The Launch of Cosign,
from the outside.
a16z built a private network around personal recommendations.Explore who was granted access from its launch.
Looking back
Who shaped your career?
The person whose help made a difference.
The Launch of Cosign,
Filter the people. Build your own graph.
Explore the launch
How to explore
Drag space to pan. Scroll or pinch to zoom. Select a portrait to inspect; select a line for its source. Focus connections to build a smaller graph. Back restores your previous view.
Opening the launch network…
What’s a Cosign worth?
Inside the launch ↗Who says it. What they know. What they put behind it.
A shared employer reveals overlap. A personal recommendation reveals judgment. Cosign asks for three kinds:
Right now
Who would you work with anywhere?
Someone you would choose to work with.
Looking ahead
Who’s a person to watch?
Belief before the outcome is obvious.
Questions worth asking
What the launch establishes—and what remains open.
Sources & method
999 public profiles captured September 26, 2026. Directory claims retain their source; researched relationships link to the record supporting them.
Company overlap does not establish acquaintance. A public recommendation records one person’s judgment. Neither proves an invitation or a private Cosign.
Research coverage is not the boundary of what public research can discover. The distinction here is between observing an existing record and asking someone to make a new, explicit judgment.