Clumio, a data backup and recovery provider for companies using the public cloud, has raised $75 million in a Series D round of funding. The problems that Clumio, and others like it such as Veeam and Rubrik, are trying to solve are manifold. While public cloud spending is showing little sign of weaning, businesses also face growing threats related to ransomware, with extortion gangs enjoying a bumper 2023 by most estimations.