Give them a bigger carrotIn this case the new carrot is all those delicious delicious orphaned works already written and ripe for being monetized. All that needs to happen is go from a blanket 'everything is copyrighted forever minus a day' and move into a 'you want it kept copyrighted? fine you get twenty years no questions asked. then you have to keep registering every five or ten years.' Corporations could afford to do this. It would also allow works that were not in their day profitable to fall into public domain if the author does not wish to retain rights.
Granted I'm not sure how we would transition into said system without headaches but on the face of it the concept looks like it'd be a win for everyone. Potential childhood memories and inspiration that might not be profitable enough to maintain gets put out for you to make your own spin on. Hollywood, the music industry, and whoever, gets to mine out the now expanded public domain for ideas and concepts.
Remember, Disney got started with fairy tales not only because obvious children's stories but it's something everybody knew and had in some form or another grown up with..
What's there to say a company won't just keep rights to a thing Forever then?
Possibly nothing, but considering the bloat generated by keeping up with unused works verses the resources freed in letting it go might be reason enough.
Strengthening Non-Commercial RightsAnother idea is to strengthen the rights to create non-profit fan-works; fan-fiction, web series, and so forth. Take Nuka Break for example, or Star Trek Continues. Fan series based on existing properties with no money being made. The parent companies are OK with that, but the current assumptions are it's illegal and the parent company has full right to slap a CnD on you whether it be hours after you've started work or months after momentum has started building.
Yes strengthened non-commercial rights would lead to applications parent companies might not like (see also Disney clamping down on a Lion King Mush basically because, as rumor went, it was a text based incest and bestiality pit...) but if the viewer cannot tell that a thing is not an official work or not then that's the viewer's problem. after all misrepresenting yourself as part of an entity you're not is still fraud no matter the reason.
I like Kindle Worlds as a concept. Lets you Monetize fan works with the understanding that concepts you put forward could be folded in with no credit or compensation. Except I also like the fanfiction.net model. Post whatever you like but you make nothing. Mind you fanfiction.net has no real 'rights'' or negotiation leverage so the whole site could be shut down, and occasionally purges 'explicit' material.
Basically my logic is as follows:
Is money being made off this derivative?
if no then 'is person claiming affiliation with rights holder or in other way suggesting they are working under official capacity?'
if no then let it roll because free advertisement.
if yes to either statement then summon lawyers.