Earendil Labs signed an exclusive pact with WuXi XDC to license the WuXiTecan‑2 payload‑linker platform and tap WuXi XDC’s CRDMO capabilities to advance antibody‑drug conjugates (ADCs). The deal carries up to $885 million in combined upfront and milestone payments plus tiered royalties, and pairs Earendil’s AI‑driven bispecific biologics pipeline with WuXi XDC’s linker chemistry. Earendil framed the arrangement as strategic to accelerate its bispecific and multispecific ADC programs, including CEACAM5/CDH17 and TROP2/PDL1 candidates. WuXi XDC will support manufacturing and development through its one‑stop bioconjugate CRDMO services. The agreement signals continued industry consolidation around proprietary linker‑payload platforms as firms seek to improve ADC therapeutic index and speed programs to clinic. Technical note: payload‑linker platforms control drug release and bystander effects in ADCs; having exclusive access to a validated linker can materially affect preclinical success and manufacturability.