Costco is cracking down on non-members using membership cards that don’t belong to them.

The company has started scanning membership cards at various locations. Instead of just flashing your card to an employee as you enter warehouse stores, the retailer asked members to scan the back of their cards or their digital membership QR codes, reports KTLA.

The change started earlier this year and now appears to be rolling out nationally. In California, the new membership scanners have already been spotted at Costco locations in Huntington Beach and Inglewood.

Costco confirmed the changes in a statement on its website.

“Over the coming months, membership scanning devices will be used at the entrance door of your local warehouse. Once deployed, prior to entering, all members must scan their physical or digital membership card by placing the barcode or QR Code against the scanner. Guests must also be accompanied by a valid member for entry,” the warehouse chain said.

“If your membership is inactive, expired, or you would like to sign up for a new membership, the attendant will ask that you stop by the membership counter prior to entering the warehouse to shop. Additionally, if your membership card does not have a photo, please be prepared to show your valid photo ID.”

Since Costco expanded its self-checkout, the store has noticed that non-members have been sneaking in with membership cards that don’t belong to them, reports CBS News.

“We don’t feel it’s right that non-members receive the same benefits and pricing as our members,” Costco said about the change, according to CNN.