Privacy Startups funded by Y Combinator (YC) 2026

Tinfoil makes it easy to make your AI workloads secure and provably private. You get the privacy of on-prem deployments, while running on the cloud. It's like end-to-end encrypted messaging but for your AI applications. We’ve built a full-stack platform on top of the latest NVIDIA GPUs offering confidential computing capabilities, meaning that you don’t have to trade off performance for privacy. We integrate a suite of recent advances in secure hardware technologies, in particular NVIDIA’s confidential compute mode available on Hopper and Blackwell. When combined with Tinfoil’s software stack, companies can prove their security claims like "we can't see and don’t log your queries.” Tinfoil guarantees that all data always stays private and cannot be accessed by anyone other than the end user -- not even by Tinfoil or the cloud provider it’s processed on. Everything can be made end-to-end encrypted and private with Tinfoil. The founding team combines deep academic and industry experience in security and Internet protocols. Tanya was previously a systems engineer at Cloudflare, where she built Internet security protocols used by billions, and contributed to the Workers AI platform. Jules and Sacha hold PhDs from MIT, where they worked on secure hardware, cryptography, and privacy technologies. Jules has also worked at NVIDIA on their confidential computing team. Tinfoil was born from our personal frustration with the false choice between access to powerful AI and the massive data privacy implications of deeply integrated AI. AI is a universal tool that becomes part of our personal lives and business workflows. In the process, it needs access to all personal, private, and proprietary data. Right now, the only solutions are data processing agreements (i.e., "pinky promises"), band-aids like PII redaction that don't work in practice, or AI locally/on-prem, which doesn't scale. Tinfoil promises to unlock significantly deeper AI adoption and integrations by making it easy to obtain true privacy, just as TLS on the Internet enabled e-commerce to flourish by securing credit cards on the network. Today we offer several self-serve products: - A consumer-facing chatbot that keeps your chats end-to-end encrypted and provides zero-access inference with powerful open-source models like Kimi, Gemma, and GLM. You can try it out for free: https://chat.tinfoil.sh - A developer-friendly API that allows you to build AI applications where all user data is kept private and we as the inference provider cannot see any of the prompts. Our SDKs make sure that all relevant security measures are checked for you before even sending a single byte of data. Learn more:https://docs.tinfoil.sh - An advanced confidential computing platform we call Tinfoil Containers that allows you to secure any Docker application. We make it easy to deploy your own logic and applications inside secure enclaves and prove to the world what code is running inside. This enables attested workloads and publicly verifiable privacy policies for sensitive applications. Learn more: https://tinfoil.sh/containers

Clearly AI automates security and privacy reviews with AI. We performed hundreds of reviews at Amazon and Moveworks and now we're building the product we wish we had. Our users complete reviews in minutes instead of days. Emily and Joe are technical co-founders and senior engineers. We met in 2019 while working on an Alexa security review.

Reality Defender is the market leader in deepfake detection, protecting enterprises and governments from realtime deepfake and agentic fraud. Sign up for free access at https://www.realitydefender.com/api Website: www.realitydefender.com Contact: ask@realitydefender.com YC AMA: https://news.ycombinator.com/item?id=30766050 Awards: 2025 - Gartner: Recognized as Market Leader in Deepfake Detection 2025 - JPMorgan: Inducted into Hall of Innovation 2025 - World Economic Forum: Named Technology Pioneer 2025 - USA DIU + Japan MOD: 1st Place "Global Innovation Challenge" 2024 - RSA Conference: 1st Place “Most Innovative Startup” 2024 - SINET16 Innovator Award 2023 - SXSW 1st Place "Artificial Intelligence, Voice, & Robotics Technologies"

End-to-end privacy, security, and compliance solutions to prepare your organization for emerging AI regulations.

Optery is automated opt out software, and we serve individuals, families and businesses. With Optery, you can remove yourself from hundreds of data brokers that are posting and selling your home address, phone number, email and other private information on the internet. Optery received the “Editors’ Choice” award by PCMag as the most outstanding product in the personal data removal category in 2022, 2023, 2024, 2026 and 2026, the Cybersecurity Excellence Awards for Attack Surface Management, Digital Footprint Management, and Employee Privacy Protection in 2024 and 2025, Cyber Defense Magazine’s Top InfoSec Innovator and Best Attack Surface Management awards in 2024 and 2025, the 2025 Fortress Cybersecurity Award for Privacy Enhancing Technologies, and Fast Company’s Next Big Things in Tech award for security and privacy in 2023. In 2025, Optery was also listed by Business Insider as one of 30 early-stage startups most likely to become a unicorn. Optery prevents phishing and social engineering, identity theft and fraud, online stalking and harassment, ransomware, doxxing, and prevents people's private information from showing up in Google search results. Anyone can create a free account to receive a personalized Exposure Report with live screenshots summarizing where your information is being posted and sold online. Optery then provides free tools for self-service removals, or you can upgrade to a paid plan, and Optery will remove the profiles for you. Optery for Business serves enterprises removing personal information from the internet for their employees and executives, and offers an API enabling application developers to embed data broker scanning and removal technology into their applications.

Feroot (YC W21) is the leading compliance and security platform for b2b websites that helps you easily achieve and maintain compliance with PCI DSS 4.0.1, CCPA, CIPA, HIPAA and 50+ data privacy regulations.

Malloc monitors and prevents anyone from recoding or transmitting data from your mobile device without your knowledge. Malloc uses on-device AI to detect zero-click spyware and abnormal activity and blocks any suspicious communication in real time. We sell this to individuals, enterprises and governments that care about their privacy.

SpruceID lets users control their data across the web. Instead of people signing into platforms, we imagine platforms should sign into people’s data vaults. We implement this pattern into digital wallet ecosystems for governments, enterprises, and blockchains. We believe that architectures that enable individual autonomy in the digital world are necessary for free societies and dynamic economies to thrive.

NuCypher is one of two founding teams of the Threshold Network, which hosts tBTC, TACo, Random Beacon & tUSD. Since 2017, NuCypher has pioneered cryptographic primitives for end-to-end encrypted data sharing, including Proxy Re-Encryption and Threshold Access Control (TACo), novel cryptoeconomic mechanisms (e.g. Stable Yield). and original network/governance architectures (including a historic on-chain merger). TACo, our flagship product, is running on over 120 nodes with ~$80m of associated economic security, has paying adopting developers and major infrastructure partners (Ceramic, Irys, Textile, Unlock), and has been decentralized from genesis (mainnet launch in Jan 2024).

We have hundreds of fully qualified and experienced contractors in Information Security, Cloud Security, Privacy and Compliance available at competitive hourly rates.

As third-party identifiers like the cookie disappear, ad-tech breaks—targeting, frequency capping and measurement disappear. We're rebuilding data infrastructure in advertising to work with cohorts—privacy safe descriptions of users—which enable advertising use cases without the need for sharing personal identifiers. We do this by moving data processing and management out of the cloud, and on to the user's device.

TrueVault builds software tools that help businesses comply with consumer data privacy laws. We believe if businesses have access to products that make getting and staying compliant simple, straightforward, and fully automated, respecting consumers' data privacy becomes the sensible default. And we all benefit from that.

mth sense focuses on finding solutions to "blind" ads. mth sense offers its users an audience library to target certain demographics and psychographics.

Fabric is a personal location-based journal that catalogs experiences and interactions. With Fabric, users can automatically preserve a record of places, paths, activities, add friends, and browse photos.