EXHIBIT 4.8

THIS WARRANT AND THE SECURITIES REPRESENTED BY THIS WARRANT HAVE NOT BEEN REGISTERED UNDER THE SECURITIES ACT OF 1933 OR THE SECURITIES ACT OF ANY STATE AND MAY NOT BE SOLD OR TRANSFERRED UNLESS THERE IS AN
EFFECTIVE REGISTRATION STATEMENT UNDER SUCH ACTS COVERING THIS WARRANT AND THE SECURITIES REPRESENTED BY THIS WARRANT OR PURSUANT TO AN EXEMPTION FROM THE REGISTRATION AND PROSPECTUS DELIVERY REQUIREMENTS OF SUCH ACTS.

BIOLARGO, INC.

FORM OF WARRANT TO
PURCHASE COMMON STOCK



|                 |  |                   
|---------------- |  | ------------------
|WARRANT NO. XXXX |  | ISSUED: XXXX, 2007

THIS CERTIFIES THAT, for value received, __XXXXXXX__(the Holder), is entitled
to subscribe for and purchase from BIOLARGO, INC., a corporation organized under the laws of the state of Delaware (the Company), subject to Section 1(b) hereof, commencing at the time periods prescribed herein and ending at
5:00 p.m. California time on June 30, 2010, XXXX shares (the Shares) of common stock, par value, $0.00067, of the Company (the Common Stock). The exercise price for each Share subject to this Warrant
(the Warrant Price) is equal to $1.30. The number of Shares and the Warrant Price are subject to adjustment from time to time as provided in Section 4 of this Warrant.

This Warrant is issued in connection with and as consideration for the Convertible Note dated the date hereof and issued by the Company in favor of the
Holder, which Convertible Note has been issued pursuant the Holders investment in the Company.

1. Method of Exercise; Payment;
Issuance of New Warrant. (a) The purchase right represented by this Warrant may be exercised by the Holder, in whole or in part, subject to the limitation set forth below, and from time to time, by (i) the surrender of this Warrant
(with a notice of exercise in the form attached hereto as Exhibit A, duly executed) at the principal office of the Company and (ii) the payment to the Company, by check or wire transfer of funds to an account specified in writing by
the Company, of an amount equal to the aggregate Warrant Price. The Shares so purchased, representing the aggregate number of shares specified in the executed Exhibit A, shall be delivered to the Holder within a reasonable time, not exceeding
ten (10) business days, after this Warrant shall have been so exercised. Upon receipt by the Company of this Warrant at the office of the Company, in proper form for exercise and accompanied by the amount equal to the aggregate Warrant Price,
the Holder shall be deemed to be the holder of record of the Shares issuable upon such exercise, notwithstanding that the stock transfer books of the Company shall then be closed or that certificates representing such Shares shall not then be
actually delivered to the Holder.

(b) Notwithstanding anything else herein to the contrary, the Holder shall not have the
right, and the Company shall not have the obligation, to exercise all or any portion of this Warrant, unless and until each of the following events has first occurred: (i) the Companys stockholders have approved an increase in the number
of shares of common stock authorized by the Companys Certificate of Incorporation in an amount not less than the amount required to permit all warrants issued in this series to be converted into shares of the Companys Common Stock as
provided herein, at a validly held meeting of stockholders at which a quorum is present and acting throughout; and (ii) the Company has filed with the Secretary of State of State of Delaware a Certificate of Amendment to the Companys
Certificate of Incorporation to amend its Certificate of Incorporation to increase the number of shares of common stock authorized by the Companys Certificate of Incorporation.

(c) If this Warrant shall have been exercised only in part, the Company shall, at the time of delivery of such Shares, deliver to the
Holder a new Warrant evidencing the right to purchase the remaining Shares called



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for by this Warrant, which new Warrant shall in all other respects be identical with this Warrant, or, at the request of Holder, appropriate notation may be
made on this Warrant which shall then be returned to Holder.

2. Stock Fully Paid; Reservation of Shares. All Shares that may be
issued upon the exercise of the rights represented by this Warrant will, upon issuance, be fully paid and nonassessable, and free from all preemptive rights, taxes, liens and charges with respect to the issue thereof; provided, however, that the
Company shall not be required to pay any transfer taxes with respect to the issue of shares in any name other than that of the registered holder hereof. During the period within which the rights represented by this Warrant may be exercised, the
Company will at all times have authorized, and reserved for the purpose of the issue upon exercise of the purchase rights evidenced by this Warrant, a sufficient number of shares of Common Stock to provide for the exercise of the rights represented
by this Warrant. The Company shall at all times take all such action and obtain all such permits or orders as may be necessary to enable the Company lawfully to issue such Common Stock as duly and validly issued, fully paid and nonassessable shares
upon exercise in full of this Warrant.

