iHeartMedia Inc. is preparing to file for bankruptcy as soon as this weekend after months of negotiations with creditors who hold over $15 billion of the company’s debt, according to people familiar with the matter.

The nation’s largest radio-station operator, its private-equity owners Bain Capital and Thomas H. Lee, and its lenders and bondholders are still in talks and there is still a possibility of striking a forbearance agreement that would delay a bankruptcy filing until after the weekend, the people said.

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