EXHIBIT 5

February 25, 2011

Equinix, Inc.

One Lagoon Drive, Fourth Floor

Redwood City, CA 94065

Ladies and Gentlemen:

I refer to your registration on Form S-8 (the “Registration Statement”) under the Securities Act of 1933, as amended, of 500,000 shares of Common Stock issuable in the aggregate under the 2004 Employee Stock Purchase Plan (the “Plan”). I advise you that, in my opinion, when such shares have been issued and sold pursuant to the applicable provisions of the Plan, and in accordance with the Registration Statement, such shares will be validly issued, fully paid and nonassessable shares of the Company’s Common Stock.

I hereby consent to the filing of this opinion as an exhibit to the Registration Statement.