3. Fractional Shares. No fractional shares of Common Stock will be issued in connection with
any exercise hereunder, but in lieu of such fractional shares the Company shall make a cash payment therefor upon the basis of the Fair Market Value of such Shares.

4. Adjustment. This Warrant shall be subject to adjustment from time to time upon the occurrence of certain events, as follows:

(a) Adjustment for Stock Splits and Combinations. If the Company shall at any time or from time to time after the date hereof
effect a subdivision of the outstanding Common Stock, the Warrant Price then in effect immediately before that subdivision shall be proportionately decreased. If the Company shall at any time or from time to time after the date hereof combine the
outstanding Common Stock, the Warrant Price then in effect immediately before the combination shall be proportionately increased. Any adjustment under this subsection shall become effective at the close of business on the date the subdivision or
combination becomes effective.

(b) Adjustment for Certain Dividends and Distributions. In the event the Company at
any time or from time to time after the date hereof shall make or issue a dividend or other distribution payable in additional shares of Common Stock, then and in each such event the Warrant Price shall be decreased as of the time of such issuance,
by multiplying the Warrant Price by a fraction:



| | (x) | the numerator of which shall be the total number of shares of Common Stock issued and outstanding immediately prior to the time of such issuance; and
| | --- | -----------------------------------------------------------------------------------------------------------------------------------------------------



| | (y) | the denominator of which shall be the total number of shares of Common Stock issued and outstanding immediately prior to the time of such issuance plus the number of shares of
Common Stock issuable in payment of such dividend or distribution.
| | --- | --------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------

(c) Adjustment of Number of Shares.
Upon each adjustment of the Warrant Price pursuant to either Section 4(a) or 4(b) of this Warrant, the number of shares of Common Stock purchasable upon exercise of this Warrant shall be adjusted to the number of shares of Common
Stock, calculated to the nearest one hundredth of a share, obtained by multiplying the number of shares of Common Stock purchasable immediately prior to such adjustment upon the exercise of the Warrant by the Warrant Price in effect prior to such
adjustment and dividing the product so obtained by the new Warrant Price.

(d) Adjustment for Reclassification, Exchange
and Substitution. If the Common Stock issuable upon the exercise of this Warrant are changed into the same or different number of shares of any class or classes of stock, whether by recapitalization, reclassification or otherwise (other than a
subdivision or combination provided for in Section 4(a) above, a dividend or distribution provided for in Section 4(b) above, or a reorganization, merger, consolidation or sale of assets, provided for in
Section 4(e) below), then and in any such event the Holder shall have the right thereafter to exercise this Warrant into the kind and amount of



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stock and other securities receivable upon such recapitalization, reclassification or other change, by holders of the number of shares of Common Stock for
which this Warrant might have been exercised immediately prior to such recapitalization, reclassification or change.

(e)
Reorganization, Mergers, Consolidations or Sales of Assets. If at any time or from time to time there is a capital reorganization of the Common Stock (other than a subdivision or combination provided for in Section 4(a) above, a
dividend or distribution provided for in Section 4(b) above, or a reclassification or exchange of shares provided for in Section 4(d) above) or a merger or consolidation of the Company with or into another entity, or a sale
of all or substantially all of the Companys properties and assets to any other person or entity, then, as a part of such reorganization, merger, consolidation or sale, provision shall be made so that the Holder shall thereafter be entitled to
receive upon exercise of this Warrant the number of shares of stock or other securities, money or property of the Company, or of the successor entity resulting from such merger or consolidation or sale, to which a holder of Common Stock deliverable
upon conversion would have been entitled on such capital reorganization, merger, consolidation, or sale. The Company shall not effect any reorganization, merger, consolidation or sale unless prior to the consummation thereof each entity or person
(other than the Company) that may be required to deliver any cash, securities or other property upon the exercise of this Warrant shall assume, by written instrument delivered to the Holder, the obligation to deliver to the Holder such cash,
securities or other property as in accordance with the foregoing provisions the Holder may be entitled to receive. The foregoing provisions of this Section 4(e)shall similarly apply to successive reorganizations, mergers, consolidations
and sales.

(f) No Impairment. The Company will not, by amendment of its Articles of Incorporation or through any
reorganization, transfer of assets, consolidation, merger, dissolution, issue or sale of securities or any other voluntary action, avoid or seek to avoid the observance or performance of any of the terms to be observed or performed hereunder by the
Company but will at all times in good faith assist in the carrying out of all the provisions of this Section and in the taking of all such action as may be necessary or appropriate in order to protect the conversion rights of the Holder against
dilution or other impairment. Without limiting the generality of the foregoing, the Company will not issue any capital stock of any class which is preferred as to dividends or as to the distribution of assets upon the voluntary or involuntary
dissolution, liquidation or winding up of the Company.

