EXHIBIT 4.6 ----------- COMMON SECURITY CERTIFICATE THIS COMMON SECURITY HAS NOT BEEN REGISTERED UNDER THE SECURITIES ACT OF 1933, AS AMENDED (THE "SECURITIES ACT"), OR ANY STATE SECURITIES LAWS OR ANY OTHER APPLICABLE SECURITIES LAW. NEITHER THIS COMMON SECURITY NOR ANY INTEREST OR PARTICIPATION HEREIN MAY BE REOFFERED, SOLD, ASSIGNED, TRANSFERRED, PLEDGED, ENCUMBERED OR OTHERWISE DISPOSED OF IN THE ABSENCE OF SUCH REGISTRATION OR UNLESS SUCH TRANSACTION IS EXEMPT FROM, OR NOT SUBJECT TO, REGISTRATION. THE HOLDER OF THIS COMMON SECURITY BY ITS ACCEPTANCE HEREOF AGREES TO OFFER, SELL OR OTHERWISE TRANSFER THIS COMMON SECURITY, PRIOR TO THE DATE (THE "RESALE RESTRICTION TERMINATION DATE") WHICH IS TWO YEARS AFTER THE LATER OF THE ORIGINAL ISSUANCE DATE HEREOF AND THE LAST DATE ON WHICH GREATER BAY BANCORP (THE "CORPORATION") OR ANY "AFFILIATE" OF THE CORPORATION WAS THE OWNER OF THIS COMMON SECURITY (OR ANY PREDECESSOR OF THIS COMMON SECURITY) ONLY (A) TO THE CORPORATION, (B) PURSUANT TO A REGISTRATION STATEMENT WHICH HAS BEEN DECLARED EFFECTIVE UNDER THE SECURITIES ACT, (C) SO LONG AS THIS COMMON SECURITY IS ELIGIBLE FOR RESALE PURSUANT TO RULE 144A UNDER THE SECURITIES ACT ("RULE 144A"), TO A PERSON IT REASONABLY BELIEVES IS A "QUALIFIED INSTITUTIONAL BUYER" (AS DEFINED IN RULE 144A) THAT PURCHASES FOR ITS OWN ACCOUNT OR FOR THE ACCOUNT OF A QUALIFIED INSTITUTIONAL BUYER TO WHOM NOTICE IS GIVEN THAT THE TRANSFER IS BEING MADE IN RELIANCE ON RULE 144A, (D) TO AN INSTITUTIONAL "ACCREDITED INVESTOR" WITHIN THE MEANING OF SUBPARAGRAPH (A)(1), (2), (3) OR (7) OF RULE 501 UNDER THE SECURITIES ACT THAT IS ACQUIRING THIS COMMON SECURITY FOR ITS OWN ACCOUNT, OR FOR THE ACCOUNT OF SUCH AN INSTITUTIONAL ACCREDITED INVESTOR, FOR INVESTMENT PURPOSES AND NOT WITH A VIEW TO, OR FOR OFFER OR SALE IN CONNECTION WITH, ANY DISTRIBUTION IN VIOLATION OF THE SECURITIES ACT, OR (E) PURSUANT TO ANY OTHER AVAILABLE EXEMPTION FROM THE REGISTRATION REQUIREMENTS UNDER THE SECURITIES ACT, SUBJECT TO THE RIGHT OF GBB CAPITAL II (THE "TRUST") AND THE CORPORATION PRIOR TO ANY SUCH OFFER, SALE OR TRANSFER (i) PURSUANT TO CLAUSE (D) OR (E) TO REQUIRE THE DELIVERY OF AN OPINION OF COUNSEL, CERTIFICATIONS AND/OR OTHER INFORMATION SATISFACTORY TO EACH OF THEM, AND (ii) PURSUANT TO CLAUSE (D) TO REQUIRE THAT TRANSFEROR DELIVER TO THE TRUST A LETTER FROM THE TRANSFEREE SUBSTANTIALLY IN THE FORM OF ANNEX A TO THE OFFERING MEMORANDUM DATED AUGUST 7, 1998. SUCH HOLDER FURTHER AGREES THAT IT WILL DELIVER TO EACH PERSON TO WHOM THIS COMMON SECURITY IS TRANSFERRED A NOTICE SUBSTANTIALLY TO THE EFFECT OF THIS LEGEND. Certificate Evidencing Common Securities of GBB CAPITAL II Floating Rate Common Securities (liquidation amount $1,000 per Common Security) GBB CAPITAL II, a statutory business trust created under the laws of the State of Delaware (the "Trust"), hereby certifies that Greater Bay Bancorp (the "Holder") is the registered owner of 928 common securities of the Trust representing undivided beneficial interests in the assets of the Trust designated the Floating Rate Common Securities (liquidation amount $1,000 per Common Security) (the "Common Securities"). Subject to the terms of the Trust Agreement (as defined below), the Common Securities are transferable on the books and records of the Trust, in person or by a duly authorized attorney, upon surrender of this Certificate duly endorsed and in proper form for transfer. The designation, rights, privileges, restrictions, preferences and other terms and provisions of the Common Securities represented hereby are issued and shall in all respects be subject to the provisions of the Amended and Restated Trust Agreement of the Trust dated as of August 12, 1998, as the same may be amended from time to time (the "Trust Agreement"), including the designation of the terms of the Common Securities as set forth in Annex I to the Trust Agreement. Capitalized terms used but not defined herein shall have the meaning given them in the Trust Agreement. The Sponsor will provide a copy of the Trust Agreement, the Common Securities Guarantee and the Indenture (including any supplemental indenture) to a Holder without charge upon written request to the Trust at its principal place of business. Upon receipt of this Certificate, the Holder is bound by the Trust Agreement and is entitled to the benefits thereunder and to the benefits of the Common Securities Guarantee to the extent provided therein. By acceptance hereof, the Holder agrees to treat, for United States federal income tax