A SME owner recently asked me if switching from paper timesheets to a time tracking app was "legal" or if they would be sanctioned for not using a punch clock. The confusion is common and it is worth clearing it up from the start: Argentine regulations do not require the use of a specific format for record-keeping. It does not say "physical clock," it does not say "paper timesheet," it does not say "biometric." What the Ministry of Human Capital and a labor judge will look at is something else: whether that record is reliable, unalterable, and serves as evidence. Here I explain what makes a digital clock-in system valid and what causes it to fail during an inspection or in a lawsuit.