You can try B-Z permissions, but really, most of these guys are just doing it without any legal clearance, they are eiher blissfully unaware of their untenable legal standing or are gambling that they are too small to be noticed and dealt with. But really, is anything truly obscure on the internet, thanks to search engines? It just takes one P.O.'d lawyer at some reception....
If I was an unscrupulous person, I could make a fine second income, just surfing these online wedding demos all day, and ratting them out to the record companies and RIAA for a bounty. Or just doing it to tie up a lot of my competition and set them back, if I was still doing weddings myself.
Why deliberately put yourself in those cross-hairs? That's why I'm glad you're asking the right questions before making the same mistakes as your competition.
There used to be a buy-out collection on the market that changed popular movie & tv themes just enough to get around copyright, making them legally new compositions, but sounding nearly identical to the originals. I don't remember the name, or know if it's still being produced. When I was still doing weddings I, like nearly everyone else, and every DJ in the world, used popular music at will, because that's what our clients wanted and expected to hear. Nowadays I'm more careful to use buyout libraries for my documentary work. I remember some years ago there was an attempt by the music industry to try to go after DJs for playing popular music, but I think they realized quickly that doing so was a lose-lose proposition for them. Not that I don't have respect for copyrights, but I do think there is a tacit understanding within the music industry, public pronouncements to the contrary notwithstanding, that small independents and DJs who are not producing for broadcast or theatrical release are not hurting them, and may actually be helping them by continuing to popularize their music. Judging by their lavish lifestyles, I don't think anyone on this level is causing them any grief.
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