LoREnc: Low-Rank Encryption for Securing Foundation Models and LoRA Adapters

LoREnc is a training-free framework securing foundation models and LoRA adapters via spectral truncation of dominant weight components, compensation embedded in authorized adapters, and orthogonal reparameterization to hide structural fingerprints. Requires no retraining or original dataset access, addressing a key gap in existing IP-protection methods. Relevant to enterprises deploying proprietary fine-tuned models on-device.