One of the chief concerns that some in the music industry have about digital-locker services is that at least a couple of them allow all songs, even pirated tunes, to be stored in the cloud.

Before music owners store their songs in the cloud, do they need to pay the music labels

Thomas Hesse, digital chief for Sony Music Entertainment, said as much at the Midem conference in France on Saturday, according to Billboard.

"We are very uncomfortable with a model where you can just throw anything into the cloud and stream it, if what you threw into the cloud was not legitimately purchased," Hesse said during a panel session. "It's not the right thing to do to launch a service under these kinds of shady legal situations. We will do everything in our power to enforce our rights in those kinds of situations."

Cloud music services, such as mSpot and MP3tunes.com, enable digital music owners to store songs on their servers and access them via Web-enabled devices. Cloud music is the wave of the future, or at least that's what many predict. Apple and Google spoke to the labels last year about the possibility of building their own offerings.

Nobody knows for sure if consumers will take to the cloud services. On the periphery of all the hype is a controversy over whether these services must acquire licenses from the major labels to operate legally. If the services aren't obligated to seek permission, then the labels could find themselves cut out of cloud music.

Participating on the same panel with Hesse was Daren Tsui, CEO of mSpot, a locker service that launched without the labels' blessing. So, Hesse wasn't just blowing off steam. He was sending a message. (Centuries ago, men would slap each other in the face with empty gloves to signal they were ready to fight. The modern equivalent is to issue thinly veiled legal threats during a conference panel.)

According to Billboard, Tsui responded to Hesse's throwing down of the gauntlet with a terse: "It's not our job to police how [consumers] get their music."

As for the law, it's unclear whether cloud services need the labels' permission to operate. There's not yet a legal precedent, as Billboard writer Anthony Bruno correctly pointed out. But we could have one soon.

EMI, the smallest of the four largest record companies, filed a copyright lawsuit in 2007 against MP3tunes.com, the locker service launched by Michael Robertson, founder of pioneering locker service MP3.com (now owned by CBS, parent company of CNET).

EMI said its suit has nothing to do with protecting cloud turf and everything to do with simple copyright violations. EMI alleges that MP3tunes.com encourages people to pirate music via a search engine owned by Robertson, Sideload.com. EMI claims that Robertson then offers his customers a place to stash their illegally obtained songs: MP3tunes.com.

Robertson said that his lawsuit is part of an attempt by EMI and the other top labels to charge people to store previously purchased songs' a double dip.

In response to Hesse's comments, Robertson told CNET: "I'm uncomfortable with a model in which record labels demand payments forever from consumers who want to listen to their personal collections online and on any device they own. I'd also remind Mr. Hesse and others in the music business that storing music collections online is specifically allowed by the DMCA."

A federal court judge in New York is supposed to decide the case between EMI and Robertson sometime this year.