Hampton Creek's stated mission is to produce healthy, sustainable and affordable food products.

According to the Food and Drug Administration, it's also misleading consumers by labeling its line of vegan spreads "Just Mayo."

The crux of the issue hinges on eggs. True mayo must contain them, the FDA stipulates. Hampton Creek's line of "Just Mayo" spreads does not, and thus the name is a misnomer at best, misleading at worst. The FDA is making it very clear it's not amused by Hampton Creek's antics, writing in an Aug. 12 warning letter to the company:

"Just" together with "Mayo" reinforces the impression that the products are real mayonnaise by suggesting that they are "all mayonnaise" or "nothing but" mayonnaise. However, your Just Mayo and Just Mayo Sriracha do not meet the definition of the standard for mayonnaise. According to the labels for these products, neither product contains eggs. Additionally, the products contain additional ingredients that are not permitted by the standard of identity for mayonnaise, such as modified food starch.

This is not the first time Hampton Creek has been the target of an egg-based lawsuit. Last year, Unilever (which owns the prominent mayonnaise brand Hellmann's) sued the company over false advertising and unfair competition arguing, essentially, what the FDA is laying down: no eggs, no mayonnaise.

In December, Unilever dropped the lawsuit, perhaps in part because of a Change.org petition asking the company to "stop bullying" the startup, which collected more than 112,000 signatures.

Is the FDA perhaps being a tad oversensitive? After all, its definition of mayonnaise hasn't been updated since the 1950s, when a vegan diet was a mere twinkle in the eyes of the mainstream public. Should Hampton Creek really have anticipated that the FDA would cleave so thoroughly to the egg requirement?

Related: Hampton Creek Reinvents the Egg

Absolutely, according to Ivan Wasserman, an attorney at Manatt Phelps & Phillips. "What's surprising is that it took this long. As far as having to comply with the standards of identity, I'd say the FDA has a very strong position," he told The Washington Post. For the record, when advertising the Just Mayo brand on its site, Hampton Creek does not explicitly state that the product is eggless.

In its letter, the FDA also takes issue with Hampton Creek's claim that its Just Mayo spreads are cholesterol-free. (To advertise with that label, the agency dictates that food cannot contain "more than 13 grams of total fat per 50 grams".)

"Failure to promptly correct these violations may result in regulatory action without further notice, such as seizure and/or injunction," the FDA warns.

While the FDA's meddling has the potential to cause a series headache for Hampton Creek, it could also be a great marketing opportunity. Just as with the Unilever lawsuit, Hampton Creek is not only able to play the scrappy underdog in a fight with a larger foe (in this case, federal regulators), but it gets the opportunity to spotlight its product and educate consumers about the health and environmental benefits of eggless mayo.

Or, eggless…sandwich spread? This is where things get tricky for the company -- if the FDA is successful, and Hampton Creek must change its product's name, are there really any good alternatives?

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