Arrowhead Research Subsidiary, Nanotechnica, Inc., Obtains Exclusive Rights to Over 80 New Patents and Patent Applications From Caltech.

PASADENA, Calif. -- Arrowhead Research Corporation (Nasdaq:ARWR) (Nasdaq:ARWRW) announced today that the California Institute of Technology ("Caltech") has granted exclusive rights to over 80 new U.S. and international patents and patent applications covering microfluidics and micromachines technology to Nanotechnica, Inc., a subsidiary of Arrowhead Research. R. Bruce Stewart, President of Arrowhead Research, remarked, "This new technology further strengthens the growing portfolio of patent rights held by Arrowhead and its subsidiaries, which includes exclusive rights to over 180 U.S. and international patents and patent applications in the nanotechnology space."

Dr. Yu-Chong Tai, the primary inventor of the licensed technology, is a consultant to Nanotechnica. Dr. Tai has extensive experience in micromachines and microfluidics and has developed devices such as sensors, anemometers, actuators, microvalves, and micromotors. He is a Caltech Professor of Electrical Engineering and the Director of the Caltech Micromachining Laboratory.

The Nanotechnica research and development team is presently led by Chief Technical Officer Dr. Michael Roukes, who is currently on leave from Caltech. Dr. Roukes, Caltech Professor of Physics, Applied Physics and Bioengineering, is the Director of Caltech's Kavli Nanoscience Institute, co-founder of the Nanosystems Biology Alliance, co-founder and co-director of both the Initiative in Computational Molecular Biology and the Laboratory for Large Scale Integration of Nanostructures, and chair of the external advisory board of Harvard University's nanoscience center. Nanotechnica's R&D group also includes consultant Dr. Scott Fraser, the Anna L. Rosen Professor of Biology and Director of the Biological Imaging Center at Caltech.

"We are pleased to have Dr. Tai as a key scientific consultant to Nanotechnica. The combination of Dr. Roukes' expertise in nano-electro-mechanical systems, Dr. Tai's experience with microfluidics, and Dr. Fraser's knowledge of biological systems will provide Nanotechnica with one of the most talented interdisciplinary nanotech teams in the world," said Stewart.

Nanotechnica is initially focusing on commercializing nanoscale devices such as scanning probe tips, pathogen sensors, and medical diagnostics. Nanotechnica seeks to establish capabilities for mass production of a variety of different, proprietary nanoscale devices and systems.

About Arrowhead Research Corporation

Arrowhead Research is a nanotechnology company structured to bring together a diverse and innovative mix of technologies, rights to a broad suite of intellectual property, and some of the most respected minds in this dynamic field. There are three strategic components to Arrowhead's business model:

--Forming or acquiring majority-owned subsidiaries engaged in the development and commercialization of nanoscale materials, devices, and systems.

--Funding of nanoscience research at universities in exchange for the exclusive right to commercialize resulting intellectual property.

--Acquisition, license and sublicense of intellectual property in the field of nanotechnology.

Arrowhead Research operates three majority-owned subsidiary companies:

--Aonex Technologies, Inc., developing and commercializing proprietary semiconductor nanomaterial technology.

--Insert Therapeutics, Inc., which is developing and commercializing a proprietary nanoscale drug delivery system.

--Nanotechnica, Inc., formed to develop capabilities for mass-production of a variety of different, proprietary nanoscale devices and systems.

Arrowhead is funding three research efforts in nanotechnology at the California Institute of Technology in the areas of nanomaterials, nanoelectronics, and nanobiomolecular tools.

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