Proprietary Information and Inventions Agreement

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[ILLUMINA LOGO]

                                                                   Exhibit 10.30

February 14, 2005

Scott Kahn

Re: Illumina, Inc.

Dear Scott;

It gives me great pleasure to set forth the principal terms for you to join

Illumina, Inc. (the "Company").

Position:           VP and Chief Information Officer

Responsibilities:   The Chief Information Officer is a position of strategic and

                    technical leadership having responsibility for all of the

                    scientific software and IT activities of the Company as well

                    as leadership of specific projects. Principal

                    responsibilities include:

                       -  Direct reporting responsibility for the

                          Bioinformatics, LIMS, software development and IT

                          functions.

                       -  Development of strategies to use information

                          technology as a competitive advantage

                       -  Economically scaling internal information systems to

                          match the growth in product volume and complexity

                       -  Unifying the software architecture of the Company's

                          internal systems and external products

                       -  Externally representing the company on issues related

                          to information systems

                       -  Interacting with customers as part of the sales

                          process