+                .default({}),
             action: Joi.object()
                 .keys({
                     seen: Joi.boolean()
@@ -560,7 +560,7 @@ module.exports = (db, server) => {
                         )
                         .empty('')
                 })
-                .required()
+                .default({})
         });
 
         const result = Joi.validate(req.params, schema, {
@@ -591,35 +591,27 @@ module.exports = (db, server) => {
             filterData.name = result.value.name;
         }
 
-        let hasQuery = false;
-        let hasAction = false;
-
         ['from', 'to', 'subject'].forEach(key => {
             if (result.value.query[key]) {
                 filterData.query.headers[key] = result.value.query[key].replace(/\s+/g, ' ');
-                hasQuery = true;
             }
         });
 
         if (result.value.query.text) {
             filterData.query.text = result.value.query.text.replace(/\s+/g, ' ');
-            hasQuery = true;
         }
 
         if (typeof result.value.query.ha === 'boolean') {
             filterData.query.ha = result.value.query.ha;
-            hasQuery = true;
         }
 
         if (result.value.query.size) {
             filterData.query.size = result.value.query.size;
-            hasQuery = true;
         }
 
         ['seen', 'flag', 'delete', 'spam'].forEach(key => {
             if (typeof result.value.action[key] === 'boolean') {
                 filterData.action[key] = result.value.action[key];
-                hasAction = true;
             }
         });
 
@@ -657,7 +649,6 @@ module.exports = (db, server) => {
             }
 
             filterData.action.targets = targets;
-            hasAction = true;
         }
 
         let checkFilterMailbox = done => {
@@ -684,27 +675,12 @@ module.exports = (db, server) => {
                         return next();
                     }
                     filterData.action.mailbox = mailboxData._id;
-                    hasAction = true;
                     done();
                 }
             );
         };
 
         checkFilterMailbox(() => {
-            if (!hasQuery) {
-                res.json({
-                    error: 'Empty filter query'
-                });
-                return next();
-            }
-
-            if (!hasAction) {
-                res.json({
-                    error: 'Empty filter action'
-                });
-                return next();
-            }
-
             db.users.collection('users').findOne(
                 {
                     _id: user
@@ -826,62 +802,66 @@ module.exports = (db, server) => {
                 .max(255)
                 .empty(''),
 
