SAN FRANCISCO — Shares in Qualcomm surged briefly on Monday after Jana Partners, the activist hedge fund, urged the company to consider moves like spinning off or selling its chipset business.

In a letter to investors, Jana argued that the company, whose main operation is a patent-licensing business, has suffered from poor stock performance because investors haven’t recognized its long-term potential. Highlighting the true worth of the company, Jana argued, required potentially drastic steps.

“Over the past several months we have been engaged in a constructive dialogue regarding the steps it can take to restore investor confidence and unlock shareholder value,” Barry Rosenstein, the head of Jana, wrote in the letter.

Jana, one of the most prominent activist investors, disclosed that it had bought more than $2 billion worth of stock, making it one of the company’s larger shareholders.