Let’s say you are in a car dealership, and a sedan’s window sticker says: “$25,000 for buyers under age 30, $50,000 for anyone older.”

That probably doesn’t seem like a reasonable way to price automobiles. But the dating app Tinder didn’t hesitate to charge older subscribers more to seek romance online.

Some over-30 Tinder subscribers sued, arguing that the app’s pricing model violates California’s Unruh Act, which bans discrimination on the basis of age, race, gender, national origin and other “personal characteristics.”

The Los Angeles Superior Court ruled against the unhappy subscribers. But the California Court of Appeal swiped left on the lower court’s ruling in a recent decision (Candelore v. Tinder, Inc.), sending the case back for trial.

Tinder, Inc. operates the smartphone-based dating app Tinder. Users see photos and brief information about potential dates, and swipe right to express approval (interest in dating the person) or left for disapproval. If the person in the photo also swipes right, the two are matched for a possible date.

The app is free for those who are content with its basic services. Tinder Plus, with extra features, costs $9.99 per month for those under age 30, but for older users the price is twice as much at $19.99.

In press articles cited in court filings, Tinder defended this age-based pricing. “During our testing we’ve learned, not surprisingly, that younger users are just as excited about Tinder Plus, but are more budget constrained, and need a lower price to pull the trigger,” a Tinder executive told a news outlet.

In court, the company argued that its age-based pricing is not arbitrary or unfair, and is lawful because it is not based on “the irrational, invidious stereotypes that the Unruh Act was intended to proscribe.”

Tinder insisted it is not discriminating on the basis of age, but instead is using a pricing model that “rationally treats youth as a reasonable proxy for economic disadvantage.”

It is “self-evident that people under 30 face financial challenges,” it said, and this “common knowledge provides a reasonable and non-arbitrary basis for Tinder to offer a discount to people under 30.”

That was good enough for the lower court, which sustained Tinder’s demurrer (that is, it ruled that plaintiff Candelore had not established sufficient legal basis for his complaint.)

The differential pricing was not an “unfair” practice in violation of the Unruh Act, the trial judge ruled, because it gave more consumers access to the offered services, and also allowed “profit maximization by the vendor, a legitimate goal in our capitalistic society.”

But the appellate court didn’t see it that way. After all, not all prospective Tinder users under 30 are financially disadvantaged, and not everyone over 30 is rolling in cash.

Age discrimination may violate the Unruh Act “if used as an arbitrary class-based generalization,” the appellate court said.

Operators of retirement homes are allowed to have age-limited admission policies, it noted, because of the special housing needs of the elderly. And some age-related pricing discounts, such as offering seniors and children reduced prices for movie theatre tickets and bus fares, are allowed by specific California statutes.

“The danger of using age as a proxy for income to justify age-discriminatory pricing becomes more apparent when one acknowledges that such pricing operates not merely as a discount for the favored age group, but effectively as a surcharge on the disfavored one,” the appellate court said.

“It is inconceivable,” it added, “that an antidiscrimination law like the Unruh Act would countenance a grocer charging an unemployed 31-year-old patron twice as much as an employed 28-year-old customer” merely because market research showed those over 30 “as a group” generally earn more than 18-to-29-year-olds.

Profit maximization is a legitimate business objective which can be advanced by price discrimination, such as offering different features at different price points, or by reducing prices during a sale. However, maximizing profits “can never serve as an excuse for prohibited discrimination among potential customers,” the court said.

Tinder, the justices noted, could have offered different membership levels at prices that attracted budget-conscious users and, with additional features, appealed to users willing to pay more – all without discriminating among users on the basis of age.

Concluding that the lower court erred in preventing the plaintiff from pursuing his lawsuit, they sent the case back for a full trial, awarding Candelore his costs on appeal.

By Rachel E. Balchum