Legal

Cosign privacy policy

Last updated September 2026

At a16z Capital Management, L.L.C. (“a16z”), we take your privacy seriously. Please read this Privacy Policy to learn how we treat Personal Data that we collect through cosign.build (the “Website”). The Website and any tools, features, and functionality offered on or through the Website, including the Cosign platform, are collectively referred to as the “Services.”

By using or accessing our Services in any manner, you acknowledge that you accept the practices and policies outlined below, and you hereby consent that we will collect, use, and share your information as described in this Privacy Policy.

What this Privacy Policy covers

This Privacy Policy covers how we treat Personal Data that we gather when you access or use our Services. “Personal Data” means any information that identifies or relates to a particular individual and also includes information referred to as “personally identifiable information” or “personal information” under applicable data privacy laws, rules, or regulations. This Privacy Policy does not cover the practices of companies we don’t own or control or people we don’t manage.

Categories of Personal Data we collect

Below lists the categories of Personal Data that we collect and have collected over the past 12 months:

  • Contact Information (e.g., name and email address)
  • Account Information (e.g., username and password)
  • Device/IP Data (e.g., IP address)
  • Usage Analytics (e.g., through interactions with our Services)
  • Geolocation Data (e.g., city, state, and IP-address-based location information)
  • Other Identifying Information that You Voluntarily Provide (e.g., identifying information provided in your user profile on the Services or emails or other communications you send us)

Sources of Personal Data

We collect Personal Data about you from the following categories of sources:

  • You. When you provide such information directly to us, or when Personal Data about you is automatically collected in connection with your use of our Services (see “Information collected automatically” below).
  • Other users of the Services. When a user of the Services provides us Personal Data about you, for example, when a user nominates you for a particular cosign.
  • Vendors. We may use analytics providers to analyze how you interact and engage with the Services, third parties to help us provide user support, and customer relationship management service providers.
  • Third-party accounts. If you create an account by connecting a third-party account, such as X, we may collect information from that account, such as your profile information and handle, as permitted by your settings on that platform.
  • Public sources. We may collect Personal Data about individuals, including individuals who have not created an account, from publicly available sources in order to create profiles displayed on the Services.

Personal Data about individuals who are not users

The Services may display profiles about individuals who have not created an Account, using information from public sources or provided by other Users. If you believe we have created a profile about you and you have not registered for an Account, or that content has been inaccurately attributed to you, you may claim that profile, request that we correct it, or request that we remove it, by contacting us at privacy@a16z.com or by using the “Suggest edits” tool available on the Services. We will process such requests consistent with the rights described in the “California Resident Rights” section below, which apply regardless of whether you have created an Account.

Information collected automatically

The Services use cookies and similar technologies such as pixel tags, web beacons, clear GIFs, and JavaScript (collectively, “Cookies”) to enable our servers to recognize your web browser and tell us how and when you visit and use our Services, to analyze trends, learn about our user base, and operate and improve our Services. Cookies are small pieces of data—usually text files—placed on your computer, tablet, phone, or similar device when you use that device to access our Services. We may also supplement the information we collect from you with information received from third parties, including third parties that have placed their own Cookies on your device(s). Please note that because of our use of Cookies, the Services do not support “Do Not Track” requests sent from a browser at this time.

We use the following types of Cookies:

  • Essential Cookies. Essential Cookies are required for providing you with features or services that you have requested. For example, certain Cookies enable you to log into secure areas of our Services. Disabling these Cookies may make certain features and services unavailable.
  • Functional Cookies. Functional Cookies are used to record your choices and settings regarding our Services, maintain your preferences over time, and recognize you when you return. These Cookies help us personalize content, greet you by name, and remember your preferences.
  • Performance/Analytical Cookies. These Cookies allow us to understand how visitors use our Services, including the number of visitors, pages viewed, and time spent viewing pages. They also help us measure the performance of advertising campaigns. The Services may contain Performance/Analytical Cookies from third-party analytics services.

You can decide whether or not to accept Cookies through your internet browser’s settings. Most browsers have an option for turning off the Cookie feature, which will prevent your browser from accepting new Cookies and may allow you to decide on acceptance of each new Cookie. You can also delete Cookies already on your device. If you do this, you may have to manually adjust some preferences every time you visit our Website and some Services and functionalities may not work.

To explore what Cookie settings are available to you, look in the “preferences” or “options” section of your browser’s menu. To learn more about managing and deleting Cookies, please visit allaboutcookies.org.

How we use your Personal Data

We process Personal Data to provide, operate, improve, understand, and personalize our Services. We also collect and use Personal Data for the following purposes:

  • To meet or fulfill the reason you provided the information to us.
  • To communicate with you about the Services, including Service announcements or updates.
  • To operate community features of the Services, including profiles, questions and answers, cosigns, and lists.
  • To provide support and assistance for the Services.
  • To create and manage your account or other user profiles.
  • To personalize website content and communications based on your preferences.
  • To deliver emails and other communications.
  • To respond to user inquiries and fulfill user requests.
  • To improve and develop the Services, including testing, research, analysis, and product development.
  • To protect against or deter fraudulent, illegal, or harmful actions and maintain the safety, security, and integrity of our Services.
  • To comply with our legal or contractual obligations, resolve disputes, and enforce our Terms of Use.
  • To respond to law enforcement requests and as required by applicable law, court order, or governmental regulations.
  • For any other business purpose stated when collecting your Personal Data or as otherwise set forth in applicable data privacy laws, such as the California Consumer Privacy Act (the “CCPA”).

