Can't Have/Couldn't Have (in english grammar)

• Can't Have/Couldn't Have

• 
• Use can't have or couldn't have to show we are certain something didn't happen in the past, or that it was impossible.

  
  

  subject + can’t/couldn't have + past participle

  -I can’t have spent all my money.

  -I couldn't have spent all my money.

  (The speaker believes it is impossible that she spent all her money.)

• The bank can't have denied my loan application.  I have great credit!	They can't have arrived earlier than us.  We left the house before they did.
  Sam can't have paid his own phone bill.  He is completely broke.	My parents couldn't have made an electronic transfer.  They don't know how to use the bank's app.

 Source : Alison