Index: lams_central/src/java/org/lamsfoundation/lams/web/qb/EditQbQuestionController.java
===================================================================
diff -u -r21555f88fd0c63a4a9eb3ae288a2e1d48452aa4b -r9012873415698350686bf05ac1ddb1ee5b8fe154
--- lams_central/src/java/org/lamsfoundation/lams/web/qb/EditQbQuestionController.java	(.../EditQbQuestionController.java)	(revision 21555f88fd0c63a4a9eb3ae288a2e1d48452aa4b)
+++ lams_central/src/java/org/lamsfoundation/lams/web/qb/EditQbQuestionController.java	(.../EditQbQuestionController.java)	(revision 9012873415698350686bf05ac1ddb1ee5b8fe154)
@@ -109,7 +109,8 @@
      */
     @RequestMapping("/editQuestion")
     public String editQuestion(@ModelAttribute("assessmentQuestionForm") QbQuestionForm form,
-	    HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException, IllegalAccessException, InvocationTargetException {
+	    HttpServletRequest request, HttpServletResponse response)
+	    throws ServletException, IOException, IllegalAccessException, InvocationTargetException {
 	Long qbQuestionUid = WebUtil.readLongParam(request, "qbQuestionUid");
 	QbQuestion qbQuestion = qbService.getQuestionByUid(qbQuestionUid);
 	if (qbQuestion == null) {
@@ -144,8 +145,9 @@
 
 	Integer questionType = qbQuestion.getType();
 	if ((questionType == QbQuestion.TYPE_MULTIPLE_CHOICE) || (questionType == QbQuestion.TYPE_ORDERING)
-		|| (questionType == QbQuestion.TYPE_MATCHING_PAIRS) || (questionType == QbQuestion.TYPE_VERY_SHORT_ANSWERS)
-		|| (questionType == QbQuestion.TYPE_NUMERICAL) || (questionType == QbQuestion.TYPE_MARK_HEDGING)) {
+		|| (questionType == QbQuestion.TYPE_MATCHING_PAIRS)
+		|| (questionType == QbQuestion.TYPE_VERY_SHORT_ANSWERS) || (questionType == QbQuestion.TYPE_NUMERICAL)
+		|| (questionType == QbQuestion.TYPE_MARK_HEDGING)) {
 	    List<QbOption> optionList = qbQuestion.getQbOptions();
 	    request.setAttribute(QbConstants.ATTR_OPTION_LIST, optionList);
 	}
@@ -208,21 +210,23 @@
 	}
 	userManagementService.save(qbQuestion);
 
-	final boolean IS_REQUEST_CAME_FROM_ASSESSMENT_TOOL = StringUtils.isNotBlank(form.getSessionMapID());
+	final boolean isRequestCameFromTool = StringUtils.isNotBlank(form.getSessionMapID());
 
 	//take care about question's collections. add to collection first
 	Long oldCollectionUid = form.getOldCollectionUid();
 	Long newCollectionUid = form.getNewCollectionUid();
-	if (isAddingQuestion || (IS_REQUEST_CAME_FROM_ASSESSMENT_TOOL && !newCollectionUid.equals(oldCollectionUid))) {
+	if (isAddingQuestion
+		|| (isRequestCameFromTool && oldCollectionUid != null && !newCollectionUid.equals(oldCollectionUid))) {
 	    qbService.addQuestionToCollection(newCollectionUid, qbQuestion.getQuestionId(), false);
 	}
 
-	//remove from the old collection, if needed
-	if (!isAddingQuestion && IS_REQUEST_CAME_FROM_ASSESSMENT_TOOL && !newCollectionUid.equals(oldCollectionUid)) {
+	//remove from the old collection, if needed and the question is in users' collections
+	if (!isAddingQuestion && isRequestCameFromTool && oldCollectionUid != null
+		&& !newCollectionUid.equals(oldCollectionUid)) {
 	    qbService.removeQuestionFromCollectionByQuestionId(oldCollectionUid, qbQuestion.getQuestionId(), false);
 	}
 