-            query: Joi.object().keys({
-                from: Joi.string()
-                    .trim()
-                    .max(255)
-                    .empty(''),
-                to: Joi.string()
-                    .trim()
-                    .max(255)
-                    .empty(''),
-                subject: Joi.string()
-                    .trim()
-                    .max(255)
-                    .empty(''),
-                text: Joi.string()
-                    .trim()
-                    .max(255)
-                    .empty(''),
-                ha: Joi.boolean()
-                    .truthy(['Y', 'true', 'yes', 'on', 1])
-                    .falsy(['N', 'false', 'no', 'off', 0, ''])
-                    .empty(''),
-                size: Joi.number().empty('')
-            }),
-            action: Joi.object().keys({
-                seen: Joi.boolean()
-                    .truthy(['Y', 'true', 'yes', 'on', 1])
-                    .falsy(['N', 'false', 'no', 'off', 0, ''])
-                    .empty(''),
-                flag: Joi.boolean()
-                    .truthy(['Y', 'true', 'yes', 'on', 1])
-                    .falsy(['N', 'false', 'no', 'off', 0, ''])
-                    .empty(''),
-                delete: Joi.boolean()
-                    .truthy(['Y', 'true', 'yes', 'on', 1])
-                    .falsy(['N', 'false', 'no', 'off', 0, ''])
-                    .empty(''),
-                spam: Joi.boolean()
-                    .truthy(['Y', 'true', 'yes', 'on', 1])
-                    .falsy(['N', 'false', 'no', 'off', 0, ''])
-                    .empty(''),
-                mailbox: Joi.string()
-                    .hex()
-                    .lowercase()
-                    .length(24)
-                    .empty(''),
-                targets: Joi.array()
-                    .items(
-                        Joi.string().email(),
-                        Joi.string().uri({
-                            scheme: [/smtps?/, /https?/],
-                            allowRelative: false,
-                            relativeOnly: false
-                        })
-                    )
-                    .empty('')
-            })
+            query: Joi.object()
+                .keys({
+                    from: Joi.string()
+                        .trim()
+                        .max(255)
+                        .empty(''),
+                    to: Joi.string()
+                        .trim()
+                        .max(255)
+                        .empty(''),
+                    subject: Joi.string()
+                        .trim()
+                        .max(255)
+                        .empty(''),
+                    text: Joi.string()
+                        .trim()
+                        .max(255)
+                        .empty(''),
+                    ha: Joi.boolean()
+                        .truthy(['Y', 'true', 'yes', 'on', 1])
+                        .falsy(['N', 'false', 'no', 'off', 0, ''])
+                        .empty(''),
+                    size: Joi.number().empty('')
+                })
+                .default({}),
+            action: Joi.object()
+                .keys({
+                    seen: Joi.boolean()
+                        .truthy(['Y', 'true', 'yes', 'on', 1])
+                        .falsy(['N', 'false', 'no', 'off', 0, ''])
+                        .empty(''),
+                    flag: Joi.boolean()
+                        .truthy(['Y', 'true', 'yes', 'on', 1])
+                        .falsy(['N', 'false', 'no', 'off', 0, ''])
+                        .empty(''),
+                    delete: Joi.boolean()
+                        .truthy(['Y', 'true', 'yes', 'on', 1])
+                        .falsy(['N', 'false', 'no', 'off', 0, ''])
+                        .empty(''),
+                    spam: Joi.boolean()
+                        .truthy(['Y', 'true', 'yes', 'on', 1])
+                        .falsy(['N', 'false', 'no', 'off', 0, ''])
+                        .empty(''),
+                    mailbox: Joi.string()
+                        .hex()
+                        .lowercase()
+                        .length(24)
+                        .empty(''),
+                    targets: Joi.array()
+                        .items(
+                            Joi.string().email(),
+                            Joi.string().uri({
+                                scheme: [/smtps?/, /https?/],
+                                allowRelative: false,
+                                relativeOnly: false
+                            })
+                        )
+                        .empty('')
+                })
+                .default({})
         });
 
         const result = Joi.validate(req.params, schema, {
@@ -910,93 +890,89 @@ module.exports = (db, server) => {
             hasChanges = true;
         }
 
-        if (result.value.query) {
-            ['from', 'to', 'subject'].forEach(key => {
-                if (result.value.query[key]) {
-                    $set['query.headers.' + key] = result.value.query[key].replace(/\s+/g, ' ');
-                    hasChanges = true;
-                } else if (key in req.params.query) {
-                    // delete empty values
-                    $unset['query.headers.' + key] = true;
-                    hasChanges = true;
-                }
-            });
-
-            if (result.value.query.text) {
-                $set['query.text'] = result.value.query.text.replace(/\s+/g, ' ');
+        ['from', 'to', 'subject'].forEach(key => {
+            if (result.value.query[key]) {
+                $set['query.headers.' + key] = result.value.query[key].replace(/\s+/g, ' ');
                 hasChanges = true;
-            } else if ('text' in req.params.query) {
-                $unset['query.text'] = true;
+            } else if (key in req.params.query) {
+                // delete empty values
+                $unset['query.headers.' + key] = true;
                 hasChanges = true;
             }
+        });
 
