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Filed Pursuant to Rule 424(b)(3)
Registration No. 333-89630

August 9, 2002

PROSPECTUS

4,027,446 Shares

Finisar Corporation

Common Stock


        This Prospectus relates to the public offering, which is not being underwritten, of shares of the common stock of Finisar Corporation. The shares of our common stock will be offered by New Focus, Inc. which received its shares when we acquired certain assets of New Focus. We will receive no part of the proceeds of the sale of any shares offered in this prospectus. All expenses of registration incurred in connection with this offering are being borne by us, but all selling and other expenses incurred by the selling stockholder will be borne by the selling stockholder. None of the shares offered pursuant to this prospectus have been registered prior to the filing of the registration statement of which this prospectus is a part.

        The common stock offered in this prospectus may be offered and sold by the selling stockholder directly or through broker-dealers acting solely as agents. In addition, the broker-dealers may acquire the common stock as principals. The distribution of the common stock may be effected in one or more of the following types of transactions:

        These transactions may include block transactions or crosses. Crosses are transactions in which the same broker acts as an agent on both sides of the trade. These transactions may be made at market prices and on terms prevailing at the time of sale, prices related to such prevailing market prices or negotiated prices. Usual and customary or specially negotiated brokerage fees or commissions may be paid by the selling stockholder in connection with these sales.

        Finisar Corporation's common stock is traded on the Nasdaq National Market under the symbol "FNSR". On August 9, 2002, the last reported sales price for the common stock was $1.48 per share.

        INVESTING IN THE COMMON STOCK OFFERED IN THIS PROSPECTUS INVOLVES A HIGH DEGREE OF RISK. SEE "RISK FACTORS" BEGINNING ON PAGE 4.


        The selling stockholder and any broker executing selling orders on behalf of the selling stockholder may be deemed to be an "underwriter" within the meaning of the Securities Act of 1933. Commissions received by a broker executing selling orders may be deemed to be underwriting commissions under the Securities Act.


        NEITHER THE SECURITIES AND EXCHANGE COMMISSION NOR ANY STATE
SECURITIES COMMISSION HAS APPROVED OR DISAPPROVED THESE SECURTIES OR
PASSED UPON THE ACCURACY OR ADEQUACY OF THIS PROSPECTUS.
ANY REPRESENTATION TO THE CONTRARY IS A CRIMINAL OFFENSE.



TABLE OF CONTENTS

 
  Page
Disclosure Regarding Forward-Looking Statements   i
Summary   1
Risk Factors   4
Use of Proceeds   16
Dividend Policy   16
Description of Capital Stock   17
Selling Stockholder   20
Plan of Distribution   21
Legal Matters   22
Experts   22
Where You Can Find More Information   22

        You should rely only on the information contained or incorporated by reference in this prospectus. We have not authorized anyone to provide you with different information. If anyone provides you with different or inconsistent information, you should not rely on it. The selling stockholder is not making an offer to sell these securities in any jurisdiction where the offer or sale is not permitted. You should assume that the information appearing in this prospectus is accurate only as of the date on the front cover of this prospectus. Our business, financial condition, results of operations and prospects may have changed since that date.


        Finisar is a registered trademark of Finisar Corporation. This prospectus contains product names, trade names and trademarks of Finisar and other organizations.


        The terms "Finisar," "we," "us," "our," and the "company" refer only to Finisar Corporation and its consolidated subsidiaries.


DISCLOSURE REGARDING FORWARD-LOOKING STATEMENTS

        Some of the statements in this prospectus and in the documents incorporated by reference constitute forward-looking statements within the meaning of the Private Securities Litigation Reform Act of 1995. We use words like "anticipates", "believes", "plans", "expects", "future", "intends" and similar expressions to identify these forward-looking statements. We have based these forward-looking statements on our current expectations and projections about future events; however, business and operations are subject to a variety of risks and uncertainties, including those listed under "Risk Factors" and elsewhere in this prospectus, and, consequently, actual results may materially differ from those projected by any forward-looking statements. You should not place undue reliance on these forward-looking statements.

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SUMMARY

        This summary highlights selected information contained elsewhere in this prospectus. You should read the entire prospectus and the documents incorporated by reference in this prospectus carefully before making an investment decision.


Finisar Corporation

        We are a leading provider of fiber optic subsystems and network test and monitoring systems that enable high-speed data communications over local area networks, or LANs, storage area networks, or SANs, and metropolitan access networks, or MANs. We are focused on the application of digital fiber optics to provide a broad line of high-performance, reliable, value-added optical subsystems for data networking and storage equipment manufacturers. Our line of optical components and subsystems supports a wide range of network applications, transmission speeds, distances and physical mediums. We also provide network performance test and monitoring systems that assist networking and storage equipment manufacturers in the efficient design of reliable, high-speed networking systems and the testing and monitoring of the performance of these systems.

        To date, our revenues have been principally derived from sales to equipment manufacturers who sell products for building and testing storage area networks. Approximately 68% of our total revenues in fiscal 2001 and 66% of our total revenues in fiscal 2002 were derived from sales to these customers and the remaining portion of our sales were primarily to customers who sell Gigabit Ethernet applications for building and testing LAN and MAN networks. We sell our products to leading storage equipment manufacturers such as Brocade, EMC and Emulex as well as to leading data networking equipment manufacturers such as Cisco Systems, Extreme Networks and Foundry Networks.

        The development and manufacture of high quality, cost-effective fiber optic subsystems for LANs, SANs and MANs present a number of significant technical challenges. Data integrity, reliability and standards compliance become increasingly difficult at high transmission speeds. Additionally, manufacturers require optical subsystems that support a broad range of network applications. To date, we believe that only a limited number of companies have developed the specialized expertise required to engineer fiber optic subsystems and network performance test systems that meet the requirements of manufacturers of high-speed data networking and storage systems. Our optical subsystems and network test and monitoring systems are designed to provide the following key benefits to systems manufacturers:

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        Our goal is to be the optical subsystem and network performance test system provider of choice for multiple protocols and network applications. We intend to maintain our technological leadership through continual enhancement of our existing products and the development of new products as evolving technology permits higher speed transmission of data, with greater capacity, over longer distances. We also intend to acquire complementary technologies which enhance our product portfolio, reduce costs or improve customer service. We plan to leverage our relationships with our existing customers as they enter new, high-speed data communications markets and to expand our sales and marketing organization in order to establish new relationships with other key data and storage networking manufacturers. By capitalizing on our customers' satisfaction and our service-oriented approach, we intend to take advantage of cross-selling opportunities.

