PepsiCo’s Tropicana Pure Premium will start carrying a label early next year notifying shoppers that the orange juice does not contain genetically modified organisms.

That might seem like a big win for advocates of GMO labeling. But in the case of Tropicana, it’s a far more complicated issue, with some viewing the move by PepsiCo (PEP) as insincere.

There is currently no such thing as a genetically modified orange on the market. Any product that is 100% orange juice, including Tropicana Pure Premium, is automatically non-GMO. It’s a little bit like labeling oranges gluten-free.

“It’s obviously disingenuous to call a product for which there is no GMO counterpart non-GMO,” says Gary Hirshberg, chairman and co-founder of pro-GMO labeling group Just Label It and chairman and co-founder of Stonyfield Farm. “This doesn’t increase transparency. It obfuscates and adds confusion at a time when all of us—corporations, food companies—ought to be committed to clarity and simplicity in our messaging.”

PepsiCo declined to comment for this article.

Products like orange juice are considered “low risk” for GMOs, says Megan Westgate, executive director of the Non-GMO Project, whose seal Tropicana will carry. But she points out that there may well be GMO oranges on the market in the near future. “Testing [of GMO varieties] is is being done on everything,” Westgate says, including oranges, with a genetically engineered citrus tree resistant to citrus greening undergoing testing. Most consumers also don’t know which ingredients have GMO counterparts, Westgate says.

Hirshberg acknowledges that PepsiCo is not the first company to use the non-GMO seal on a product that doesn’t need one, but he believes that the soda and snacking giant is guilty of what he calls “Orwellian corporate double speak.”

According to the Environmental Working Group, PepsiCo was the No. 3 biggest spender (behind Monsanto (MON) and DuPont (DD)) in dispensing $8.8 million to overturn state labeling initiatives. Meanwhile, PepsiCo has supported federal legislation that would make GMO labeling optional.

This is a case of “corporate schizophrenia,” says Marion Nestle, a professor of nutrition and food studies at New York University. PepsiCo is trying to appear transparent, she says, but “they are doing everything they can behind the scenes” to block mandatory labeling.

Sales of 100% juice have stayed relatively flat over the past five years as consumers have become more concerned by their sugar intake. Sales of Tropicana, the No. 1 brand, have fallen by about 25% between 2009 and 2014, according to Euromonitor.

PepsiCo’s decision to pursue a non-GMO label for Tropicana may be part of an attempt to reignite sales since the Non-GMO Project Verified seal is one of the fastest-growing labels. “This is a marketing device” for PepsiCo, says Nestle.

Consumers have increasingly been calling for transparency when it comes to what they eat. In 2010, products carrying a non-GMO label generated $348.8 million in sales, according to data tracker SPINS. For the 52 weeks ending September, that figure jumped to $15 billion.

The Non-GMO Project’s Westgate says that in the last 12 months there’s been a huge shift as some of the largest consumer packaged goods companies in the country have started to pursue non-GMO labels. Previously these efforts were reserved for natural and organic brands.

To read more about the issues facing legacy food companies, read Fortune‘s “War on Big Food” cover story from May.