Schedule 13D Stock Exchange Agreement

EXHIBIT 15 TO SCHEDULE 13D STOCK EXCHANGE AGREEMENT (SERIES I)

This STOCK EXCHANGE AGREEMENT (this "Agreement") is made and entered into as of April 2, 2004, between EXABYTE CORPORATION, a Delaware corporation (the "Company") and each of the owners of Series I preferred stock ("Series I") of the Company, named on Schedule 1 attached hereto and incorporated herein by reference, who have executed this Agreement (each a "Preferred Holder" and collectively, the "Preferred Holders"). Background

A. The Preferred Holders wish to exchange their Series I shares for shares of a newly designated series of preferred stock of the Company to be sold in the Private Placement (as defined below), referred to as the "New Series." The Company currently contemplates that the New Series will be called Series AA preferred stock of the Company. However, this Agreement applies to the New Series whatever the final title of such New Series is.

B. The Company has commenced steps for making and consummating a private placement of the New Series of preferred stock for a total purchase price of up to $20 million and with C.E. Unterberg, Towbin acting as the Company's exclusive financial advisor (the "Private Placement"). The parties acknowledge that this information is currently confidential. 1. Exchange of Shares 1.1 Exchange

Subject to the terms and conditions hereof, at the Closing (defined below) each Preferred Holder agrees to exchange the number of Series I shares set forth opposite such Preferred Holder's name on Schedule 1 (the "Tendered Shares"), including any and all related rights, for that number of shares of the New Series (the "Exchange Shares") that is convertible into the same number of shares of Common Stock as the Tendered Shares, assuming for such purpose the accrual of all dividends on the Tendered Shares through December 31, 2004, and the Company agrees to issue the Exchange Shares to such Preferred Holder (the "Exchange"). In connection with the Exchange, the Preferred Holders will receive any warrants or other consideration received by the purchasers of the New Series in the Private Placement on an equal per-share basis. The parties acknowledge and agree that the final terms and conditions of the New Series shall be as set forth in the Certificate of Designation of preferences and terms concerning the New Series prepared and filed with the Delaware Secretary of State in connection with the Private Placement. 1.2 Surrender and Issuance

At or before the Exchange, the Preferred Holders shall surrender, at the offices of the Company as directed, any and all certificates for the Tendered Shares. At the Closing, the Company will issue to each Preferred Holder certificates representing the Exchange Shares issuable to such holder in the Exchange and bearing an appropriate legend referring to the fact that the Exchange Shares were exchanged in reliance upon exemptions from registration provided by the Securities Act of 1933, as amended (the "Securities Act") and rules and regulations promulgated under the Securities Act. 2. CLOSING

The closing of the Exchange (the "Closing") shall take place at the offices of the Company and shall be held (a) concurrently with the consummation of the Private Placement, or (b) if requested by the Company, as soon as practicable (but not more than one business day) after the consummation of the Private Placement. (The date on which the Closing occurs is referred to as the "Closing Date.") 3. CLOSING CONDITIONS

3.1 The Company's obligation to complete the Exchange shall be subject to the following conditions, any one or more of which may be waived by the Company:

(a) consummation of the Private Placement in an amount not less than $15,000,000;

(b) the accuracy in all material respects of the representations and warranties made by Preferred Holders and the fulfillment in all material respects of those covenants of any Preferred Holders to be fulfilled on or before the Closing;

(c) concurrent consummation of the Exchange with all Preferred Holders; and

(d) no action or other legal proceeding pending or threatened against the Company relating to the shares being exchanged or the Exchange contemplated by this Agreement.

3.2 Each Preferred Holder's obligations to complete the Exchange shall be subject to the following conditions, any one or more of which may be waived by such Preferred Holder with respect to such Preferred Holder's obligations:

(a) consummation of the Private Placement in an amount not less than $15,000,000; and

(b) the accuracy in all material respects of the representations and warranties made by the Company and the fulfillment in all material respects of those covenants of the Company to be fulfilled on or before the Closing;

(c) concurrent consummation of the Exchange by the Company with all other Preferred Holders; and

(d) no action or other legal proceeding pending or threatened against such Preferred Holder relating to the shares being exchanged or the Exchange contemplated by this Agreement.

4. REPRESENTATIONS, WARRANTIES AND COVENANTS OF THE COMPANY

The Company hereby represents, warrants and covenants to each Preferred Holders as follows at the date hereof and also, except as may be disclosed otherwise in a letter delivered by the Company to such Preferred Holder prior to the Closing, as of the Closing Date: 4.1 Organization and Issuance of the Exchange Shares

(a) The Company has been duly incorporated and is validly existing as a corporation in good standing under the laws of the State of Delaware.

(b) The Exchange Shares have been duly authorized for issuance and sale to such Preferred Holder pursuant to this Agreement and, when issued and delivered by the Company pursuant to this Agreement against delivery of the Tendered Shares as set forth in this Agreement, will be validly issued and fully paid and nonassessable and free and clear of all restrictions, rights of third parties, pledges, liens and encumbrances, except any such restrictions as imposed by securities laws or as set forth in the terms and conditions of the New Series. The certificates evidencing the Exchange Shares will be in due and proper form under Delaware law.

(c) The issuance of the Exchange Shares is not subject to preemptive or other similar rights.

(d) Subject to the accuracy of the Preferred Holders' representations and warranties in this Agreement, the offer, Exchange, and issuance of the Exchange Shares in conformity with the terms of this Agreement constitute transactions exempt from the registration requirements of Section 5 of the Securities Act and from the registration or qualification requirements of the laws of any applicable state or United States jurisdiction. 4.2 Due Execution, Delivery and Performance

(a) This Agreement has been duly executed and deli ...