        Since October 2000, we have acquired Sensors Unlimited, Inc., Demeter Technologies, Inc., Medusa Technologies, Inc., Shomiti Systems, Inc. and Transwave Fiber, Inc. and certain assets, including equipment and intellectual property, of AIFOtec GmbH in Germany. These acquisitions have broadened our product offerings and provided us access to advanced optical component technologies that we believe will enable us to develop more integrated subsystems and will allow us to accelerate our product development cycle.

        We were incorporated in California in April 1987 and reincorporated in Delaware in November 1999. Our principal executive offices are located at 1308 Moffett Park Drive, Sunnyvale, California 94089, our telephone number is (408) 548-1000 and our website is located at www.finisar.com. Information on our website is not a part of this prospectus.


Recent Developments

Acquisition of Assets of New Focus, Inc.

        We entered into an agreement with New Focus, Inc., dated April 24, 2002 pursuant to which we acquired certain assets, including equipment, inventory and intellectual property related to the New Focus passives optical components business. Pursuant to the agreement, we agreed to issue shares of our common stock having an aggregate value of $6,750,000. The exact number of shares issued will be determined by dividing $6,750,000 by the ten-day average closing trading price for our common stock ending two days prior to the date of this prospectus. Based on the average closing trading price for our common stock for the ten trading days ending August 7, 2002, a total of 4,027,446 shares of common stock would be issued to New Focus.

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The Offering

Common stock offered by selling stockholder   4,027,446 shares

Common stock to be outstanding after this offering

 

201,139,086 shares

Use of proceeds

 

We will not receive any of the proceeds from the sale of shares by the selling stockholder.

Nasdaq National Market symbol

 

FNSR

        The number of shares that will be outstanding after the offering is based on the number of shares outstanding as of August 2, 2002 and excludes shares of common stock reserved for issuance under our stock option plans and employee stock purchase plan and upon exercise of stock options and warrants assumed in connection with our acquisitions of Sensors Unlimited, Inc., Demeter Technologies, Inc., Medusa Technologies, Inc., Shomiti Systems, Inc. and Transwave Fiber, Inc.

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RISK FACTORS

        An investment in the securities offered by this prospectus involves a high degree of risk. You should carefully consider the following factors and other information in this prospectus and in the documents incorporated by reference in this prospectus before deciding to purchase shares of our common stock. If any of these risks occur, our business could be harmed, the trading price of our stock could decline and you may lose all or part of your investment.


RISKS RELATED TO OUR BUSINESS

Our future revenues are inherently unpredictable, our operating results are likely to fluctuate from period to period, and if we fail to meet the expectations of securities analysts or investors, our stock price could decline significantly.

        Our quarterly and annual operating results have fluctuated in the past and are likely to fluctuate significantly in the future due to a variety of factors, some of which are outside of our control. Accordingly, we believe that period-to-period comparisons of our results of operations are not meaningful and should not be relied upon as indications of future performance. Some of the factors that could cause our quarterly or annual operating results to fluctuate include market acceptance of our products and the Gigabit Ethernet and Fibre Channel standards, market demand for the products manufactured by our customers, the introduction of new products and manufacturing processes, manufacturing yields, competitive pressures and customer retention.

        We may experience a delay in generating or recognizing revenues for a number of reasons. Orders at the beginning of each quarter typically do not equal expected revenues for that quarter and are generally cancelable at any time. Accordingly, we depend on obtaining orders during a quarter for shipment in that quarter to achieve our revenue objectives. Failure to ship these products by the end of a quarter may adversely affect our operating results. Furthermore, our customer agreements typically provide that the customer may delay scheduled delivery dates and cancel orders within specified time frames without significant penalty. Because we base our operating expenses on anticipated revenue trends and a high percentage of our expenses are fixed in the short term, any delay in generating or recognizing forecasted revenues could significantly harm our business. During the six months ended July 31, 2001, we experienced reduced orders, and in some cases cancellations of existing orders, from our customers due primarily to the general economic slowdown. As a result, our revenues declined on a sequential basis during the quarters ended April 30, 2001 and July 31, 2001 in comparison to the previous quarter. While revenues have increased during the subsequent three quarters, it is likely that in some future quarters our operating results may again decrease from the previous quarter or fall below the expectations of securities analysts and investors. In this event, the trading price of our common stock would significantly decline.

Failure to accurately forecast our revenues could result in additional charges for obsolete or excess inventories or non-cancelable purchase commitments.

        We base many of our operating decisions, and enter into purchase commitments, on the basis of anticipated revenue trends which are highly unpredictable. Some of our purchase commitments are not cancelable, and in some cases we are required to recognize a charge representing the amount of material or capital equipment purchased or ordered which exceed our actual requirements. We experienced a significant rate of growth between the quarters ended July 31, 2000 and January 31, 2001, when quarterly revenues increased from $27.2 million to $64.8 million. Based on projected revenue trends, we acquired inventories and entered into purchase commitments in order to meet anticipated increases in demand for our products. During the subsequent two quarters, revenue decreased to $52.2 million in the quarter ended April 30, 2001, and $34.2 million during the quarter

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ended July 31, 2001, as our customers reduced their demand for our products due to general economic conditions and excess inventories purchased in prior quarters. As a result, we recorded charges for obsolete and excess inventories and non-cancelable purchase commitments during the quarters ended April 30, 2001, and July 31, 2001, which contributed to substantial operating losses. Although revenues have increased during the three quarters ended April 30, 2002, revenue in future quarters could again fall substantially below our expectations, in which event we could be required to record additional charges for obsolete or excess inventories or non-cancelable purchase commitments.

Our operating costs may need to be reduced which could impact our future growth.

        We experienced a significant decline in revenues during the two quarters ended July 31, 2001 followed by three quarters of sequential growth in revenues along with an increase in operating losses due primarily to lower gross margins and continued increases in spending for research and development in anticipation of future revenue growth. While we continue to expect future revenue growth, we have taken steps to reduce our operating costs in order to conserve our cash and accelerate our return to profitability, and we may be required to take further action to reduce costs. These cost reduction measures may adversely affect our ability to market our products, introduce new and improved products and increase our revenues, which could adversely affect our business and cause the price of our stock to decline. In order to manage our growth effectively, we must reduce our product costs, complete our new product development programs and penetrate new customers. If we cannot manage growth effectively, our business could be significantly harmed.

Our success is dependent on the continued development of the emerging high-speed LAN, SAN and MAN markets.