-	if (IS_REQUEST_CAME_FROM_ASSESSMENT_TOOL) {
+	if (isRequestCameFromTool) {
 	    //forward to Assessment controller
 	    String params = "?qbQuestionUid=" + qbQuestion.getUid();
 	    params += "&questionModificationStatus=" + questionModificationStatus;
@@ -286,35 +290,35 @@
 	    qbQuestion.setFeedbackOnCorrect(form.getFeedbackOnCorrect());
 	    qbQuestion.setFeedbackOnPartiallyCorrect(form.getFeedbackOnPartiallyCorrect());
 	    qbQuestion.setFeedbackOnIncorrect(form.getFeedbackOnIncorrect());
-	    
+
 	} else if ((type == QbQuestion.TYPE_MATCHING_PAIRS)) {
 	    qbQuestion.setPenaltyFactor(Float.parseFloat(form.getPenaltyFactor()));
 	    qbQuestion.setShuffle(form.isShuffle());
-	    
+
 	} else if ((type == QbQuestion.TYPE_VERY_SHORT_ANSWERS)) {
 	    qbQuestion.setPenaltyFactor(Float.parseFloat(form.getPenaltyFactor()));
 	    qbQuestion.setCaseSensitive(form.isCaseSensitive());
 	    qbQuestion.setAutocompleteEnabled(form.isAutocompleteEnabled());
-	    
+
 	} else if ((type == QbQuestion.TYPE_NUMERICAL)) {
 	    qbQuestion.setPenaltyFactor(Float.parseFloat(form.getPenaltyFactor()));
-	    
+
 	} else if ((type == QbQuestion.TYPE_TRUE_FALSE)) {
 	    qbQuestion.setPenaltyFactor(Float.parseFloat(form.getPenaltyFactor()));
 	    qbQuestion.setCorrectAnswer(form.isCorrectAnswer());
 	    qbQuestion.setFeedbackOnCorrect(form.getFeedbackOnCorrect());
 	    qbQuestion.setFeedbackOnIncorrect(form.getFeedbackOnIncorrect());
-	    
+
 	} else if ((type == QbQuestion.TYPE_ESSAY)) {
 	    qbQuestion.setAllowRichEditor(form.isAllowRichEditor());
 	    qbQuestion.setMaxWordsLimit(form.getMaxWordsLimit());
 	    qbQuestion.setMinWordsLimit(form.getMinWordsLimit());
-	    
+
 	} else if (type == QbQuestion.TYPE_ORDERING) {
 	    qbQuestion.setPenaltyFactor(Float.parseFloat(form.getPenaltyFactor()));
 	    qbQuestion.setFeedbackOnCorrect(form.getFeedbackOnCorrect());
 	    qbQuestion.setFeedbackOnIncorrect(form.getFeedbackOnIncorrect());
-	    
+
 	} else if (type == QbQuestion.TYPE_MARK_HEDGING) {
 	    qbQuestion.setShuffle(form.isShuffle());
 	    qbQuestion.setFeedbackOnCorrect(form.getFeedbackOnCorrect());
@@ -432,7 +436,8 @@
 	    }
 	    option.setDisplayOrder(NumberUtils.toInt(displayOrder));
 
-	    if ((questionType == QbQuestion.TYPE_MULTIPLE_CHOICE) || (questionType == QbQuestion.TYPE_VERY_SHORT_ANSWERS)) {
+	    if ((questionType == QbQuestion.TYPE_MULTIPLE_CHOICE)
+		    || (questionType == QbQuestion.TYPE_VERY_SHORT_ANSWERS)) {
 		String name = paramMap.get(QbConstants.ATTR_OPTION_NAME_PREFIX + i);
 		if ((name == null) && isForSaving) {
 		    continue;
@@ -500,7 +505,7 @@
 
 	    optionList.add(option);
 	}
-	
+
 //	//in case of VSA make sure it has 2 option groups, one of which having 0 maxMark
 //	if (questionType == QbQuestion.TYPE_VERY_SHORT_ANSWERS && optionList.size() == 1) {
 //	    QbOption option = new QbOption();
@@ -510,7 +515,7 @@
 //	    option.setFeedback("");
 //	    optionList.add(option);
 //	}
-	
+
 	return optionList;
     }
 
Index: lams_central/src/java/org/lamsfoundation/lams/web/qb/QbStatsController.java
===================================================================
diff -u -r21555f88fd0c63a4a9eb3ae288a2e1d48452aa4b -r9012873415698350686bf05ac1ddb1ee5b8fe154
--- lams_central/src/java/org/lamsfoundation/lams/web/qb/QbStatsController.java	(.../QbStatsController.java)	(revision 21555f88fd0c63a4a9eb3ae288a2e1d48452aa4b)
+++ lams_central/src/java/org/lamsfoundation/lams/web/qb/QbStatsController.java	(.../QbStatsController.java)	(revision 9012873415698350686bf05ac1ddb1ee5b8fe154)
@@ -73,7 +73,8 @@
 