purposes, the Debentures as indebtedness and the Common Securities as evidence of indirect beneficial ownership in the Debentures. IN WITNESS WHEREOF, the Trust has executed this certificate this 12th day of August, 1998. GBB CAPITAL II By: /s/ Steven C. Smith ---------------------------------- Steven C. Smith Administrative Trustee 2 Distributions on each Common Security will be payable at a rate per annum, reset quarterly, equal to 3-month LIBOR (as defined in the Trust Agreement) plus 150 basis points (the "Coupon Rate"), such rate being the rate of interest payable on the Debentures to be held by the Property Trustee. Distributions in arrears for more than one quarterly period will bear interest thereon compounded quarterly at the Coupon Rate (to the extent permitted by applicable law). Pursuant to the Registration Rights Agreement, in certain limited circumstances the Debenture Issuer will be required to pay Liquidated Damages (as defined in the Registration Rights Agreement) with respect to the Debentures. The term "Distributions", as used herein, includes such cash distributions and any and all such interest and Liquidated Damages, if any, payable unless otherwise stated. A Distribution is payable only to the extent that payments are made in respect of the Debentures held by the Property Trustee and to the extent the Property Trustee has funds legally available therefor. Distributions on the Common Securities will be cumulative, will accrue from the most recent date to which Distributions have been paid or, if no Distributions have been paid, from August 12, 1998 and will be payable quarterly in arrears, on March 15, June 15, September 15 and December 15, of each year, commencing December 15, 1998, except as otherwise described below. Distributions will be computed on the basis of the actual number of days elapsed in such period and a 360-day year. As long as no Event of Default has occurred and is continuing under the Indenture, the Debenture Issuer has the right under the Indenture to defer payments of interest by extending the interest payment period at any time and from time to time on the Debentures for a period not exceeding 20 consecutive calendar quarterly periods, including the first such quarterly period during such extension period (each an "Extension Period"), provided that -------- ---- no Extension Period shall end on a date other than an Interest Payment Date for the Debentures or extend beyond the Maturity Date of the Debentures. As a consequence of such deferral, Distributions will also be deferred. Notwithstanding such deferral, quarterly Distributions will continue to accumulate with interest thereon (to the extent permitted by applicable law, but not at a rate exceeding the rate of interest then accruing on the Debentures) at the applicable periodic Coupon Rate compounded quarterly during any such Extension Period. Prior to the termination of any Extension Period, the Debenture Issuer may further defer payments of interest by further extending such Extension Period; provided that such Extension Period, together with all -------- ---- such previous and further extensions within such Extension Period, may not (i) exceed 20 consecutive quarterly periods, including the first quarterly period during such Extension Period, (ii) end on a date other than an Interest Payment Date for the Debentures or (iii) extend beyond the Maturity Date of the Debentures. Payments of accrued Distributions will be payable to Holders as they appear on the books and records of the Trust on the record date immediately preceding the end of the Extension Period. Upon the termination of any Extension Period and the payment of all amounts then due, the Debenture Issuer may commence a new Extension Period, subject to the above requirements. Subject to the receipt by the Sponsor of any and all required regulatory approvals and to certain other conditions set forth in the Trust Agreement and the Indenture, the Property Trustee may, at the direction of the Sponsor, at any time dissolve the Trust and cause the Debentures to be distributed to the Holders of the Securities in liquidation of the Trust or, simultaneously with any redemption of the Debentures, cause a Like Amount of the Securities to be redeemed by the Trust. 3 The Common Securities shall be redeemable as provided in the Trust Agreement. Under certain circumstances, the rights of the holders of the Common Securities shall be subordinate to the rights of the holders of the Capital Securities, as provided in the Trust Agreement. 4