        Our optical subsystem and network test and monitoring system products are used exclusively in high-speed local area networks, or LANs, storage area networks, or SANs, and metropolitan access networks, or MANs. Accordingly, widespread adoption of high-speed LANs, SANs and MANs is critical to our future success. The markets for high-speed LANs, SANs and MANs have only recently begun to develop and are rapidly evolving. Because these markets are new and evolving, it is difficult to predict their potential size or future growth rate. Potential end-user customers who have invested substantial resources in their existing data storage and management systems may be reluctant or slow to adopt a new approach, like high-speed LAN, SAN or MAN networks, particularly during periods of economic slowness. Our success in generating revenue in these emerging markets will depend, among other things, on the growth of these markets. There is significant uncertainty as to whether these markets ultimately will develop or, if they do develop, that they will develop rapidly. In particular, the general economic slowdown that began in 2001 has resulted in a slower than expected build out of LANs, SANs and MANs which, in turn, has resulted in reduced demand for the data networking and storage products of our customers, and consequently has hurt our sales. If the economic slowdown continues or worsens, or if the markets for high-speed LANs, SANs or MANs for any other reason fail to develop or develop more slowly than expected, or if our products do not achieve widespread market acceptance in these markets, our business would be significantly harmed.

We will face challenges to our business if our target markets adopt alternate standards to Fibre Channel and Gigabit Ethernet technology or if our products fail to comply with evolving industry standards and government regulations.

        We have based our product offerings principally on Fibre Channel and Gigabit Ethernet standards and our future success is substantially dependent on the continued market acceptance of these standards. If an alternative technology is adopted as an industry standard within our target markets, we would have to dedicate significant time and resources to redesign our products to meet this new industry standard. Our products comprise only a part of an entire networking system, and we depend

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on the companies that provide other components to support industry standards as they evolve. The failure of these companies, many of which are significantly larger than we are, to support these industry standards could negatively impact market acceptance of our products. Moreover, if we introduce a product before an industry standard has become widely accepted, we may incur significant expenses and losses due to lack of customer demand, unusable purchased components for these products and the diversion of our engineers from future product development efforts. In addition, because we may develop some products prior to the adoption of industry standards, we may develop products that do not comply with the eventual industry standard. Our failure to develop products that comply with industry standards would limit our ability to sell our products. Finally, if new standards evolve, we may not be able to successfully design and manufacture new products in a timely fashion, if at all, that meet these new standards.

        In the United States, our products must comply with various regulations and standards defined by the Federal Communications Commission and Underwriters Laboratories. Internationally, products that we develop also will be required to comply with standards established by local authorities in various countries. Failure to comply with existing or evolving standards established by regulatory authorities or to obtain timely domestic or foreign regulatory approvals or certificates could significantly harm our business.

We are dependent on widespread market acceptance of two product families, and our revenues will decline if the market does not continue to accept either of these product families.

        We currently derive substantially all of our revenue from sales of our optical components and subsystems and network test and monitoring systems. We expect that revenue from these products will continue to account for substantially all of our revenue for the foreseeable future. Accordingly, widespread acceptance of these products is critical to our future success. If the market does not continue to accept either our optical components and subsystems or our network test and monitoring systems, our revenues will decline significantly. Factors that may affect the market acceptance of our products include the continued growth of the markets for LANs, SANs, and MANs and, in particular, Gigabit Ethernet and Fibre Channel-based technologies as well as the performance, price and total cost of ownership of our products and the availability, functionality and price of competing products and technologies.

        Many of these factors are beyond our control. In addition, in order to achieve widespread market acceptance, we must differentiate ourselves from the competition through product offerings and brand name recognition. We cannot assure you that we will be successful in making this differentiation or achieving widespread acceptance of our products. Failure of our existing or future products to maintain and achieve widespread levels of market acceptance will significantly impair our revenue growth.

We depend on large purchases from a few significant customers, and any loss, cancellation, reduction or delay in purchases by these customers could harm our business.

        A small number of customers have accounted for a significant portion of our revenues. Our success will depend on our continued ability to develop and manage relationships with significant customers. Sales to our top three customers represented approximately 55% in fiscal 2000, 48% in fiscal 2001 and 31% in fiscal 2002. Although we are attempting to expand our customer base, we expect that significant customer concentration will continue for the foreseeable future.

        The markets in which we sell our products are dominated by a relatively small number of systems manufacturers, thereby limiting the number of our potential customers. Our dependence on large orders from a relatively small number of customers makes our relationship with each customer critically important to our business. We cannot assure you that we will be able to retain our largest customers, that we will be able to attract additional customers or that our customers will be successful in selling

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their products that incorporate our products. We have in the past experienced delays and reductions in orders from some of our major customers. We experienced reduced orders, and in some cases cancellations of existing orders, from our customers during the six month period ended July 31, 2001. In addition, our customers have in the past sought price concessions from us and will continue to do so in the future. Further, some of our customers may in the future shift their purchases of products from us to our competitors or to joint ventures between these customers and our competitors. The loss of one or more of our largest customers, any reduction or delay in sales to these customers, our inability to successfully develop relationships with additional customers or future price concessions that we may make could significantly harm our business.

Because we do not have long-term contracts with our customers, our customers may cease purchasing our products at any time if we fail to meet our customers' needs.

        Typically, we do not have long-term contracts with our customers. As a result, our agreements with our customers do not provide any assurance of future sales. Accordingly:

        Sales are typically made pursuant to individual purchase orders, often with extremely short lead times. If we are unable to fulfill these orders in a timely manner, we will lose sales and customers.

Our market is subject to rapid technological change, and to compete effectively we must continually introduce new products that achieve market acceptance.

        The markets for our products are characterized by rapid technological change, frequent new product introductions, changes in customer requirements and evolving industry standards. We expect that new technologies will emerge as competition and the need for higher and more cost effective bandwidth increases. Our future performance will depend on the successful development, introduction and market acceptance of new and enhanced products that address these changes as well as current and potential customer requirements. The introduction of new and enhanced products may cause our customers to defer or cancel orders for existing products. In addition, a slowdown in demand for existing products ahead of a new product introduction could result in a writedown in the value of inventory on hand related to existing products. We have in the past experienced a slowdown in demand for existing products and delays in new product development and such delays may occur in the future. To the extent customers defer or cancel orders for existing products due to a slowdown in demand or in the expectation of a new product release or there is any delay in development or introduction of our new products or enhancements of our products, our operating results would suffer. We also may not be able to develop the underlying core technologies necessary to create new products and enhancements, or to license these technologies from third parties. Product development delays may result from numerous factors, including:

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        The development of new, technologically advanced products is a complex and uncertain process requiring high levels of innovation and highly skilled engineering and development personnel, as well as the accurate anticipation of technological and market trends. We cannot assure you that we will be able to identify, develop, manufacture, market or support new or enhanced products successfully, if at all, or on a timely basis. Further, we cannot assure you that our new products will gain market acceptance or that we will be able to respond effectively to product announcements by competitors, technological changes or emerging industry standards. Any failure to respond to technological change would significantly harm our business.

