It can be tough when you don’t get enough coffee in the morning — you’re tired and cranky all day, your coworkers hide from your scorching gaze, etc. — and you have no one to blame but yourself for not getting more caffeine. Some Starbucks customers are blaming their lack of coffee on the company, claiming in a class action lawsuit that the chain consistently underfills its lattes.

Customers claim in the putative class action filed in the U.S. District Court for the Northern District of California that although Starbucks advertises 12-ounce, 16-ounce, and 20-ounce serving sizes, the coffee company intentionally underfills its lattes by 25%, Top Class Actions reports.

Starbucks baristas follow a standardized company formula for making lattes, the lawsuit claims. Those instructions have baristas filling a pitcher with steamed milk up to a “fill to line,” then pouring shots of espresso into a serving cup, adding the steamed milk, and topping the latte with milk foam, to leave 1/4 inch of free space at the top.

But two latte drinkers who frequent Starbucks say in their suit that the “fill to” lines don’t measure up to the 12, 16, and 20 fluid ounce cup sizes customers buy.

“Tall Lattes are not 12 fluid ounces, Grande Lattes are not 16 fluid ounces, and Venti Lattes are not 20 fluid ounces,” the class action states. “Starbucks cheats purchasers by providing less fluid ounces in their Lattes than represented.”

This is all a conscious decision by the coffee chain, the plaintiffs allege, made in 2009 as an effort to save on the cost of milk, which is one of its most expensive ingredients.

The “fill to” line means each and every latte is short by several ounces, the lawsuit claims.

“Moreover, Starbucks refuses to fill any hot beverage up to the brim of the cup. Thus, under no circumstances will Starbucks ever serve a Grande Latte that actually meets the fluid ounces represented on the menu,” the Starbucks lawsuit states.

Underfilling the lattes amounts to breach of express and implied warranties as well as liable for unjust enrichment, the customers claim.

If the class action lawsuit is approved, it’ll be open to any class members in the U.S. who have bought a Starbucks latte.

“We are aware of the plaintiffs’ claims, which we fully believe to be without merit,” a Starbucks spokesperson told Consumerist. “We are proud to serve our customers high-quality, handcrafted and customized beverages, and we inform customers of the likelihood of variations.”

Starbucks Class Action Says Lattes Are Intentionally Underfilled [Top Class Actions]

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