Ashton Kutcher is under fire from CBS after promoting social media companies Foursquare, Flipboard, Hipmunk, GroupMe and Chegg on Monday night's episode of Two And A Half Men.

The actor/social media maven holds investment stakes in all five companies. On Monday, he put stickers for the brands on character Walden Schmidt's laptop, and CBS is upset because the network received no compensation for the product placement.

"This was not part of any advertising transaction with CBS," a network rep said. "Our policy is to disclose such financial interests in a credit at the end of the broadcast."

But, The Hollywood Reporter says, the network has decided not to take any action against Kutcher -- though it will blur the stickers from future episodes.

This marks more bad news for Ashton, who is in the middle of a tabloid tornado this week as rumors are swirling that he's been cheating on wife Demi Moore.

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