-            if (typeof result.value.query.ha === 'boolean') {
-                $set['query.ha'] = result.value.query.ha;
-                hasChanges = true;
-            } else if ('ha' in req.params.query) {
-                $unset['query.ha'] = true;
-                hasChanges = true;
-            }
-
-            if (result.value.query.size) {
-                $set['query.size'] = result.value.query.size;
-                hasChanges = true;
-            } else if ('size' in req.params.query) {
-                $unset['query.size'] = true;
-                hasChanges = true;
-            }
+        if (result.value.query.text) {
+            $set['query.text'] = result.value.query.text.replace(/\s+/g, ' ');
+            hasChanges = true;
+        } else if ('text' in req.params.query) {
+            $unset['query.text'] = true;
+            hasChanges = true;
         }
 
-        if (result.value.action) {
-            ['seen', 'flag', 'delete', 'spam'].forEach(key => {
-                if (typeof result.value.action[key] === 'boolean') {
-                    $set['action.' + key] = result.value.action[key];
-                    hasChanges = true;
-                } else if (key in req.params.action) {
-                    $unset['action.' + key] = true;
-                    hasChanges = true;
-                }
-            });
+        if (typeof result.value.query.ha === 'boolean') {
+            $set['query.ha'] = result.value.query.ha;
+            hasChanges = true;
+        } else if ('ha' in req.params.query) {
+            $unset['query.ha'] = true;
+            hasChanges = true;
+        }
 
-            let targets = result.value.action.targets;
+        if (result.value.query.size) {
+            $set['query.size'] = result.value.query.size;
+            hasChanges = true;
+        } else if ('size' in req.params.query) {
+            $unset['query.size'] = true;
+            hasChanges = true;
+        }
 
-            if (targets) {
-                for (let i = 0, len = targets.length; i < len; i++) {
-                    let target = targets[i];
-                    if (!/^smtps?:/i.test(target) && !/^https?:/i.test(target) && target.indexOf('@') >= 0) {
-                        // email
-                        targets[i] = {
-                            id: new ObjectID(),
-                            type: 'mail',
-                            value: target
-                        };
-                    } else if (/^smtps?:/i.test(target)) {
-                        targets[i] = {
-                            id: new ObjectID(),
-                            type: 'relay',
-                            value: target
-                        };
-                    } else if (/^https?:/i.test(target)) {
-                        targets[i] = {
-                            id: new ObjectID(),
-                            type: 'http',
-                            value: target
-                        };
-                    } else {
-                        res.json({
-                            error: 'Unknown target type "' + target + '"',
-                            code: 'InputValidationError'
-                        });
-                        return next();
-                    }
-                }
-
-                $set['action.targets'] = targets;
+        ['seen', 'flag', 'delete', 'spam'].forEach(key => {
+            if (typeof result.value.action[key] === 'boolean') {
+                $set['action.' + key] = result.value.action[key];
                 hasChanges = true;
-            } else if ('targets' in req.params.action) {
-                $unset['action.targets'] = true;
+            } else if (key in req.params.action) {
+                $unset['action.' + key] = true;
                 hasChanges = true;
             }
+        });
+
+        let targets = result.value.action.targets;
+
+        if (targets) {
+            for (let i = 0, len = targets.length; i < len; i++) {
+                let target = targets[i];
+                if (!/^smtps?:/i.test(target) && !/^https?:/i.test(target) && target.indexOf('@') >= 0) {
+                    // email
+                    targets[i] = {
+                        id: new ObjectID(),
+                        type: 'mail',
+                        value: target
+                    };
+                } else if (/^smtps?:/i.test(target)) {
+                    targets[i] = {
+                        id: new ObjectID(),
+                        type: 'relay',
+                        value: target
+                    };
+                } else if (/^https?:/i.test(target)) {
+                    targets[i] = {
+                        id: new ObjectID(),
+                        type: 'http',
+                        value: target
+                    };
+                } else {
+                    res.json({
+                        error: 'Unknown target type "' + target + '"',
+                        code: 'InputValidationError'
+                    });
+                    return next();
+                }
+            }
+
+            $set['action.targets'] = targets;
+            hasChanges = true;
+        } else if ('targets' in req.params.action) {
+            $unset['action.targets'] = true;
+            hasChanges = true;
         }
 
         let checkFilterMailbox = done => {