> ## Documentation Index > Fetch the complete documentation index at: https://documentation.claruswms.com/llms.txt > Use this file to discover all available pages before exploring further. # SBD and BBD Date Validation > How the HHD system validates Sell By and Best Before dates to prevent out-of-date stock from being received into the warehouse. ## Preventing out-of-date stock The Handheld Device (HHD) system automatically validates any entered **Sell By Date (SBD)** or **Best Before Date (BBD)** against the current system date and time. This prevents expired stock from being accidentally received or entered into the system. ## How it works Consider a standard "blind receipt" workflow: When prompted, you enter a Sell By or Best Before date on the HHD. If today's date is **11/03/2026** and you enter an expired date such as **10/03/2025**, the system triggers an immediate alert. HHD screen showing an expired date entry triggering an alert An error message is displayed, blocking you from proceeding with a date in the past. HHD error message blocking progress due to an expired date Once you correct the date to a valid future date (e.g., **12/03/2026**), the system validates the entry and allows you to continue. HHD screen accepting a corrected valid future date This validation works identically for both **Sell By** and **Best Before** date fields. This safeguard helps improve inventory accuracy and reduce waste by catching date entry errors at the point of receipt.