public override void Serialize( BsonWriter bsonWriter, Type nominalType, object value, IBsonSerializationOptions options) { if (value == null) { bsonWriter.WriteNull(); } else { var rawBsonDocument = (RawBsonDocument)value; var slice = rawBsonDocument.Slice; using (var clonedSlice = slice.GetSlice(0, slice.Length)) { bsonWriter.WriteRawBsonDocument(clonedSlice); } } } }