diff --git a/backend/main.go b/backend/main.go
index 76caea84..44e44ee2 100644
--- a/backend/main.go
+++ b/backend/main.go
@@ -47,6 +47,7 @@ func main() {
 	flag.StringVar(&TeamsDir, "teams", "../TEAMS", "Base directory where save teams JSON files")
 	flag.StringVar(&fic.FilesDir, "files", "/files", "Request path prefix to reach files")
 	var skipFullGeneration = flag.Bool("skipFullGeneration", false, "Skip initial full generation (safe to skip after start)")
+	flag.BoolVar(&fic.PartialValidation, "partialValidation", false, "Validates flags which are corrects, don't be binary")
 	flag.BoolVar(&fic.UnlockedChallenges, "unlockedChallenges", false, "Make all challenges accessible without having to validate previous level")
 	flag.Parse()
 
diff --git a/frontend/static/js/app.js b/frontend/static/js/app.js
index 21f8aee3..bdee2f12 100644
--- a/frontend/static/js/app.js
+++ b/frontend/static/js/app.js
@@ -197,7 +197,7 @@ angular.module("FICApp")
 
     })
     .controller("SubmissionController", function($scope, $http, $rootScope, $timeout) {
-	$scope.flags = []
+	$scope.flags = [];
 	$rootScope.sberr = "";
 
 	var waitMy = function() {
@@ -205,12 +205,16 @@ angular.module("FICApp")
 		$timeout.cancel($scope.cbs);
 		$scope.cbs = $timeout(waitMy, 420);
 	    } else {
+		$scope.flags = [];
 		angular.forEach($scope.my.exercices[$rootScope.current_exercice].keys, function(key,kid) {
-		    this.push({
+		    var o = {
 			id: kid,
 			name: key,
 			value: ""
-		    });
+		    };
+		    if ($scope.my.exercices[$rootScope.current_exercice].solved_matrix != null)
+			o.found = $scope.my.exercices[$rootScope.current_exercice].solved_matrix[kid];
+		    this.push(o);
 		}, $scope.flags);
 	    }
 	}
@@ -219,23 +223,10 @@ angular.module("FICApp")
 	$scope.ssubmit = function() {
 	    var flgs = {}
 
-	    var filled = true;
 	    angular.forEach($scope.flags, function(flag,kid) {
 		flgs[flag.name] = flag.value;
-		filled = filled && flag.value.length > 0;
 	    });
 
-	    if (!filled) {
-		$rootScope.messageClass = {"text-danger": true};
-		$rootScope.sberr = "Tous les champs sont obligatoires.";
-		$timeout(function() {
-		    if ($rootScope.sberr == "Tous les champs sont obligatoires.") {
-			$rootScope.sberr = "";
-		    }
-		}, 2345);
-		return;
-	    }
-
 	    $http({
 		url: "/submit/" + $rootScope.current_exercice,
 		method: "POST",
diff --git a/frontend/static/views/theme.html b/frontend/static/views/theme.html
index 8dc8074b..e2bbec27 100644
--- a/frontend/static/views/theme.html
+++ b/frontend/static/views/theme.html
@@ -52,9 +52,10 @@
 	    </ul>
 	    <div class="panel-body" ng-show="!my.exercices[current_exercice].submitted || sberr">
 	      <form ng-controller="SubmissionController" ng-submit="ssubmit()">
-		<div class="form-group" ng-repeat="key in flags">
+		<div class="form-group" ng-repeat="key in flags" ng-class="{'has-success': key.found, 'has-feedback': key.found}">
 		  <label for="sol_{{ key.id }}">{{ key.name }} :</label>
-		  <input type="text" class="form-control" id="sol_{{ key.id }}" name="sol_{{ index }}" ng-model="key.value">
+		  <input type="text" class="form-control" id="sol_{{ key.id }}" name="sol_{{ index }}" ng-model="key.value" ng-disabled="key.found">
+		  <span class="glyphicon glyphicon-ok form-control-feedback" aria-hidden="true" ng-show="key.found"></span>
 		</div>
 		<div class="form-group text-right">
 		  <button type="submit" class="btn btn-danger" id="sbmt">Soumettre</button>
diff --git a/libfic/db.go b/libfic/db.go
index b3bb4e31..05134b03 100644
--- a/libfic/db.go
+++ b/libfic/db.go
@@ -107,6 +107,17 @@ CREATE TABLE IF NOT EXISTS exercice_keys(
   value BINARY(64) NOT NULL,
   FOREIGN KEY(id_exercice) REFERENCES exercices(id_exercice)
 );
+`); err != nil {
+		return err
+	}
+	if _, err := db.Exec(`
+CREATE TABLE IF NOT EXISTS key_found(
+  id_key INTEGER NOT NULL,
+  id_team INTEGER NOT NULL,
+  time TIMESTAMP NOT NULL,
+  FOREIGN KEY(id_key) REFERENCES exercice_keys(id_key),
+  FOREIGN KEY(id_team) REFERENCES teams(id_team)
+);
 `); err != nil {
 		return err
 	}
diff --git a/libfic/exercice.go b/libfic/exercice.go
index 6af662d4..4f3c1211 100644
--- a/libfic/exercice.go
+++ b/libfic/exercice.go
@@ -5,6 +5,8 @@ import (
 	"time"
 )
 
