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diff --git a/src/mongo/s/query/router_stage_aggregation_merge.h b/src/mongo/s/query/router_stage_aggregation_merge.h
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+/**
+ * Copyright (C) 2017 MongoDB Inc.
+ *
+ * This program is free software: you can redistribute it and/or  modify
+ * it under the terms of the GNU Affero General Public License, version 3,
+ * as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU Affero General Public License for more details.
+ *
+ * You should have received a copy of the GNU Affero General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ *
+ * As a special exception, the copyright holders give permission to link the
+ * code of portions of this program with the OpenSSL library under certain
+ * conditions as described in each individual source file and distribute
+ * linked combinations including the program with the OpenSSL library. You
+ * must comply with the GNU Affero General Public License in all respects
+ * for all of the code used other than as permitted herein. If you modify
+ * file(s) with this exception, you may extend this exception to your
+ * version of the file(s), but you are not obligated to do so. If you do not
+ * wish to do so, delete this exception statement from your version. If you
+ * delete this exception statement from all source files in the program,
+ * then also delete it in the license file.
+ */
+
+#pragma once
+
+#include "mongo/s/query/router_exec_stage.h"
+
+#include "mongo/db/pipeline/pipeline.h"
+
+namespace mongo {
+
+/**
+ * Draws results from a Pipeline with a DocumentSourceMergeCursors at its head, which is the
+ * underlying source of the stream of merged documents manipulated by the RouterStage pipeline.
+ */
+class RouterStageAggregationMerge final : public RouterExecStage {
+public:
+    RouterStageAggregationMerge(std::unique_ptr<Pipeline, Pipeline::Deleter> mergePipeline);
+
+    StatusWith<ClusterQueryResult> next() final;
+
+    void kill(OperationContext* opCtx) final;
+
+    bool remotesExhausted() final;
+
+    Status setAwaitDataTimeout(Milliseconds awaitDataTimeout) final;
+
+protected:
+    void doReattachToOperationContext() final;
+
+    void doDetachFromOperationContext() final;
+
+private:
+    std::unique_ptr<Pipeline, Pipeline::Deleter> _mergePipeline;
+};
+
+}  // namespace mongo