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Illumina announced that our Board of Directors rejected Roche’s unsolicited tender offer to acquire us for $44.50 per share. This announcement was made after the Board thoroughly reviewed the offer and made a unanimous determination that Roche’s offer is grossly inadequate in multiple respects, dramatically undervalues Illumina and is not in the best interests of Illumina’s stockholders.

Simply put, the Board believes that Roche’s offer does not begin to reflect Illumina’s value as a standalone company.

Simply put, the Board believes that Roche’s offer does not begin to reflect Illumina’s value as a standalone company.

Our Board strongly believes that Illumina’s business plan as an independent entity will deliver value to our stockholders – and by extension, opportunity for all of us – that is far superior to Roche’s grossly inadequate offer.

The Board’s filed response, along with the related press release, can be found on Illumina’s website. We urge you to read them for more information.

You can expect business as usual at Illumina. We must remain fully focused on executing as we always have.

It has been, and will be continue to be, business as usual at Illumina. We must remain fully focused on executing as we always have.

We were legally constrained in our communications with you until the Board completed its formal review and filed its response. That response, along with the related press release, can be found on Illumina’s website. We urge you to read them for more information.

We were not and are not seeking a sale – the offer from Roche was unsolicited.

Our Board and management team are enthusiastic about our future opportunities and remain committed to executing our business strategy, and building near and long-term value for all of our stockholders.

We have a legal obligation as a public company to do what’s in the best interests of our stockholders but, at the same time, we recognize that our success as a company is very much based on the contributions made by our

employees. Our culture is based on trying to do the right thing by all of our constituents, including stockholders, customers, suppliers, partners, employees, and of course the researchers, healthcare providers and patients who depend on our products and services.

I can’t speculate. Our Board clearly has tremendous confidence in the value we are creating as an independent company.

Absolutely not. In fact, it’s quite the opposite: Illumina is growing and financially healthy, which is something Roche itself has recognized.

I can’t speculate. Our Board has recommended that stockholders not tender their shares, based on its conclusion that Roche’s offer is inadequate from a financial point of view and – given the significant potential of our Company – is not in the best interests of our stockholders.

We also have corporate defenses such as our stockholder rights plan – commonly known as a “poison pill” – that give our Board the tools it needs to protect value for our stockholders.

Roche has correctly observed that we have an outstanding workforce and we couldn’t agree with that more. But a merger of the companies is a purely hypothetical event. The bottom line is that Roche’s offer dramatically undervalues Illumina and we intend to vigorously resist Roche’s opportunistic attempt to acquire the Company.

It’s far too hypothetical to speculate.

It won’t. The best thing we can do now is to remain fully focused on executing as we always have.

Customers should know that we do not expect this situation to impact them. We remain fully committed to meeting – and exceeding – their needs and expectations.

(For customer-facing employees) You will receive some suggested talking points to guide your discussions with customers if they ask about this situation.

It’s business as usual at Illumina and we remain fully focused on executing as we always have.

Feel free to reach out to me at any time. In addition, please do not hesitate to contact Jay, Christian or Marc Stapley with any questions or concerns.

A tender offer is when a company or individual (in this case, Roche) makes an offer to purchase some or all of the shares in a corporation (in this case, Illumina). Tender offers may be solicited or unsolicited, but in this case, it was unsolicited.

The commencement of the tender offer means that investors are provided with information and a means to sell (or “tender”) their shares to Roche. Illumina’s Board has recommended that stockholders do not sell their shares to Roche.

A hostile offer is a commonly used term to describe a takeover attempt that was not invited by the other party (in this case, Illumina). Since we did not solicit this proposal, and the Board has not been actively trying to sell the Company, the media and others may refer to it as “hostile.”

Yes, but since the offer does not begin to reflect Illumina’s value as a standalone company, our Board does not believe that selling their shares would be in stockholders’ best interests.

Pursuant to their fiduciary duty, our Board has made a recommendation on Roche’s tender offer. In acting on such a deadline, it is important that you review the Board’s recommendation and all of the underlying reasons that informed that recommendation. You can find the Board’s complete response in the Company’s 14D-9 filing, which is available on our website.

Also referred to as a “poison pill”, this is a common measure that many companies undertake at various times for various reasons, and that Illumina has taken to ensure that our stockholders receive fair treatment and protection in connection with any proposal or offer to acquire the Company, including the proposal announced by Roche. The Rights Agreement will provide stockholders with adequate time to properly assess any such proposal or offer without undue pressure, while safeguarding their opportunity to realize the long-term value of their investment in the Company.

Generally, in a stockholder rights agreement, a company issues rights to existing stockholders to acquire a large number of new securities if any entity acquires a certain percentage of the company’s total stock. It provides stockholders (other than the bidder) with rights to buy more stock in the event of an attempted control acquisition.

The Board implemented the Rights Agreement to ensure that our stockholders receive fair treatment and protection in connection with any proposal or offer to acquire the Company, including the proposal announced by Roche. The Rights Agreement will provide stockholders with adequate time to properly assess any such proposal or offer without undue pressure, while safeguarding their opportunity to realize the long-term value of their investment in the Company.

No.

The announcement does not affect your unvested stock options/RSUs.

It’s far too hypothetical to begin speculating about that sort of thing.