(g) Notice of Adjustments. Whenever this Warrant shall be
adjusted pursuant to this Section 4, the Company shall make a certificate signed by an officer of the Company setting forth, in reasonable detail, the event requiring the adjustment, the amount of the adjustment, the method by which such
adjustment was calculated, and the new Warrant Price and the type or the number of Shares purchasable after giving effect to such adjustment, and shall cause copies of such certificate to be mailed (by first class mail, postage prepaid) to the
Holder.

5. The Companys Obligation to Make Payments.

(a) Dividends and Distributions. In the event the Company at any time or from time to time after the date hereof shall make or
issue a dividend or other distribution, whether payable in cash, securities or other property of the Company, with respect to any of its capital stock for which an adjustment is not made pursuant to Section 4 of this Warrant, then and in
each such event, the Company shall concurrently make a cash payment to the Holder equal to the product of (i) the quotient obtained by dividing (x) the amount of cash plus the fair value of any property or securities distributed by
(y) the number of shares of Common Stock outstanding on the record date for such dividend or distribution and (ii) the number of Shares on such record date.

(b) Redemption of Capital Stock. In the event the Company at any time or from time to time after the date hereof shall repurchase
or redeem any of its capital stock or any rights, including without limitation, options, warrants or other convertible or exchangeable securities, to acquire such capital stock, then and in each such event, the Company shall concurrently make a cash
payment to the Holder equal to the product of (i) the quotient obtained by dividing (x) the aggregate amount of cash and the aggregate fair value of any



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property paid out by the Company in connection with any such repurchase or redemption by (y) the number of shares of Common Stock outstanding on a fully
diluted basis immediately after such repurchase or redemption and (2) the number of Shares.

6. Notice of Record Date. In the
event:



| | (1) | that the Company declares a dividend (or any other distribution) on any of its capital stock (including without limitation, its Common Stock);
| | --- | ----------------------------------------------------------------------------------------------------------------------------------------------



| | (2) | that the Company repurchases or redeems any of its capital stock (including without limitation, its Common Stock) or any rights to acquire such capital stock;
| | --- | --------------------------------------------------------------------------------------------------------------------------------------------------------------



| | (3) | that the Company subdivides or combines its outstanding shares of Common Stock;
| | --- | -------------------------------------------------------------------------------



| | (4) | of any reclassification of the Common Stock, or of any consolidation, merger or share exchange of the Company into or with another entity, or of the sale of all or substantially all
of the assets of the Company;
| | --- | -------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------



| | (5) | of the involuntary or voluntary dissolution, liquidation or winding up of the Company; or
| | --- | -----------------------------------------------------------------------------------------



| | (6) | of any offer of its Common Stock or any rights to acquire such Common Stock for consideration paid per share of Common Stock less than the Warrant Price then in effect.
| | --- | ------------------------------------------------------------------------------------------------------------------------------------------------------------------------

then the Company shall notify the Holder at least 30 days prior to the date specified in (A), (B) or (C) below, in writing
stating:

(A) the record date of such dividend, distribution, repurchase, redemption, subdivision or combination, or, if a
record is not to be taken, the date as to which the holders of Common Stock of record to be entitled to such dividend, distribution, repurchase, redemption, subdivision or combination are to be determined;

(B) the date on which such reclassification, consolidation, merger, share exchange, sale, dissolution, liquidation or winding up is
expected to become effective, and the date as of which it is expected that holders of Common Stock of record shall be entitled to exchange their shares of Common Stock for securities or other property deliverable upon such reclassification,
consolidation, merger, sale, dissolution or winding up; or

(C) the date on which such offering of its Common Stock or any
rights to acquire such Common Stock for consideration paid per share of Common Stock less than the Warrant Price is expected to become consummated.

7. Compliance with Securities Act; Disposition of Warrant or Common Stock.

(a) Compliance with
Securities Act. The Holder, by acceptance hereof, agrees that this Warrant and the Shares to be issued upon exercise hereof are being acquired for investment and that such Holder will not offer, sell or otherwise dispose of this Warrant
or any Common Stock to be issued upon exercise hereof except under circumstances which will not result in a violation of the Securities Act of 1933, as amended (the Act). All Shares issued upon exercise of this Warrant (unless
registered under the Act or sold or transferred pursuant to Rule 144 promulgated under the Act) shall be stamped or imprinted with a legend in substantially the following form:

THIS SECURITY HAS NOT BEEN REGISTERED UNDER THE SECURITIES ACT OF 1933 OR THE SECURITIES ACTS OF ANY STATE AND MAY NOT BE SOLD OR TRANSFERRED UNLESS
THERE IS AN EFFECTIVE REGISTRATION STATEMENT UNDER SUCH ACTS COVERING THIS SECURITY OR PURSUANT TO AN EXEMPTION FROM THE REGISTRATION AND PROSPECTUS DELIVERY REQUIREMENTS OF SUCH ACTS.