 	Integer userId = getUserId();
 	int qbQuestionId = stats.getQuestion().getQuestionId();
-	boolean managementAllowed = qbService.isQuestionInUserCollection(qbQuestionId, userId);
+	boolean managementAllowed = qbService.isQuestionInUserCollection(qbQuestionId, userId)
+		|| qbService.isQuestionInPublicCollection(qbQuestionId);
 	model.addAttribute("managementAllowed", managementAllowed);
 
 	Collection<QbCollection> existingCollections = qbService.getQuestionCollectionsByUid(qbQuestionUid);
Index: lams_central/web/qb/authoring/addQuestionFooter.jsp
===================================================================
diff -u -r9ebb0762842cde9a358626a248132bc7ca650f3c -r9012873415698350686bf05ac1ddb1ee5b8fe154
--- lams_central/web/qb/authoring/addQuestionFooter.jsp	(.../addQuestionFooter.jsp)	(revision 9ebb0762842cde9a358626a248132bc7ca650f3c)
+++ lams_central/web/qb/authoring/addQuestionFooter.jsp	(.../addQuestionFooter.jsp)	(revision 9012873415698350686bf05ac1ddb1ee5b8fe154)
@@ -3,7 +3,8 @@
 <footer class="footer fixed-bottom">
 	<div class="panel-heading ">
        	<div class="col-xs-12x col-md-6x form-groupx rowx form-inlinex btn-group-md voffset5">
-       		<span <c:if test="${empty assessmentQuestionForm.sessionMapID}">style="visibility: hidden;"</c:if>>
+       		<%-- Hide if we edit it on QB collections page or if we edit in a tool but the question is not in users' collections  --%>
+       		<span <c:if test="${empty assessmentQuestionForm.sessionMapID or empty assessmentQuestionForm.userCollections}">style="visibility: hidden;"</c:if>>
 	       		Collection
 	        		
 				<select class="btn btn-md btn-default" id="collection-uid-select">
Index: lams_common/src/java/org/lamsfoundation/lams/qb/QbUtils.java
===================================================================
diff -u -r78b1835bd2936b2de7d98c7eff33621fa9f5e656 -r9012873415698350686bf05ac1ddb1ee5b8fe154
--- lams_common/src/java/org/lamsfoundation/lams/qb/QbUtils.java	(.../QbUtils.java)	(revision 78b1835bd2936b2de7d98c7eff33621fa9f5e656)
+++ lams_common/src/java/org/lamsfoundation/lams/qb/QbUtils.java	(.../QbUtils.java)	(revision 9012873415698350686bf05ac1ddb1ee5b8fe154)
@@ -9,6 +9,7 @@
 import org.apache.commons.lang.StringUtils;
 import org.lamsfoundation.lams.qb.form.QbQuestionForm;
 import org.lamsfoundation.lams.qb.model.QbCollection;
+import org.lamsfoundation.lams.qb.model.QbQuestion;
 import org.lamsfoundation.lams.qb.service.IQbService;
 import org.lamsfoundation.lams.usermanagement.dto.UserDTO;
 import org.lamsfoundation.lams.util.WebUtil;
@@ -32,20 +33,30 @@
 	    : string.trim();
 
     public static void fillFormWithUserCollections(IQbService qbService, QbQuestionForm form, Long qbQuestionUid) {
-	//prepare data for displaying collections
+	final boolean isRequestCameFromTool = StringUtils.isNotBlank(form.getSessionMapID());
 	Integer userId = QbUtils.getUserId();
+	if (isRequestCameFromTool && qbQuestionUid != null) {
+	    QbQuestion qbQuestion = qbService.getQuestionByUid(qbQuestionUid);
+	    boolean isQuestionInUserCollection = qbService.isQuestionInUserCollection(qbQuestion.getQuestionId(),
+		    userId);
+	    if (!isQuestionInUserCollection) {
+		// in a tool the user is editing a question which is not in one of his collections
+		// do not let him change the collection, i.e. steal the question
+		return;
+	    }
+	}
+
+	//prepare data for displaying collections
 	Collection<QbCollection> userCollections = qbService.getUserCollections(userId);
 	form.setUserCollections(userCollections);
 
