I practically rewrote every IP "agreement" for nearly every job I had since I started working in industry (ca. 1965). The terms were more or less as follows.
1. I am in the business of invention. I invent many things. I cannot possibly disclose all of them. Hence, ANYTHING I have done in the past is excluded and ANYTHING I will do after I leave your employ is excluded without having to be disclosed. This is true even if the thing invented can be construed to be directly or indirectly connected to your business. The only exception to this will be those things directly and explicitly connected to your IP disclosed to me during my employ for a period not to exceed two years after my departure for un-registered un-patented IP. Normal patent and copyright laws apply - BOTH ways.
2. What I do 0n your time with your equipment on projects specifically assigned to me is yours.
3. What I do on my time with my equipment on my self assigned projects distinct from yours is mine.
4. Since my business is invention, if the invention was concieved on your premises but is not DIRECTLY connected to your business, your disclosed IP, and your assigned project, the invention is mine. This will be true even if the invention is used to indirectly support project. In that case, a non-exclusive license to use will be granted by me to you but I still own the resultant IP.
Almost without exception, the terms were accepted. Where there was substantial disagreement, I looked for another job/contract.
What size employers? I'm finally understanding that basically everything is open to negotiation with smaller organizations. However, many large organizations have stock contracts on their Intranet which you e-sign, and there's literally nobody to negotiate with. Plus, if you decline to sign, they'll happily find another employee, since they've got too many already.
I did it with large and small. The largest one was General Motors (ca 1998). I negotiated the IP agreement with my first industrial employer. I didn't get all the terms I asked for but I did get enough to make it worth while to sign.
An additional requirement might be that you actually have to be an inventor with a proven track record. If your proven record and skill set is indistinguishable from millions other workers, you are hosed no matter what. You have to take what you can get. In that case, it doesn't matter because you have no IP to protect anyway.
Most IP agreements are written by lawyers who arrange the terms to be totally one sided. Your employer is to have absolute claim over the entire contents of your life. THAT is simply unacceptable. Yes, you need a job but the employer needs someone who can do the work as well. You don't have to agree to be a rightless drone. A job like that is not worth having.
You have the right to pursue your skill to make a living. An employer does not have the right to prohibit that. Ask for terms that respect BOTH your and your employer's rights and you are likely to have them accepted.
1. I am in the business of invention. I invent many things. I cannot possibly disclose all of them. Hence, ANYTHING I have done in the past is excluded and ANYTHING I will do after I leave your employ is excluded without having to be disclosed. This is true even if the thing invented can be construed to be directly or indirectly connected to your business. The only exception to this will be those things directly and explicitly connected to your IP disclosed to me during my employ for a period not to exceed two years after my departure for un-registered un-patented IP. Normal patent and copyright laws apply - BOTH ways.
2. What I do 0n your time with your equipment on projects specifically assigned to me is yours.
3. What I do on my time with my equipment on my self assigned projects distinct from yours is mine.
4. Since my business is invention, if the invention was concieved on your premises but is not DIRECTLY connected to your business, your disclosed IP, and your assigned project, the invention is mine. This will be true even if the invention is used to indirectly support project. In that case, a non-exclusive license to use will be granted by me to you but I still own the resultant IP.
Almost without exception, the terms were accepted. Where there was substantial disagreement, I looked for another job/contract.