For years, Warner/Chappell Music company has collected more than $2 million in royalties annually for the copyrights to "Happy Birthday to You." Like everything else, intellectual property (intangible property) may be owned. For nearly the last century, Warner/ Chappell and other companies have bought and sold ownership and enforced their ownership.
Finally, someone challenged this, which is not surprising. Lo and behold, a court in California determined last week that no one owns Happy Birthday. In fact, Warner/Chappell Music now has to repay millions that they "earned" from enforcing the copyright.
So feel free to sing away at the next birthday party without fear of being sued!