Continued competition in our markets may lead to a reduction in our prices, revenues and market share.

        The markets for optical components and subsystems and network test and monitoring systems for use in LANs, SANs and MANs are highly competitive. Our current competitors include a number of domestic and international companies, many of which have substantially greater financial, technical, marketing and distribution resources and brand name recognition than we have. We expect that more companies, including some of our customers, will enter the market for optical subsystems and network test and monitoring systems. We may not be able to compete successfully against either current or future competitors. Increased competition could result in significant price erosion, reduced revenue, lower margins or loss of market share, any of which would significantly harm our business. For optical subsystems, we compete primarily with Agilent Technologies, Inc., Infineon Technologies AG, JDS Uniphase Corporation (which recently acquired the optical transceiver business of International Business Machines Corporation), Luminent, Inc., Molex Premise Networks, Optical Communications Products, Inc., Picolight Inc. and Stratos Lightwave, Inc. (formerly Methode Electronics). For network test and monitoring systems, we compete primarily with Ancot Corporation, I-Tech Corporation, Xyratex International and Network Associates, Inc. Our competitors continue to introduce improved products with lower prices, and we will have to do the same to remain competitive. In addition, some of our current and potential customers may attempt to integrate their operations by producing their own optical components and subsystems and network test and monitoring systems or acquiring one of our competitors, thereby eliminating the need to purchase our products. Furthermore, larger companies in other related industries, such as the telecommunications industry, may develop or acquire technologies and apply their significant resources, including their distribution channels and brand name recognition, to capture significant market share.

Decreases in average selling prices of our products may reduce gross margins.

        The market for optical subsystems is characterized by declining average selling prices resulting from factors such as increased competition, the introduction of new products and increased unit volumes as manufacturers continue to deploy network and storage systems. We have in the past experienced, and in the future may experience, substantial period-to-period fluctuations in operating results due to declining average selling prices. We anticipate that average selling prices will decrease in the future in response to product introductions by competitors or us, or by other factors, including price pressures from significant customers. Therefore, we must continue to develop and introduce on a timely basis new products that incorporate features that can be sold at higher average selling prices. Failure to do so could cause our revenues and gross margins to decline, which would significantly harm our business.

        We may be unable to reduce the cost of our products sufficiently to enable us to compete with others. Our cost reduction efforts may not allow us to keep pace with competitive pricing pressures or lead to improved gross margins. In order to remain competitive, we must continually reduce the cost of manufacturing our products through design and engineering changes. We may not be successful in redesigning our products or delivering our products to market in a timely manner. We cannot assure

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you that any redesign will result in sufficient cost reductions to allow us to reduce the price of our products to remain competitive or improve our gross margin.

Shifts in our product mix may result in declines in gross margins.

        Our gross profit margins vary among our product families, and our gross margins are generally higher on our network test and monitoring systems than on our optical subsystems. Our gross margins are generally lower for newly introduced products and improve as unit volumes increase. Our overall gross margins have fluctuated from period to period as a result of shifts in product mix, the introduction of new products, decreases in average selling prices for older products and our ability to reduce product costs.

We are subject to pending legal proceedings.

        A class action lawsuit was filed on November 30, 2001, in the United States District Court for the Southern District of New York on behalf of purchasers of our common stock alleging violations of federal securities laws. The case is brought purportedly on behalf of all persons who purchased our common stock from November 17, 1999 through December 6, 2000. The complaint names as defendants Finisar, Jerry S. Rawls, our President and Chief Executive Officer, Frank H. Levinson, our Chairman of the Board and Chief Technical Officer, Stephen K. Workman, our Vice President, Finance and Chief Financial Officer, and an investment banking firm that served as an underwriter for our initial public offering in November 1999 and a secondary offering in April 2000. In April 2002, an amended complaint was served on the defendants. The amended complaint alleges violations of Sections 11, 12(a)(2) and 15 of the Securities Act of 1933 and Section 10(b) of the Securities Exchange Act of 1934, on the grounds that the prospectuses incorporated in the registration statements for the offerings failed to disclose, among other things, that (i) the underwriter had solicited and received excessive and undisclosed commissions from certain investors in exchange for which the underwriter allocated to those investors material portions of the shares of our stock sold in the offerings, and (ii) the underwriter had entered into agreements with customers whereby the underwriter agreed to allocate shares of our common stock sold in the offerings to those customers in exchange for which the customers agreed to purchase additional shares of our stock in the aftermarket at pre-determined prices. No specific damages are claimed. We are aware that similar allegations have been made in lawsuits relating to more than 300 other initial public offerings conducted in 1999 and 2000. Those cases have been consolidated for pretrial purposes. The issuer defendants, including Finisar, have filed a motion to dismiss the complaints. A hearing date on the motion has not been set. We believe that the allegations against us and our officers and directors are without merit and intend to contest them vigorously. However, the litigation is in a preliminary stage and we cannot predict its outcome. The litigation process is inherently uncertain. If the outcome of the litigation is adverse to us and if we are required to pay significant monetary damages, our business would be significantly harmed.

Our customers often evaluate our products for long and variable periods, which causes the timing of our revenues and results of operations to be unpredictable.

        The period of time between our initial contact with a customer and the receipt of an actual purchase order may span a year or more. During this time, customers may perform, or require us to perform, extensive and lengthy evaluation and testing of our products before purchasing and using them in their equipment. Our customers do not typically share information on the duration or magnitude of these qualification procedures. The length of these qualification processes also may vary substantially by product and customer, and, thus, cause our results of operations to be unpredictable. While our potential customers are qualifying our products and before they place an order with us, we may incur substantial sales and marketing expenses and expend significant management effort. Even after incurring such costs we ultimately may not sell any products to such potential customers. In

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addition, these qualification processes often make it difficult to obtain new customers, as customers are reluctant to expend the resources necessary to qualify a new supplier if they have one or more existing qualified sources. Once our products have been qualified, our agreements with our customers have no minimum purchase commitments. Failure of our customers to incorporate our products into their systems would significantly harm our business.

If we cannot successfully transfer our manufacturing processes to our new facility in Malaysia and improve our manufacturing yields, our costs of operations will be harmed.

