Have you ever gone to a Starbucks to get your morning pick-me-up to find yourself suspiciously unfulfilled? Well, you're not the only one, and a new lawsuit alleges that the coffee chain has been underfilling its lattes by about 25 percent for years.

The lawsuit was filed in Northern California on behalf of Siera Strumlauf and Benjamin Robles, two locals who often purchase Grande-sized lattes from Starbucks, who accuse the chain of deliberately underfilling its latte cups in order to save money.

Seeking class action status on behalf of buyers of Starbucks caffe lattes and flavored lattes, the lawsuit argues that despite listing at its retail locations that lattes contain 12 fluid ounces for its Tall size, 16 ounces for Grande and 20 ounces for Venti, Starbucks "cheats" purchasers by providing less fluid ounces in its lattes than what's advertised.

This is apparently done through a standardized recipe which was instituted in 2009 in order to save money on milk - one of the more costly ingredients in the recipe.

"The standardized recipe requires Starbucks baristas to fill a pitcher with steamed milk up to an etched 'fill to' line that corresponds to the size of the customer's order, pour shots of espresso into a separate serving cup, pour the steamed milk from the pitcher into the serving cup, then top with one-quarter of an inch of milk foam, leaving a fourth of an inch of free space in the cup," according to the suit.

This results in "beverages that are plainly underfilled" and "moreover, the serving cups used by Starbucks for its lattes are simply too small to accommodate the fluid ounces listed on Starbucks' menu," the lawsuit states.

It turns out that there is quite a bit of merit behind these allegations too. NBC's Jeff Rossen conducted an independent study through the consultation of two labs, which helped to devise a methodology for the procedure. After ordering the same Grande latte at six different Starbucks locations, then measuring them in laboratory-grade beakers after allowing the foam to settle, Rossen did indeed find that each of the lattes had been filled below what was advertised.

However, Starbucks dismissed the findings, saying the method "ignores how lattes are composed and their physical attributes when handed to the customer," and that "the hand-prepared nature of our beverages increases the likelihood of variations in the cup."

That statement mirrored what was said about the initial lawsuit, which was deemed to be "without merit."

"Hand-prepared beverages increase the likelihood of variations, as disclosed in the nutritional section of our website," a Starbucks spokesperson said. "Customers often tell us how they want their beverage prepared (e.g. with room, extra foam), therefore beverage volumes are largely collaborative."

Starbucks does say that customers who are unhappy with their beverage preparation can ask to get a new one made free of charge, but that declaration does little to help all those who may have been shortchanged by Starbucks over the years.