EIR = entrepreneur-in-residence. I think the term was lifted from other in-residence conventions. It sounds good, and even curious. In fact, most people have no idea what an entrepreneur-in-residence is, why it is, who it is, what it does, for how long, for how much, for who, with who, and what it means.
EIRs are often executives coming either off of big win exits or long-time big company jobs that have served some sort of scale or meaningful inflection. Often these are folks that VCs feel safe to bet on or place in a portfolio company that's in need of a "proven" executive. It seems even more so the entrepreneur has operated in a portfolio company of the VC. Actually, sometimes the term refers to "executive-in-residence", tailored to distinguish from those that start companies from those that scale companies. In any case, I don't know this role to be one that can be solicited. In my experience its one you kind of have to get the "call" for. Typically there would be a "sponsor" of sorts, someone in a VC firm that represents the industry the entrepreneur is in, and that can vouch for the entrepreneur, and that is willing to potentially put money behind the entrepreneur (right now I'm wondering how many times I can say entrepreneur in the same sentence...).
EIRs tend to get a VC business card, and are encouraged to scour their network and the VCs network to soak up the rays from smart people. It's what you make of it in that first inflection. Ok, so this might sound bitchin' to many of you, but there is a monkey on the back of the EIR. This mode can't sustain, and there must be goods harvested in due time. How much time? It's often vague/open ended. Some say it's 90 days, some say about six months. EIRs ultimately ought to find a home in a portfolio company or 'found' a new one of their own, which the arrangement suggests, the VC has first dibbs on funding. Rightfully so, since they're paying the EIR money to think and figure things out, and in many cases helping think thru idea theses.
Sometimes EIRs don't gel with the VC or don't produce ideas in alignment with the VC. That's ok; everyone is usually happy to go home at that point. Best case, minds meld and new companies emerge. At that point, who's idea is it? It's usually the entrepreneur's idea with influence from the VC along the way, so it's ultimately co-ownership. So if there's a funding, the VC already owns some of the company before equity is even dealt. Fair, since the VC has invested the dollars on the EIR to get to that point.
I've talked to many EIRs who suffer trying to fit into the box of the VC that sponsored them. Others hoped they could sit in on more pitches and actually become a VC. Others don't have a lick of creativity and wish to discover a diamond in the rough in the process. And of course many thrive in new found companies. There are different strokes for different folks.
In the end, it's a good deal for the EIR because it's a great way to validate ideas and finance a company with a biased source. And it's good for the VC because there's risk taken out of a promising new company.