Is the omission of the verb "To be" in informative sentence [duplicate]

I have the following sentence:

File (is) larger than allowed.

Is the verb "to be" required here?

Is it correct English to use "File larger than allowed."?


Although not exactly a sentence, we often get this kind of telegraphic answer from computers. Look at these examples:

  • "suitcase heavier than allowed" - from automatic scale at the airport
  • "file larger than allowed" - from a data traveler
  • "daily limit exceeded" - from an automatic teller machine