A federal judge has ruled that a lawsuit against McCormick & Co. over its ground pepper tins can go forward, denying the company’s motion to dismiss.

Lawsuit over size of pepper tins to continue 

Read more: Toilet paper isn’t the only thing that’s shrinking

Watkins Inc., a smaller spice maker, sued McCormick last year after discovering the company had removed 25% of its product but still used the same old tins.

The picture below, which was released by Watkins, will help you understand their case.

The McCormick tins appear to be the same size, but the tin on the left contains 8 ounces of ground black pepper and the one in the middle has 6 ounces. The smaller Watkins tin also contains 6 ounces of pepper.

So Watkins is arguing that McCormick was deceiving customers by reducing the amount of pepper in its non-transparent containers while not reducing the size of the tins.

Watkins claims the move hurt sales of its spices, which are often displayed right next to McCormick’s products.

As the Minneapolis Star Tribune has reported, McCormick says there was no false advertising because the correct product weight was always listed on the front label.

McCormick also faces a class-action lawsuit from consumers over the matter.

Bottom line: While this case makes its way through the federal court system, it’s a good reminder for shoppers to pay attention to a product’s weight, not simply the price alone.

Read more: 8 things that cost more at the grocery store (and where to get them cheaper)

Clark’s key tips for avoiding long supermarket lines