1 FILED PURSUANT TO RULE 424(b)(3) REGISTRATION NO. 333-36708 PROSPECTUS SUPPLEMENT $150,000,000 PROTEIN DESIGN LABS, INC. 5.50% CONVERTIBLE SUBORDINATED NOTES DUE FEBRUARY 15, 2007 993,337 SHARES OF COMMON STOCK ISSUABLE ON CONVERSION OF THE NOTES - -------------------------------------------------------------------------------- This prospectus supplement ("Prospectus Supplement") supplements the Prospectus dated June 7, 2000 (the "Prospectus") of Protein Design Labs, Inc., a Delaware corporation (the "Company") and relates to the Company's 5.50% Convertible Subordinated Notes due February 15, 2007, held by certain security holders who may offer for sale the notes and shares of the Company's common stock into which the notes are convertible at any time, at market prices prevailing at the time of sale or at privately negotiated prices. The selling security holders may sell the notes or the common stock directly to purchasers or through underwriters, broker-dealers or agents, that may receive compensation in the form of discounts, concessions or commissions. The Company will not receive any proceeds from this offering. This Prospectus Supplement should be read in conjunction with the Prospectus and this Prospectus Supplement is qualified by reference to the Prospectus, except to the extent that the information herein contained supersedes the information contained in the Prospectus. Capitalized terms used in this Prospectus Supplement and not otherwise defined herein have the meanings specified in the Prospectus. The date of this Prospectus Supplement is September 15, 2000.
2 SELLING SECURITY HOLDERS The Selling Security Holders table is hereby amended (as amended, the "Amended Table") to reflect changes in the selling security holders and in the selling security holders' principal amounts of notes. The Amended Table sets forth, as of the date of this Prospectus Supplement, information with respect to the selling security holders and the respective principal amounts of notes beneficially owned by each selling security holder that may be offered pursuant to this prospectus. Such information has been obtained from the selling security holders. None of the selling security holders has, or within the past three years has had, any position, office or other material relationship with us or any of our predecessors or affiliates. Because the selling security holders may offer all or some portion of the notes or the common stock issuable upon conversion of the notes pursuant to this prospectus, no estimate can be given as to the amount of the notes or the common stock issuable upon conversion of the notes that will be held by the selling security holders upon termination of any such sales. In addition, the selling security holders identified below may have sold, transferred or otherwise disposed of all or a portion of their notes since the date on which they provided the information regarding their notes in transactions exempt from the registration requirements of the Securities Act. Principal Amount Number of Shares of of Notes Common Stock ---------------- ------------------------------------------- Beneficially Owned and Offered Beneficially Offered Owned After Selling Security Holder (1) Hereby (1) Owned(1)(2) Hereby the Offering - ------------------------------------------------ ---------------- ----------- --------- ------------- Allstate Insurance Company $ 500,000 11,911 3,311 8,600 Aloha Airlines Non-Pilots Pension Trust $ 75,000 496 496 -- Aloha Airlines Pilots Retirement Trust $ 45,000 298 298 -- Alta Partners Holdings, LDC $ 2,500,000 16,556 16,556 -- Argent Classic Convertible Arbitrage Fund $ 7,000,000 46,357 46,357 -- (Bermuda) L.P. Associated Electric & Gas Insurance Services $ 370,000 2,450 2,450 -- Limited Baird, Patrick & Co., Inc. $ 2,520,000 16,688 16,688 -- BNP Arbitrage SNC $10,000,000 66,225 66,225 -- BNP Cooper Neff Convertible Strategies Fund, L.P. $ 688,000 4,556 4,556 -- C&H Sugar Company, Inc. $ 120,000 794 794 -- CALAMOS Market Neutral Fund - CALAMOS Investment $ 600,000 3,973 3,973 -- Trust CIBC World Markets $17,293,000 114,523 114,523 -- Coastal Convertibles Ltd. $ 400,000 2,649 2,649 -- Consulting Group Capital Markets Funds $ 200,000 1,324 1,324 -- Deephaven Domestic Convertible Trading Ltd. $ 6,500,000 43,046 43,046 -- Deutsche Bank Securities, Inc. $29,670,000 196,490 196,490 -- Fidelity Financial Trust: Fidelity Convertible $ 3,640,000 24,105 24,105 -- Securities Fund First Republic Bank $ 100,000 662 662 -- Grace Brothers, Ltd. $ 2,000,000 13,245 13,245 -- Hawaiian Airlines Employees Pension Plan-IAM $ 65,000 430 430 -- Hawaiian Airlines Pension Plan for Salaried $ 15,000 99 99 -- Employees Hawaiian Airlines Pilots Retirement Plan $ 100,000 662 662 -- Helix Convertible Opportunities Fund Ltd. $ 1,445,000 9,569 9,569 -- Helix Convertible Opportunities, L.P. $ 2,560,000 16,953 16,953 -- Highbridge International LLC $11,000,000 72,847 72,847 -- Janus Capital Corporation $ 2,067,000 13,688 13,688 -- Jefferies & Co. $ 210,000 1,390 1,390 -- KBC Financial Products USA $ 6,000,000 39,735 39,735 -- Kentfield Trading, Ltd. $ 4,667,000 30,907 30,907 -- Lincoln National Convertible Securities Fund $ 3,000,000 19,867 19,867 --
3 Principal Amount Number of Shares of of Notes Common Stock ---------------- ------------------------------------------- Beneficially Owned and Offered Beneficially Offered Owned After Selling Security Holder (1) Hereby (1) Owned(1)(2) Hereby the Offering - ------------------------------------------------ ---------------- ----------- --------- ------------- Lord Abbett Bond Debenture Fund $ 3,000,000 19,867 19,867 -- Museum of Fine Arts, Boston $ 26,000 172 172 -- New Hampshire Retirement System $ 155,000 1,026 1,026 -- Onyx Capital Management $ 5,090,000 33,708 33,708 -- Parker-Hannifin Corporation $ 45,000 298 298 -- ProMutual $ 96,000 635 635 -- Putnam Asset Allocation Funds - Balanced Portfolio $ 170,000 1,125 1,125 -- Putnam Asset Allocation Funds - Conservative $ 112,000 741 741 -- Portfolio Putnam Balanced Retirement Fund $ 52,000 344 344 -- Putnam Convertible Income - Growth Trust $ 455,000 3,013 3,013 -- Putnam Convertible Opportunities and Income Trust $ 69,000 456 456 -- Queen's Health Plan $ 25,000 165 165 -- Rhone-Poulenc Rorer Pension Plan $ 33,000 218 218 -- R2 Investments, LDC $ 21,000,000 139,072 139,072 -- State of Oregon/SAIF Corporation $ 3,550,000 23,509 23,509 -- The Common Fund FAO Absolute Returns Fund $ 495,000 3,278 3,278 -- Tucker Anthony Inc. $ 42,000 278 278 -- University of Rochester $ 25,000 165 165 -- UBS Warburg LLC $ 140,000 927 927 -- ZCM / HFR Index Management, L.L.C. $ 70,000 463 463 -- Total: $150,000,000 1,001,955 993,355 8,600 =========== ======= ====== ===== (1) Information concerning the selling security holders may change from time to time and any such changed information will be set forth in supplements to this prospectus if and when necessary. In addition, the per share conversion price, and therefore the number of shares issuable upon conversion of the notes, is subject to adjustment under certain circumstances. Accordingly, the aggregate principal amount of notes and the number of shares of common stock issuable upon conversion of the notes offered hereby may increase or decrease. (2) Assumes a conversion price of $151.00 per share, and a cash payment in lieu of any fractional share interest.