https://www.by4si.com/ 2026-07-26 https://www.by4si.com/assets/home-products/presence-key-array-tile.jpg Presence Key physical authority interface studies An array of current Presence Key physical-form studies. https://www.by4si.com/strategy-2033 2026-07-25 https://www.by4si.com/assets/presence-key-v2/key-handoff.jpg 4SI Strategy 2033 personal physical trust anchor A Presence Key concept device being placed into a person's hand. https://www.by4si.com/presence 2026-07-20 https://www.by4si.com/assets/product-studies/key-system.jpg Presence Key physical trust system Presence Key and its controlled verification system. https://www.by4si.com/presence/key 2026-07-26 https://www.by4si.com/assets/product-studies/key-access.jpg Presence Key human authority verification A Presence Key product study at a controlled institutional verification point. https://www.by4si.com/presence/layer 2026-07-20 https://www.by4si.com/assets/editorial/product-authenticity.webp Presence Layer physical object verification Physical verification supporting product and component authenticity. https://www.by4si.com/presence/home2026-07-20 https://www.by4si.com/evidence2026-07-27 https://www.by4si.com/applications 2026-07-19 https://www.by4si.com/assets/editorial/product-authenticity.webp Physical product authenticity verification Physical verification supporting product authenticity and chain of custody. https://www.by4si.com/intelligence2026-07-28 https://www.by4si.com/authority-test2026-07-24 https://www.by4si.com/presence-moment2026-07-23 https://www.by4si.com/company 2026-07-27 https://www.by4si.com/assets/founder/niclas-braun-study.jpg Niclas Braun, founder of 4SI https://www.by4si.com/company/niclas-braun 2026-07-20 https://www.by4si.com/assets/founder/niclas-braun-study.jpg Niclas Braun, founder and CEO of 4SI Niclas Braun, technology entrepreneur and founder and CEO of 4SI. https://www.by4si.com/papers2026-07-28 https://www.by4si.com/physical-evidence-gap 2026-07-28 https://www.by4si.com/assets/editorial/critical-infrastructure.webp The Physical Evidence Gap Physical verification at a consequential operational boundary. https://www.by4si.com/verification-control-primitive2026-07-19 https://www.by4si.com/physical-trust-digital-physical-boundary2026-07-21 https://www.by4si.com/economic-research 2026-07-19 https://www.by4si.com/assets/editorial/natural-delta-signature.webp The economics of verifiable reality A branching natural system illustrating physical origin and distributed pathways. https://www.by4si.com/brand2026-07-26 https://www.by4si.com/approach2026-07-19 https://www.by4si.com/faq2026-07-19 https://www.by4si.com/glossary2026-07-19 https://www.by4si.com/careers2026-07-19 https://www.by4si.com/founding-institutions2026-07-20 https://www.by4si.com/presence-exposure-assessment2026-07-27 https://www.by4si.com/contact2026-07-19 https://www.by4si.com/access2026-07-19 https://www.by4si.com/responsible-disclosure2026-07-26 https://www.by4si.com/legal2026-07-26 https://www.by4si.com/legal/legal-notice2026-07-26 https://www.by4si.com/legal/privacy-research2026-07-26 https://www.by4si.com/legal/privacy-eu-eea2026-07-28 https://www.by4si.com/legal/privacy-us2026-07-28 https://www.by4si.com/legal/california-privacy2026-07-28 https://www.by4si.com/legal/presence-risk-index-disclaimer2026-07-26 https://www.by4si.com/legal/exposure-radar-disclaimer2026-07-26 https://www.by4si.com/legal/editorial-source-policy2026-07-26 https://www.by4si.com/legal/corrections-policy2026-07-26 https://www.by4si.com/legal/copyright-takedown2026-07-26 https://www.by4si.com/legal/ai-editorial-transparency2026-07-26 https://www.by4si.com/legal/accessibility2026-07-26 https://www.by4si.com/legal/legal-privacy-contact2026-07-26 https://www.by4si.com/privacy2026-07-28 https://www.by4si.com/cookies2026-07-26 https://www.by4si.com/terms2026-07-26