Four layers, in descending order of how reliably they convert:
1. The portfolio. Every other company the fund has backed, and every executive in them. This is the densest and most accessible layer: a portfolio CRO will usually take a meeting from a sister company.
2. Their own operating history. Most investors ran something before they invested. That history is often fifteen years of relationships in exactly one industry, and founders routinely forget it exists.
3. Co-investors. Everyone who shared a cap table with them, and by extension those funds' portfolios. One degree further out, still warm.
4. LPs and advisors. Often large institutions - exactly the enterprise logos an early-stage company cannot otherwise reach. The most valuable layer and the one investors are most careful with.
Because the ask is usually wrong. "Any intros you can make?" puts the work on the investor: they have to recall their network, guess which parts are relevant, and judge whether the ask is reasonable. The honest answer to that question is almost always "let me think about it", which means no.
A board member's network is usually narrower and deeper than an investor's, concentrated in the one industry they spent a career in. They also feel more ownership, which makes them more willing and more protective. Ask them for fewer, better-prepared introductions, and give them more context than you think they need.
The mapping step is the one that is genuinely hard by hand. You are looking for overlaps between a dozen investors and board members, their portfolios and histories, and your target list - across thousands of people, most of whom you have never met.
This is a graph problem, and Orbb treats it as one: investors, board members and executives are traversed alongside your own team, so a route through a co-investor's portfolio CRO surfaces next to a route through your VP of Engineering, scored on the same scale.
Introductions are a currency and the supply is limited. A founder who spends ten investor introductions on poorly-qualified accounts has spent the budget that would have opened the one account that mattered. Spend them on the accounts where the deal is real.