        We have recently shifted a substantial portion of our manufacturing requirements to our new facility in Malaysia. The transfer of these manufacturing processes represents a significant fixed cost. In addition, it is difficult to control the manufacturing processes in a facility located outside of the United States. As a result, we have experienced difficulty in implementing our manufacturing processes in this new facility, which have resulted in low manufacturing yields and increased our cost of revenues. Sustained manufacturing yield problems or disruptions in product flow could limit our revenue, adversely affect our competitive position and reputation and result in additional cost or cancellation of orders under agreements with our customers.

We depend on facilities located outside of the United States to manufacture a substantial portion of our products, which subjects us to additional risks.

        In addition to our facility in Malaysia, we rely on three contract manufacturers located outside of the United States. Each of these facilities and manufacturers subjects us to the following additional risks associated with international manufacturing:

        Any of these factors could significantly impair our ability to source our contract manufacturing requirements internationally.

Our business and future operating results are subject to a wide range of uncertainties arising out of the recent terrorist attacks.

        Like other U.S. companies, our business and operating results are subject to uncertainties arising out of the recent terrorist attacks on the United States, including the potential worsening or extension of the current global economic slowdown, the economic consequences of military action or additional terrorist activities and associated political instability, and the impact of heightened security concerns on domestic and international travel and commerce. In particular, due to these uncertainties we are subject to:

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We may lose sales if our suppliers fail to meet our needs.

        We currently purchase several key components used in the manufacture of our products from single or limited sources. We depend on these sources to meet our needs. Moreover, we depend on the quality of the products supplied to us over which we have limited control. We have encountered shortages and delays in obtaining components in the past and expect to encounter shortages and delays in the future. If we cannot supply products due to a lack of components, or are unable to redesign products with other components in a timely manner, our business will be significantly harmed. We have no long-term or short-term contracts for any of our components. As a result, a supplier can discontinue supplying components to us without penalty. If a supplier discontinued supplying a component, our business may be harmed by the resulting product manufacturing and delivery delays.

        We use rolling forecasts based on anticipated product orders to determine our component requirements. Lead times for materials and components that we order vary significantly and depend on factors such as specific supplier requirements, contract terms and current market demand for particular components. If we overestimate our component requirements, we may have excess inventory, which would increase our costs. If we underestimate our component requirements, we may have inadequate inventory, which could interrupt our manufacturing and delay delivery of our products to our customers. Any of these occurrences would significantly harm our business.

Prior and future acquisitions could be difficult to integrate, disrupt our business, dilute stockholder value and harm our operating results.

        Since October 2000, we have completed the acquisition of five privately-owned companies and certain assets from two other companies. We expect to continue to review opportunities to acquire other businesses, products or technologies that would complement our current products, expand the breadth of our markets or enhance our technical capabilities, or that may otherwise offer growth opportunities. In five of our seven acquisitions, we issued stock as all or a portion of the consideration, and we are obligated to release additional shares from escrow and to issue additional shares in connection with two of the acquisitions upon the occurrence of certain contingencies and the achievement of certain milestones. The issuance of stock in these and any future transactions has or would dilute stockholders' percentage ownership.

        Other risks associated with acquiring the operations of other companies include:

        We cannot assure you that we would be successful in overcoming problems encountered in connection with such acquisitions, and our inability to do so could significantly harm our business. In addition, to the extent that the economic benefits associated with such acquisitions diminish in the future, we may be required to record writedowns of goodwill, intangible assets or other assets associated with such acquisitions.

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We have made and may continue to make strategic investments which may not be successful and may result in the loss of all or part of our invested capital.

        We have made minority equity investments in early-stage technology companies, totaling $41.7 million, including a loan of $7.0 million to one company in which we also have a minority equity position, and we intend to review additional opportunities to make strategic equity investments in pre-public companies where we believe such investments will provide us with opportunities to gain access to important technologies or otherwise enhance important commercial relationships. We have little or no influence over the early-stage companies in which we have made or may make these strategic, minority equity investments. Each of these investments in pre-public companies involves a high degree of risk. We may not be successful in achieving the financial, technological or commercial advantage upon which any given investment is premised, and failure by the early-stage company to achieve its own business objectives or to raise capital needed on acceptable economic terms could result in a loss of all or part of our invested capital.

We have substantially increased our indebtedness and may have insufficient cash flow to meet our debt service obligations.

        As a result of the sale of our 51/4 convertible subordinated notes in October 2001, we have incurred $125 million of additional indebtedness, substantially increasing our ratio of debt to total capitalization. We may incur substantial additional indebtedness in the future. The level of our indebtedness, among other things, could:

        We will be required to generate cash sufficient to pay our indebtedness and other liabilities, including all amounts due on the notes, and to conduct our business operations. We may not be able to cover our anticipated debt service obligations. This may materially hinder our ability to make payments on the notes. Our ability to meet our future debt service obligations will depend upon our future performance, which will be subject to financial, business and other factors affecting our operations, many of which are beyond our control. If we fail to make payments on the notes when due, the holders of the notes could declare a default and demand immediate payment of the entire principal amount of the notes, which would significantly harm our business.

We may not be able to obtain additional capital in the future.

        We believe that our existing balance of cash, cash equivalents and short-term investments, together with the cash expected to be generated from our future operations, will be sufficient to meet our cash needs for working capital and capital expenditures for at least the next 12 months. We may however require additional financing to fund our operations in the future. The significant contraction in the capital markets, particularly in the technology sector, may make it difficult for us to raise additional capital if and when it is required, especially if we experience disappointing operating results. If adequate capital is not available to us as required, or is not available on favorable terms, our business, financial condition and results of operations will be adversely affected.

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Because of intense competition for technical personnel, we may not be able to recruit or retain necessary personnel.

        We believe our future success will depend in large part upon our ability to attract and retain highly skilled managerial, technical, sales and marketing, finance and manufacturing personnel. In particular, we will need to increase the number of technical staff members with experience in high-speed networking applications as we further develop our product lines. Competition for these highly skilled employees in our industry is intense. Our failure to attract and retain these qualified employees could significantly harm our business. The loss of the services of any of our qualified employees, the inability to attract or retain qualified personnel in the future or delays in hiring required personnel could hinder the development and introduction of and negatively impact our ability to sell our products. In addition, employees may leave our company and subsequently compete against us. Moreover, companies in our industry whose employees accept positions with competitors frequently claim that their competitors have engaged in unfair hiring practices. We have been subject to claims of this type and may be subject to such claims in the future as we seek to hire qualified personnel. Some of these claims may result in material litigation. We could incur substantial costs in defending ourselves against these claims, regardless of their merits.

Our products may contain defects that may cause us to incur significant costs, divert our attention from product development efforts and result in a loss of customers.