 	//in case request came not from the tool, collectioUid is already supplied as parameter from collections.jsp
-	final boolean isRequestCameFromTool = StringUtils.isNotBlank(form.getSessionMapID());
 	if (!isRequestCameFromTool) {
 	    return;
 	}
 
 	Collection<QbCollection> questionCollections = qbQuestionUid == null ? new LinkedList<>()
 		: qbService.getQuestionCollectionsByUid(qbQuestionUid);
-
 	Long collectionUid = null;
 	if (questionCollections.isEmpty()) {
 	    //set private collection as default, if question is new or doesn't have associated collection
Index: lams_common/src/java/org/lamsfoundation/lams/qb/dao/IQbDAO.java
===================================================================
diff -u -re00ee97b803f195e523abcd3f765513a58a03d32 -r9012873415698350686bf05ac1ddb1ee5b8fe154
--- lams_common/src/java/org/lamsfoundation/lams/qb/dao/IQbDAO.java	(.../IQbDAO.java)	(revision e00ee97b803f195e523abcd3f765513a58a03d32)
+++ lams_common/src/java/org/lamsfoundation/lams/qb/dao/IQbDAO.java	(.../IQbDAO.java)	(revision 9012873415698350686bf05ac1ddb1ee5b8fe154)
@@ -47,9 +47,9 @@
 
     Map<String, Long> getBurningQuestions(long qbQuestionUid);
 
-    List<QbQuestion> getPagedQuestions(String questionTypes, String collectionUids, int page, int size, String sortBy, String sortOrder,
-	    String searchString);
-    
+    List<QbQuestion> getPagedQuestions(String questionTypes, String collectionUids, int page, int size, String sortBy,
+	    String sortOrder, String searchString);
+
     List<BigInteger> getAllQuestionUids(String collectionUids, String sortBy, String sortOrder, String searchString);
 
     int getCountQuestions(String questionTypes, String collectionUids, String searchString);
@@ -72,6 +72,8 @@
     Set<Integer> getCollectionQuestionIdsExcluded(long collectionUid, Collection<Integer> qbQuestionIds);
 
     boolean isQuestionInUserCollection(int userId, int qbQuestionId);
-    
+
+    boolean isQuestionInPublicCollection(int qbQuestionId);
+
     int mergeQuestions(long sourceQbQUestionUid, long targetQbQuestionUid);
 }
\ No newline at end of file
Index: lams_common/src/java/org/lamsfoundation/lams/qb/dao/hibernate/QbDAO.java
===================================================================
diff -u -rf0002897ed884a8bec78ba8ac9623223e168f2f3 -r9012873415698350686bf05ac1ddb1ee5b8fe154
--- lams_common/src/java/org/lamsfoundation/lams/qb/dao/hibernate/QbDAO.java	(.../QbDAO.java)	(revision f0002897ed884a8bec78ba8ac9623223e168f2f3)
+++ lams_common/src/java/org/lamsfoundation/lams/qb/dao/hibernate/QbDAO.java	(.../QbDAO.java)	(revision 9012873415698350686bf05ac1ddb1ee5b8fe154)
@@ -82,7 +82,7 @@
 
     private static final String ADD_COLLECTION_QUESTION = "INSERT INTO lams_qb_collection_question VALUES (:collectionUid, :qbQuestionId)";
 
-    private static final String EXISTS_COLLECTION_QUESTION = "SELECT 1 FROM lams_qb_collection_question WHERE collection_uid = :collectionUid "
+    private static final String IS_QUESTION_IN_COLLECTION = "SELECT 1 FROM lams_qb_collection_question WHERE collection_uid = :collectionUid "
 	    + "AND qb_question_id = :qbQuestionId";
 
     private static final String REMOVE_COLLECTION_QUESTION = "DELETE FROM lams_qb_collection_question WHERE collection_uid = :collectionUid "
@@ -96,8 +96,12 @@
 
     private static final String IS_QUESTION_IN_USER_COLLECTION = "SELECT DISTINCT 1 FROM lams_qb_collection_question AS cq "
 	    + "JOIN lams_qb_collection AS c ON cq.collection_uid = c.uid AND "
-	    + "(c.user_id = :userId OR c.user_id IS NULL) AND cq.qb_question_id = :qbQuestionId";
+	    + "c.user_id = :userId AND cq.qb_question_id = :qbQuestionId";
 
