Krisan Biotech Co Ltd

Krisan Biotech Co., Ltd. (also referred to as KriSan Biotech or KSB) is a privately held global Contract Development and Manufacturing Organization (CDMO) founded in August 2015. Headquartered in Tainan City, Taiwan, the company employs approximately 50-60 personnel. One estimate places its annual revenue at $3.5 million, with an estimated valuation of $11.2 million based on industry averages.

KriSan Biotech specializes in the process development and GMP production of complex drug substances. Its core offerings include services for antibody-drug conjugates (ADC), peptide-drug conjugates (PDC), XDC, complex small molecules, peptides, and oligonucleotides, including lipid nanoparticle (LNP) formulations. The company provides comprehensive "one-stop" services, covering the entire spectrum from preclinical development to cGMP manufacturing and commercialization, and holds PIC/S GMP certification. It has delivered over 170 new chemical entity products to partners globally.

As an operating company, KriSan Biotech's patent litigation posture is defensive, with one tracked case as a defendant and zero as a plaintiff. This indicates they are typically a target in patent challenges rather than an assertive entity. The company is involved in a proceeding before the Patent Trial and Appeal Board (PTAB) of the United States Patent and Trademark Office (USPTO).

The single notable tracked case is Unified Patents v. Atossa Therapeutics Inc et al., where KriSan Biotech is listed as a defendant. This PTAB case challenged the patentability of U.S. Patent No. 11,572,334, which covers "Sustained Release Compositions of Endoxifen." In January 2025, the PTAB issued a final written decision finding all claims of this patent unpatentable, a decision that Atossa Therapeutics chose not to appeal. Unified Patents is known for petitioning the PTAB to challenge patents it deems unpatentable or invalid, acting as a deterrence entity against the assertion of poor-quality patents.