        Networking products frequently contain undetected software or hardware defects when first introduced or as new versions are released. Our products are complex and defects may be found from time to time. In addition, our products are often embedded in or deployed in conjunction with our customers' products which incorporate a variety of components produced by third parties. As a result, when problems occur, it may be difficult to identify the source of the problem. These problems may cause us to incur significant damages or warranty and repair costs, divert the attention of our engineering personnel from our product development efforts and cause significant customer relation problems or loss of customers, all of which would harm our business.

Our failure to protect our intellectual property may significantly harm our business.

        Our success and ability to compete is dependent in part on our proprietary technology. We rely on a combination of patent, copyright, trademark and trade secret laws, as well as confidentiality agreements and licensing arrangements, to establish and protect our proprietary rights. We license certain of our proprietary technology, including our digital diagnostics technology, to customers who include current and potential competitors, and we rely largely on provisions of our licensing agreements to protect our intellectual property rights in this technology. To date, we have relied primarily on proprietary processes and know-how to protect our intellectual property. Although we have filed applications for a number of patents, some of which have issued, we cannot assure you that any patents will issue as a result of pending patent applications or that our issued patents will be upheld. Any infringement of our proprietary rights could result in significant litigation costs, and any failure to adequately protect our proprietary rights could result in our competitors offering similar products, potentially resulting in loss of a competitive advantage and decreased revenues. Despite our efforts to protect our proprietary rights, existing patent, copyright, trademark and trade secret laws afford only limited protection. In addition, the laws of some foreign countries do not protect our proprietary rights to the same extent as do the laws of the United States. Attempts may be made to copy or reverse engineer aspects of our products or to obtain and use information that we regard as proprietary. Accordingly, we may not be able to prevent misappropriation of our technology or deter others from developing similar technology. Furthermore, policing the unauthorized use of our products is difficult. Litigation may be necessary in the future to enforce our intellectual property rights or to determine the

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validity and scope of the proprietary rights of others. This litigation could result in substantial costs and diversion of resources and could significantly harm our business.

Claims that we infringe third-party intellectual property rights could result in significant expenses or restrictions on our ability to sell our products.

        The networking industry is characterized by the existence of a large number of patents and frequent litigation based on allegations of patent infringement. We were recently involved in a series of related patent infringement lawsuits. From time to time, other parties may assert patent, copyright, trademark and other intellectual property rights to technologies and in various jurisdictions that are important to our business. Any claims asserting that our products infringe or may infringe proprietary rights of third parties, if determined adversely to us, could significantly harm our business. Any claims, with or without merit, could be time-consuming, result in costly litigation, divert the efforts of our technical and management personnel, cause product shipment delays or require us to enter into royalty or licensing agreements, any of which could significantly harm our business. Royalty or licensing agreements, if required, may not be available on terms acceptable to us, if at all. In addition, our agreements with our customers typically require us to indemnify our customers from any expense or liability resulting from claimed infringement of third party intellectual property rights. In the event a claim against us was successful and we could not obtain a license to the relevant technology on acceptable terms or license a substitute technology or redesign our products to avoid infringement, our business would be significantly harmed.

If we are unable to expand our direct sales operation and reseller distribution channels or successfully manage our expanded sales organization, our ability to increase our revenues will be harmed.

        Historically, we have relied primarily on a limited direct sales organization, supported by third party manufacturers' representatives, to sell our products domestically and on indirect distribution channels to sell our products internationally. Our distribution strategy focuses primarily on developing and expanding our direct sales organization in North America and our indirect distribution channels internationally. We may not be able to successfully expand our direct sales organization and the cost of any expansion may exceed the revenue generated. To the extent that we are successful in expanding our direct sales organization, we cannot assure you that we will be able to compete successfully against the significantly larger and well-funded sales and marketing operations of many of our current or potential competitors. In addition, if we fail to develop relationships with significant international resellers or domestic manufacturers' representatives, or if these resellers or representatives are not successful in their sales or marketing efforts, sales of our products may decrease and our business would be significantly harmed. We have granted exclusive rights to substantially all of our resellers to sell our products and to our representatives to market our products in their specified territories. Our resellers and representatives may not market our products effectively or continue to devote the resources necessary to provide us with effective sales, marketing and technical support. Our inability to effectively manage the expansion of our domestic sales and support staff or maintain existing or establish new relationships with domestic manufacturer representatives and international resellers would harm our business.

Our executive officers and directors and entities affiliated with them own a large percentage of our voting stock, which could have the effect of delaying or preventing a change in our control.

        As of June 28, 2002, our executive officers, directors and entities affiliated with them beneficially owned approximately 63.1 million shares or approximately 32% of the outstanding shares of our common stock. These stockholders, acting together, may be able to effectively control matters requiring approval by stockholders, including the election or removal of directors and the approval of mergers or other business combination transactions. This concentration of ownership could have the effect of

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delaying or preventing a change in our control or otherwise discouraging a potential acquirer from attempting to obtain control of us, which in turn could have an adverse effect on the market price of our common stock or prevent our stockholders from realizing a premium over the market price for their shares of common stock.

Delaware law and our charter documents contain provisions that could discourage or prevent a potential takeover, even if such a transaction would be beneficial to our stockholders.

        Some provisions of our Certificate of Incorporation and Bylaws, as well as provisions of Delaware law, may discourage, delay or prevent a merger or acquisition that a stockholder may consider favorable. These provisions include:

Our headquarters and a portion of our manufacturing operations are located in California where natural disasters may occur.

        Currently, our corporate headquarters and a portion of our manufacturing operations are located in California. California historically has been vulnerable to natural disasters and other risks, such as earthquakes, fires and floods, which at times have disrupted the local economy and posed physical risks to our property. We presently do not have redundant, multiple site capacity in the event of a natural disaster. In the event of such disaster, our business would suffer.

Our stock price has been and may continue to be volatile.

        The trading price of our common stock has been and may continue to be subject to large fluctuations, which may result in losses to investors. Our stock price may increase or decrease in response to a number of events and factors, including:

        Part of this volatility is attributable to the current state of the stock market, in which wide price swings are common. This volatility may adversely affect the prices of our common stock regardless of our operating performance.

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USE OF PROCEEDS

        We will not receive any proceeds from the sale by the selling stockholder of the common stock offered hereby.


DIVIDEND POLICY

        We have never paid cash dividends on our common stock. We currently intend to retain earnings for use in our business and do not anticipate paying any cash dividend in the foreseeable future. Any future declaration and payment of dividends will be subject to the discretion of our board of directors, will be subject to applicable law and will depend on our results of operations, earnings, financial condition, contractual limitations, cash requirements, future prospects and other factors deemed relevant by our Board of Directors.

