diff --git a/app/models/grade.rb b/app/models/grade.rb
index b7c535f..40b2171 100644
--- a/app/models/grade.rb
+++ b/app/models/grade.rb
@@ -5,12 +5,4 @@ class Grade < ApplicationRecord
   validates_numericality_of :grade , :less_than_or_equal_to=>100, :greater_than_or_equal_to=>0, :allow_nil => true
   validates :lecture, presence: true
   validates :student, presence: true
-  validate :submission_size_validation
-
-  def submission_size_validation
-    if submission.attached?
-      errors[:grade] << "attachment must be less than 500kB" if submission.blob.byte_size > 500.kilobytes
-      errors[:grade] << "attachment must be a pdf" if submission.filename.extension != "pdf"
-    end
-  end 
 end