Contact Cosign

For help with your account, your profile, the Cosign Chrome extension, or anything else on Cosign, email cosign@a16z.com. Include a brief description of the issue and your profile link, if relevant, so our team can understand what you need.

If something is not working, describe what you were trying to do, which page you were on, and what happened. Mention whether you were using the website or the Chrome extension. Do not include passwords, sign-in codes, or other account credentials in your message.

For questions about personal data or your privacy choices, email privacy@a16z.com. Our privacy policy explains how to submit a privacy request and the information needed to process it.

You can also visit Support or read the FAQ. Legal notices and the applicable mailing instructions are described in our terms of service.