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DESCRIPTION OF CAPITAL STOCK

        Our authorized capital stock consists of 500,000,000 shares of common stock, $0.001 par value per share, and 5,000,000 shares of preferred stock, $0.001 par value per share.

        The following is a summary of the material terms of our common stock and preferred stock. Please see our certificate of incorporation for more detailed information.

Common Stock

        The holders of our common stock are entitled to one vote for each share held of record on all matters submitted to a vote of stockholders. Holders of a majority of the shares of common stock entitled to vote in any election of directors may elect all of the directors standing for election. Subject to preferences applicable to any outstanding preferred stock, holders of common stock are entitled to receive ratably any dividends declared by the Board of Directors out of funds legally available therefor. See "Dividend Policy." In the event of a liquidation, dissolution or winding up of Finisar, holders of common stock are entitled to share ratably in the assets remaining after payment of liabilities and the liquidation preferences of any outstanding preferred stock. Holders of our common stock have no preemptive, conversion or redemption rights. Each outstanding share of common stock is, and all shares of common stock issued upon conversion of the notes will be, fully paid and non-assessable.

Preferred Stock

        Up to 5,000,000 shares of undesignated preferred stock are authorized for issuance. Our Board of Directors has the authority, without further action by our stockholders, to issue preferred stock in one or more series. In addition, the Board of Directors may fix the rights, preferences and privileges of any preferred stock it determines to issue. Any or all of these rights may be superior to the rights of the common stock. Preferred stock could thus be issued quickly with terms calculated to delay or prevent a change in control of Finisar or to make removal of management more difficult. Additionally, the issuance of preferred stock may decrease the market price of our common stock. At present, we have no plans to issue any shares of preferred stock.

Registration Rights

        Pursuant to a registration rights agreement dated as of October 15, 2001 between us and the initial purchasers of our 51/4% Convertible Subordinated Notes, we filed, at our expense, with the Commission a shelf registration statement on Form S-3 covering resales by holders of all notes and the common stock issuable upon conversion of the notes. The registration statement became effective on January 18, 2002. We have summarized portions of the registration rights agreement below. We are required to use our best efforts to keep the registration statement effective until the earlier of (A) the date that is two years after the last date of original issuance of any of the notes or (October 15, 2003); (B) the date when the holders of the notes and the common stock issuable upon conversion of the notes are able to sell all such securities immediately without restriction pursuant to the volume limitation provisions of Rule 144 under the Securities Act or any successor rule thereto or otherwise; or (C) the sale pursuant to the shelf registration statement of all securities registered thereunder.

        We will be permitted to suspend the use of the prospectus that is part of the shelf registration statement under certain circumstances relating to pending corporate developments, public filings with

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the Commission and similar events for a period not to exceed 30 days in any three-month period and not to exceed an aggregate of 90 days in any 12-month period. If:

each, a registration default, additional interest as liquidated damages will accrue on the notes, from and including the day following the registration default to but excluding the day on which the registration default has been cured. Liquidated damages will be paid semi-annually in arrears, with the first semi-annual payment due on the first interest payment date, as applicable, following the date on which such liquidated damages begin to accrue, and will accrue at a rate per year equal to:

        In no event will liquidated damages accrue at a rate per year exceeding 0.5%. If a holder has converted some or all of its notes into common stock, the holder will be entitled to receive equivalent amounts based on the principal amount of the notes converted.

        Under our agreement with New Focus, we agreed to file, at our expense, with the Commission a shelf registration statement on Form S-3 covering the resale of the common stock issued to New Focus. Other terms of our agreement with respect to the registration of the shares issued to New Focus are set forth under the caption "Plan of Distribution" below.

Antitakeover Provisions

        Finisar is subject to Section 203 of the Delaware General Corporation Law regulating corporate takeovers, which prohibits a Delaware corporation from engaging in any business combination with an "interested stockholder," unless:

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        Except as otherwise specified in Section 203, an "interested stockholder" is defined to include (a) any person that is the owner of 15% or more of the outstanding voting securities of the corporation, or is an affiliate or associate of the corporation and was the owner of 15% or more of the outstanding voting stock of the corporation at any time within three years immediately prior to the date of determination and (b) the affiliates and associates of any such person.

        Provisions of our certificate of incorporation and bylaws may have the effect of making it more difficult for a third party to acquire, or of discouraging a third party from attempting to acquire, control of Finisar. These provisions could cause the price of our common stock to decrease. Some of these provisions allow us to issue preferred stock without any vote or further action by the stockholders, eliminate the right of stockholders to act by written consent without a meeting and eliminate cumulative voting in the election of directors. These provisions may make it more difficult for stockholders to take specific corporate actions and could have the effect of delaying or preventing a change in control of Finisar.

        Our certificate of incorporation provides that the Board of Directors will be divided into three classes of directors, with each class serving a staggered three-year term. The classification system of electing directors may discourage a third party from making a tender offer or otherwise attempting to obtain control of us and may maintain the incumbency of the Board of Directors, because the classification of the Board of Directors generally increases the difficulty of replacing a majority of the directors.

Transfer Agent and Registrar

        The transfer agent and registrar for our common stock is American Stock Transfer and Trust Company.

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SELLING STOCKHOLDER

        The shares of common stock offered hereby were originally issued by us in a private placement in connection with the acquisition of assets from New Focus, Inc. The selling stockholder, which term includes New Focus and any of its pledgees, donees or their successors, may from time to time offer and sell pursuant to this prospectus any or all of the common stock offered hereby.

        The following table sets forth information as of August 9, 2002, with respect to the selling stockholder and the common stock beneficially owned by the selling stockholder that may be offered pursuant to this prospectus. Such information has been obtained from the selling stockholder. The selling stockholder does not have, and within the past three years has not had, any position, office or other material relationship with us or any of our predecessors or affiliates other than as a result of the ownership of the shares of common stock acquired in connection with the sale of assets to us, as described under the caption "Summary—Recent Developments" above. Because the selling stockholder may offer all, some or none of the common stock pursuant to this prospectus, no estimate can be given as to the amount of the common stock that will be held by the selling stockholder upon completion of this offering.

 
  Number of Shares of
Common Stock

Selling Stockholder

  Beneficially
Owned(1)

  Offered Hereby
  Owned After
the Offering

New Focus, Inc.   4,027,446   4,027,446   0

(1)
This registration statement shall also cover any additional shares of Finisar common stock which become issuable in connection with the shares registered for sale hereby by reason of any stock dividend, stock split, recapitalization or other similar transaction effected without the receipt of consideration which results in an increase in the number of outstanding shares of Finisar common stock.