We will not collect additional categories of Personal Data or use the Personal Data we collected for materially different, unrelated, or incompatible purposes without providing you notice. We only use sensitive Personal Data as permitted by applicable laws, including the CCPA, or otherwise with your consent.

We may communicate with you if you’ve provided us the means to do so. If you do not want to receive communications from us, please indicate your preference by emailing privacy@a16z.com.

We may use automated or algorithmic tools, including those offered by third-party service providers, to process your Personal Data as needed to help operate, provide, maintain, and improve the Services and support our internal processes.

We may create aggregated, de-identified or anonymized data from the Personal Data we collect, including by removing information that makes the data personally identifiable to a particular user. We may use such data and share it with third parties for our lawful business purposes, including to analyze, build, and improve the Services and promote our business, provided that we will not share it in a manner that could identify you. We will not attempt to re-identify de-identified data, other than to determine whether our de-identification processes satisfy applicable law.

How we share your Personal Data

We disclose and over the past 12 months have disclosed your Personal Data described above to the following categories of third parties:

Service providers

Categories shared: All categories of Personal Data.

Purposes: Third-party service providers help us provide the Services and operate our business, including ad networks, email service providers, analytics providers, security and fraud prevention providers, automated or algorithmic providers, hosting and other technology and communications providers, and staff augmentation and contract personnel. They may only use your Personal Data for specific purposes relating to assisting us with running our business.

Users of the Services

Categories shared: Contact Information and Other Identifying Information that You Voluntarily Provide.

Purposes: We may share your Personal Data with other users of the Services at your direction as needed to provide the Services.

Prospective employers and other recipients

Categories shared: Contact Information and Other Identifying Information that You Voluntarily Provide.

Purposes: If the Services offer a feature to privately signal interest in a person, company, or job opportunity, we may share information about that signal with the applicable person, company or prospective employer at your direction.

Successors to our business

Categories shared: All categories of Personal Data.

Purposes: Your Personal Data may be transferred to a third party if we undergo a merger, acquisition, bankruptcy, or other transaction in which that third party assumes control of our business, in whole or in part.

Data security and retention

We seek to protect your Personal Data from unauthorized access, use, and disclosure using appropriate physical, technical, organizational, and administrative security measures based on the type of Personal Data and how we are processing it. The Services use industry-standard Secure Sockets Layer (SSL) technology to allow for the encryption of Personal Data you provide to us. You should also help protect your data by selecting and protecting your password or other sign-on mechanism, limiting access to your device and browser, and signing off after accessing your account. No method of transmitting or storing data is completely secure. Except as expressly required by law, we are not responsible for theft, destruction, loss or inadvertent disclosure of your information or content.

We retain Personal Data about you for as long as is reasonably necessary for the business purposes specified in this Privacy Policy, based on criteria such as whether retention is necessary to maintain our relationship or provide the Services, comply with legal obligations, resolve disputes or collect fees owed, enforce contractual agreements, protect our rights, property or business, or is otherwise permitted or required by law. We may further retain information in an anonymous or aggregated form where it would not identify you personally.

Personal Data of children

We do not knowingly collect or solicit Personal Data about children under 13 years of age. If you are a child under 13, please do not attempt to use the Services or send us Personal Data. If we learn we have collected Personal Data from a child under 13, we will delete it as quickly as possible. If you believe a child under 13 may have provided Personal Data to us, please contact privacy@a16z.com.

California resident rights

If you are a California resident, you have the rights set forth in this section. These rights are not absolute, and in certain cases we may decline your request as permitted by law. If there is a conflict between this section and another provision of this Privacy Policy, the portion more protective of Personal Data shall control. Questions may be sent to privacy@a16z.com.

Access

You have the right to request information about our collection, use and disclosure of your Personal Data, including the categories collected and disclosed, sources, purposes, categories of third parties, and specific pieces of Personal Data collected about you.

Deletion

You have the right to request that we delete the Personal Data that we have collected about you.

Correction

You have the right to request that we correct any inaccurate Personal Data that we maintain about you.

Exercising your rights

To exercise these rights, send us a request that provides sufficient information to verify that you are the person about whom we collected Personal Data, or an authorized agent, and describes your request in sufficient detail for us to understand, evaluate and respond to it. We will only use Personal Data provided in a valid request to verify your identity and complete your request.

We will work to respond within 45 days. We will not charge a fee unless your request is manifestly unfounded or excessive. If a fee is warranted, we will notify you and explain the decision before completing your request.

Submit a request by emailing privacy@a16z.com. You may authorize an agent to exercise your rights on your behalf; we may request a copy of your written permission. We will not discriminate against you for exercising your rights under the CCPA.

Changes to this Privacy Policy

We’re constantly trying to improve our Services, so we may need to change this Privacy Policy from time to time. We will alert you to changes by placing a notice on the Services, sending you an email and/or by some other means. If you’ve opted not to receive legal notice emails, or haven’t provided an email address, those legal notices will still govern your use of the Services. If you use the Services after changes have been posted, that means you agree to the changes. Use of information we collect is subject to the Privacy Policy in effect at the time such information is collected.

Contact information

If you have questions or comments about this Privacy Policy, how we collect and use your Personal Data, or your choices and rights, please contact us at privacy@a16z.com.