+    private static final String IS_QUESTION_IN_PUBLIC_COLLECTION = "SELECT DISTINCT 1 FROM lams_qb_collection_question AS cq "
+	    + "JOIN lams_qb_collection AS c ON cq.collection_uid = c.uid AND "
+	    + "c.user_id IS NULL AND cq.qb_question_id = :qbQuestionId";
+
     private static final String GENERATE_QUESTION_ID = "INSERT INTO lams_sequence_generator(lams_qb_question_question_id) VALUES (:qbQuestionId)";
 
     private static final String MERGE_TOOL_QUESTIONS = "UPDATE QbToolQuestion SET qbQuestion.uid = :targetQbQuestionUid WHERE qbQuestion.uid = :sourceQbQuestionUid";
@@ -381,7 +385,7 @@
 
     @Override
     public void addCollectionQuestion(long collectionUid, int qbQuestionId) {
-	if (!questionInCollectionExists(collectionUid, qbQuestionId)) {
+	if (!isQuestionInCollection(collectionUid, qbQuestionId)) {
 	    getSession().createNativeQuery(ADD_COLLECTION_QUESTION).setParameter("collectionUid", collectionUid)
 		    .setParameter("qbQuestionId", qbQuestionId).executeUpdate();
 	}
@@ -412,8 +416,14 @@
 		.setParameter("qbQuestionId", qbQuestionId).uniqueResult() != null;
     }
 
-    private boolean questionInCollectionExists(long collectionUid, int qbQuestionId) {
-	return !getSession().createNativeQuery(EXISTS_COLLECTION_QUESTION).setParameter("collectionUid", collectionUid)
+    @Override
+    public boolean isQuestionInPublicCollection(int qbQuestionId) {
+	return getSession().createNativeQuery(IS_QUESTION_IN_PUBLIC_COLLECTION)
+		.setParameter("qbQuestionId", qbQuestionId).uniqueResult() != null;
+    }
+
+    private boolean isQuestionInCollection(long collectionUid, int qbQuestionId) {
+	return !getSession().createNativeQuery(IS_QUESTION_IN_COLLECTION).setParameter("collectionUid", collectionUid)
 		.setParameter("qbQuestionId", qbQuestionId).getResultList().isEmpty();
     }
 
Index: lams_common/src/java/org/lamsfoundation/lams/qb/service/IQbService.java
===================================================================
diff -u -re00ee97b803f195e523abcd3f765513a58a03d32 -r9012873415698350686bf05ac1ddb1ee5b8fe154
--- lams_common/src/java/org/lamsfoundation/lams/qb/service/IQbService.java	(.../IQbService.java)	(revision e00ee97b803f195e523abcd3f765513a58a03d32)
+++ lams_common/src/java/org/lamsfoundation/lams/qb/service/IQbService.java	(.../IQbService.java)	(revision 9012873415698350686bf05ac1ddb1ee5b8fe154)
@@ -137,6 +137,8 @@
 
     boolean isQuestionInUserCollection(int qbQuestionId, int userId);
 
+    boolean isQuestionInPublicCollection(int qbQuestionId);
+
     void insertQuestion(QbQuestion qbQuestion);
 
     void prepareQuestionForExport(QbQuestion qbQuestion);
Index: lams_common/src/java/org/lamsfoundation/lams/qb/service/QbService.java
===================================================================
diff -u -r0483acb3c9e3b07f42d9511bbfea3708029438e8 -r9012873415698350686bf05ac1ddb1ee5b8fe154
--- lams_common/src/java/org/lamsfoundation/lams/qb/service/QbService.java	(.../QbService.java)	(revision 0483acb3c9e3b07f42d9511bbfea3708029438e8)
+++ lams_common/src/java/org/lamsfoundation/lams/qb/service/QbService.java	(.../QbService.java)	(revision 9012873415698350686bf05ac1ddb1ee5b8fe154)
@@ -583,6 +583,11 @@
 	return qbDAO.isQuestionInUserCollection(userId, qbQuestionId);
     }
 
+    @Override
+    public boolean isQuestionInPublicCollection(int qbQuestionId) {
+	return qbDAO.isQuestionInPublicCollection(qbQuestionId);
+    }
+
     /**
      * Cascades in QbToolQuestion, QbQuestion and QbOptions do not seem to work on insert.
      * New QbQuestions need to be saved step by step.