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PLAN OF DISTRIBUTION

        We will not receive any of the proceeds of the sale of the common stock offered by this prospectus. The common stock may be sold from time to time to purchasers:

        The selling stockholder and any such broker-dealers or agents who participate in the distribution of the common stock may be deemed to be "underwriters." As a result, any profits on the sale of the common stock by the selling stockholder and any discounts, commissions or concessions received by any such broker-dealers or agents might be deemed to be underwriting discounts and commissions under the Securities Act. If the selling stockholder was to be deemed an underwriter, the selling stockholder may be subject to certain statutory liabilities of, including, but not limited to, Sections 11, 12 and 17 of the Securities Act and Rule 10b-5 under the Exchange Act. If the common stock is sold through underwriters or broker-dealers, the selling stockholder will be responsible for underwriting discounts or commissions or agent's commissions.

        The common stock may be sold in one or more transactions at:

        These sales may be effected in transactions:

        These transactions may include block transactions or crosses. Crosses are transactions in which the same broker acts as an agent on both sides of the trade.

        To our knowledge, there are currently no plans, arrangements or understandings between the selling stockholder and any underwriter, broker-dealer or agent regarding the sale of the common stock by the selling stockholder. The selling stockholder might not sell any or all of the common stock offered pursuant to this prospectus. The selling stockholder might instead transfer, devise or gift the common stock by other means not described in this prospectus. In addition, any shares of common stock covered by this prospectus that qualify for sale pursuant to Rule 144 of the Securities Act may be sold under Rule 144 rather than pursuant to this prospectus.

        The selling stockholder and any other person participating in such distribution will be subject to the Exchange Act. The Exchange Act rules include, without limitation, Regulation M, which may limit the timing of purchases and sales of any of the common stock by the selling stockholder and any other such person. In addition, Regulation M under the Exchange Act may restrict the ability of any person engaged in the distribution of the common stock to engage in market-making activities with respect to the underlying common stock being distributed for a period of up to five business days prior to the commencement of such distribution. This may affect the marketability of the common stock and the ability of any person or entity to engage in market-making activities with respect to the common stock.

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        We agreed with the selling stockholder to keep the registration statement of which this prospectus constitutes a part effective until the earlier of:

        We intend to de-register any of the shares not sold by the selling stockholder at the end of such period. At such time, however, any unsold shares may be freely tradable subject to compliance with Rule 144 under the Securities Act.

        We have agreed to pay substantially all of the expenses incidental to the registration, offering and sale of the common stock to the public other than commissions, fees and discounts of underwriters, brokers, dealers and agents.


LEGAL MATTERS

        The validity of the shares of common stock offered hereby will be passed upon for us by Gray Cary Ware & Freidenrich LLP, Palo Alto, California. As of August 8, 2002, attorneys of Gray Cary Ware & Freidenrich LLP beneficially own an aggregate of 21,900 shares of our common stock.


EXPERTS

        Ernst & Young LLP, independent auditors, have audited the consolidated financial statements and schedule of Finisar Corporation at April 30, 2002 and 2001 and for the fiscal years ended April 30, 2002, 2001 and 2000, as set forth in their reports which are incorporated by reference in this prospectus and elsewhere in the registration statement. Our consolidated financial statements and schedule are incorporated by reference in reliance on Ernst & Young LLP's reports, given on their authority as experts in accounting and auditing.

        The financial statements of Sensors Unlimited, Inc. incorporated by reference in this registration statement have been audited by Arthur Andersen LLP, independent public accountants, as indicated in their report with respect thereto, and are incorporated by reference in reliance upon the authority of said firm as experts in accounting and auditing. Arthur Andersen LLP has not consented to the inclusion of their report in this prospectus, and we have dispensed with the requirement to file their consent in reliance of Rule 437a promulgated under the Securities Act. Because Arthur Andersen LLP has not consented to the inclusion of their report in this prospectus, you will not be able to recover against Arthur Andersen LLP under Section 11 of the Securities Act for any untrue statements of a material fact contained in the financial statements audited by Arthur Andersen LLP or any omissions to state a material fact required to be stated therein.

        Ernst & Young LLP, independent auditors, have audited the financial statements of Demeter Technologies, Inc. at October 31, 2000 and for the period from inception (June 22, 2000) to October 31, 2000, as set forth in their report which is incorporated by reference in this prospectus and elsewhere in the registration statement. Demeter Technologies, Inc.'s financial statements are incorporated by reference in reliance on Ernst & Young LLP's report, given on their authority as experts in accounting and auditing.


WHERE YOU CAN FIND MORE INFORMATION

        We file reports, proxy statements and other information with the SEC. You may read and copy all or any portion of any materials we file with the SEC at the SEC's public reference room at Room

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1024, Judiciary Plaza, 450 Fifth Street, N.W., Washington, D.C. 20549 and at the regional offices of the SEC. You can request copies of these documents upon payment of a duplicating fee, by writing to the SEC. Please call the SEC at 1-800-SEC-0330 for further information on the operation of the public reference rooms. Our SEC filings will also be available to you on the SEC's Web site at http://www.sec.gov. Our SEC filings are also available at the offices of the Nasdaq National Market, 1730 K Street, N.W., Washington, D.C. 20006-1500.

        The information incorporated by reference is considered to be a part of this prospectus, and information that we file later with the Commission will automatically update and supersede this information. We incorporate by reference the documents listed below and any future filings made by us with the Commission under Sections 13(a), 13(c), 14 or 15(d) of the Exchange Act until this offering is complete:

        Any statement contained in a document that is incorporated by reference will be modified or superseded for all purposes to the extent that a statement contained in this prospectus (or in any other document that is subsequently filed with the Commission and incorporated by reference) modifies or is contrary to that previous statement. Any statement so modified or superseded will not be deemed a part of this prospectus except as so modified or superseded.

        You may request a copy of these filings, at no cost, by writing or telephoning us at the following address: Investor Relations, Finisar Corporation, 1308 Moffett Park Drive, Sunnyvale, California 94089, (408) 548-1000.

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QuickLinks

TABLE OF CONTENTS
DISCLOSURE REGARDING FORWARD-LOOKING STATEMENTS
SUMMARY
Finisar Corporation
Recent Developments
The Offering
RISK FACTORS
RISKS RELATED TO OUR BUSINESS
USE OF PROCEEDS
DIVIDEND POLICY
DESCRIPTION OF CAPITAL STOCK
SELLING STOCKHOLDER
PLAN OF DISTRIBUTION
LEGAL MATTERS
EXPERTS
WHERE YOU CAN FIND MORE INFORMATION