A recent study published by Consumer Reports (CR) alleges that Instacart has been conducting AI-led dynamic pricing experiments that, in some cases, are drastically inflating the cost of certain products.

CR and its research partner, Groundwork Collaborative, found that the delivery app was conducting these experiments at the platform’s retail partner locations — places like Kroger, Albertsons, Costco, and Safeway. In some cases, consumers were paying as much as 23% more than other shoppers for the exact same product, the report says.

The software involved in the experiments, Eversight, is a SaaS product that offers grocers a retail pricing suite designed to “unlock revenue growth” and capitalize on “pricing solutions that scale your pricing strategy and uncover optimal prices your customers expect.” Instacart discloses on its Eversight page that some shoppers “may see slightly higher prices” than others.

However, as previously noted, some of those price hikes seem slightly higher than “slightly higher.” A 23% price hike isn’t exactly chump change.

When reached for comment, Instacart referred TechCrunch to a previously released statement in which the company noted that “just as retailers have long tested prices in physical stores to understand what resonates with customers, a small subset of our retail partners – 10 U.S. retail partners that already choose to apply markups – use Instacart’s Eversight technology to run limited online pricing tests.” The company also took issue with its activity being referred to as “dynamic pricing,” calling it instead an “AI-enabled pricing experiment.” An Instacart spokesperson said: “These tests are not dynamic pricing – prices never change in real-time, including in response to supply and demand. The tests are never based on personal or behavioral characteristics — they are completely randomized.”

Dynamic pricing has become increasingly common in recent years, and many big e-commerce sites have been accused of employing it. Another recent report claimed that, due to dynamic pricing used by Amazon, school districts across the U.S. have been paying higher prices for basic school supplies. Amazon has since called the report “flawed and misleading.”

This story has been updated with an additional statement from Instacart.