The US Supreme Court will decide on whether to bar doctors from being pitched drugs depending on their prescription habits from name-brand pharmaceutical companies.
The landmark case puts the US state of Vermont against companies that have sold prescription information to drug makers, a practice known as 'data-mining', without prior consent of the doctors.
Although the state has a law to prohibit data-mining, companies that sell the information claim they put valuable drug information into the hands of physicians and a ruling against them would be against their freedom of speech.
Vermont had countered this argument by claiming that the practice violates patient-doctor confidentiality and that it is increasing the cost of prescription drugs, a stance supported by the Obama administration.
The Supreme Court began hearing cases on 26 April, with a decision expected by late June this year.