+var PartialValidation bool
+
 type Exercice struct {
 	Id        int64  `json:"id"`
 	Title     string `json:"title"`
@@ -201,13 +203,14 @@ func (e Exercice) CheckResponse(resps map[string]string, t Team) (bool, error) {
 
 		valid := true
 		for _, key := range keys {
-			if _, ok := resps[key.Type]; !ok {
+			if res, ok := resps[key.Type]; !ok {
 				valid = false
-				break
-			}
-			if !key.Check(resps[key.Type]) {
-				valid = false
-				break
+			} else if !key.Check(res) {
+				if !PartialValidation || t.HasPartiallySolved(key) == nil {
+					valid = false
+				}
+			} else {
+				key.FoundBy(t)
 			}
 		}
 
diff --git a/libfic/key.go b/libfic/key.go
index a1a32d39..853f7166 100644
--- a/libfic/key.go
+++ b/libfic/key.go
@@ -2,6 +2,7 @@ package fic
 
 import (
 	"crypto/sha512"
+	"time"
 )
 
 type Key struct {
@@ -88,3 +89,7 @@ func (k Key) Check(val string) bool {
 
 	return true
 }
+
+func (k Key) FoundBy(t Team) {
+	DBExec("INSERT INTO key_found (id_key, id_team, time) VALUES (?, ?, ?)", k.Id, t.Id, time.Now())
+}
diff --git a/libfic/team.go b/libfic/team.go
index 920ab6fd..27fbb40a 100644
--- a/libfic/team.go
+++ b/libfic/team.go
@@ -244,6 +244,12 @@ func IsSolved(e Exercice) (int, time.Time) {
 	}
 }
 
+func (t Team) HasPartiallySolved(k Key) (*time.Time) {
+	var tm *time.Time
+	DBQueryRow("SELECT MIN(time) FROM key_found WHERE id_team = ? AND id_key = ?", t.Id, k.Id).Scan(&tm)
+	return tm
+}
+
 type statLine struct {
 	Tip    string `json:"tip"`
 	Total  int    `json:"total"`
diff --git a/libfic/team_my.go b/libfic/team_my.go
index 3626fcf1..06b218e7 100644
--- a/libfic/team_my.go
+++ b/libfic/team_my.go
@@ -28,6 +28,7 @@ type myTeamExercice struct {
 	Files        []myTeamFile `json:"files"`
 	Keys         []string     `json:"keys"`
 	Solved       bool         `json:"solved"`
+	SolvedMat    []bool       `json:"solved_matrix"`
 	SolvedTime   time.Time    `json:"solved_time"`
 	SolvedNumber int64        `json:"solved_number"`
 	VideoURI     string       `json:"video_uri"`
@@ -116,6 +117,9 @@ func MyJSONTeam(t *Team, started bool) (interface{}, error) {
 							exercice.Keys = append(exercice.Keys, fmt.Sprintf("%x", k.Value)+k.Type)
 						} else {
 							exercice.Keys = append(exercice.Keys, k.Type)
+							if PartialValidation {
+								exercice.SolvedMat = append(exercice.SolvedMat, t.HasPartiallySolved(k) != nil)
+							}
 						}
 					}
 				}