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The US Supreme Court is weighing a request from Allergan to rule on whether drug companies can pull a medication from the market as generic competition looms in order to force patients to switch to new versions of the drug.

The move, which may hinge on antitrust laws, will be closely watched by the pharmaceutical industry.

Allergan’s request follows a heated battle between the drug maker and New York Attorney General Eric Schneiderman over a tactic known variously as product-hopping or forced switching, which involves pushing consumers from one product to another. A federal appeals court earlier this year ruled that a switch Allergan had planned would harm consumers.

The saga began in early 2014, when Allergan signaled plans to end sales of its twice-a-day Namenda IR tablet for Alzheimer’s disease. The drug maker wanted to pull its drug from the market several months before the patent on the medication was set to expire— and before it faced any competition from generics. Allergan’s plan was to push its newer, once-daily Namenda XR, which has patent protection until 2025.

Schneiderman argued the tactic was “unethical and illegal” because patients would be forced to switch to the newer Namenda XR pill well before lower-cost generics are available for the older drug.

Ultimately, a federal court sided with Schneiderman and ruled that Allergan had to keep its older pill on the market.

Now, Allergan hopes to convince the Supreme Court that the decision is wrongheaded. The drug maker wants the court to send a message that patent holders do not violate antitrust laws when they stop selling a patented product in order to sell another, reformulated version protected under a different patent.

The appeals court decision “affects how drug manufacturers invest today to invent and improve treatments that won’t become available for years or even decades,” Allergan wrote in its 197-page opinion. “By penalizing drug manufacturers who seek to maximize returns on their innovations, the [appeals court] decision… is already chilling critical efforts to develop life-saving medications.”

One legal expert said Allergan is misguided.

“If the Supreme Court takes the case and reverses, it could undercut any future challenges to product-hopping, which could give pharmaceutical companies free rein to engage in this concerning behavior,”  said Michael Carrier, a Rutgers University School of Law professor who specializes in intellectual property.