(b) Disposition of Warrant or Shares. Subject to the terms and conditions of this Warrant and applicable securities laws, this
Warrant and the rights represented by this Warrant may be transferred, assigned or pledged, in whole or in part with prior written notice to the Company. Any transfer shall be accompanied by the Notice of Transfer form attached hereto as Exhibit
B.



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8. Rights as Shareholders. The Holder shall not, by virtue hereof, be entitled to any rights of a
shareholder in the Company, either at law or equity, and the rights of the Holder are limited to those expressed in this Warrant and are not enforceable against the Company except to the extent set forth herein.

9. Representations and Warranties. The Company represents and warrants to the Holder as follows:

(a) This Warrant has been duly authorized and executed by the Company and is a valid and binding obligation of the Company enforceable in
accordance with its terms;

(b) The Shares have been duly authorized and reserved for issuance by the Company and, when
issued in accordance with the terms hereof, will be validly issued, fully paid and nonassessable;

(c) The rights,
preferences, privileges and restrictions granted to or imposed upon the Shares and the holders thereof are as set forth in the Companys Certificate of Incorporation;

(d) The execution and delivery of this Warrant are not, and the issuance of the Shares upon exercise of this Warrant in accordance with
the terms hereof will not be, inconsistent with the Companys Articles of Incorporation or by-laws, do not and will not contravene any law, governmental rule or regulation, judgment or order applicable to the Company, and, except for consents
that have already been obtained by the Company, do not and will not conflict with or contravene any provision of, or constitute a default under, any indenture, mortgage, contract or other instrument of which the Company is a party or by which it is
bound or require the consent or approval of, the giving of notice to, the registration with or the taking of any action in respect of or by, any federal, state or local government authority or agency or other person; and

10. Modification and Waiver. This Warrant and any provision hereof may be changed, waived, discharged or terminated only by an instrument in
writing signed by the party against which enforcement of the same is sought.

11. Notices. Except as otherwise expressly provided
herein, all notices and other communications provided for hereunder shall be in writing (including telegraphic, telex, telecopier or cable communication) and mailed, telegraphed, telexed, telecopied, cabled or delivered to the applicable party at
its address specified opposite its signature below, or at such other address as shall be designated by such party in a written notice to the other. All such notices and communications shall, when mailed, telegraphed, telexed, telecopied or cabled or
sent by overnight courier, be effective when deposited in the mails, delivered to the telegraph company, cable company or overnight courier, as the case may be, or sent by telex or telecopier.

12. Descriptive Headings. The descriptive headings of the several sections of this Warrant are inserted for convenience only and do not constitute
a part of this Warrant.

13. Governing Law. THIS WARRANT AND THE RIGHTS AND OBLIGATIONS OF THE PARTIES HEREUNDER SHALL BE GOVERNED
BY, AND CONSTRUED AND ENFORCED IN ACCORDANCE WITH, THE LAWS OF THE STATE OF CALIFORNIA.

14. Binding Effect on Successors. This
Warrant shall be binding upon any entity succeeding the Company by merger, consolidation or acquisition of all or substantially all of the Companys assets, and all of the obligations of the Company relating to the Common Stock issuable upon
the exercise of this Warrant shall survive the exercise, and termination of this Warrant and all of the covenants and agreements of the Company shall inure to the benefit of the successors and assigns of the Holder.

15. Severability. In case any one or more of the provisions contained in this Warrant shall be invalid, illegal or unenforceable in any respect,
the validity, legality and enforceability of the remaining provisions contained herein shall not in any way be affected or impaired thereby. The parties shall endeavor in good faith negotiations to replace the invalid, illegal or unenforceable
provisions with valid provisions, the economic effect of which comes as close as possible to that of the invalid, illegal or unenforceable provisions.



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16. Lost Warrants or Stock Certificates. The Company covenants to the Holder that upon receipt of
evidence reasonably satisfactory to the Company of the loss, theft, destruction, or mutilation of this Warrant or any stock certificate and, in the case of any such loss, theft or destruction, upon receipt of an indemnity reasonably satisfactory to
the Company, or in the case of any such mutilation upon surrender and cancellation of such Warrant or stock certificate, the Company will make and deliver a new Warrant or stock certificate, of like tenor, in lieu of the lost, stolen, destroyed or
mutilated Warrant or stock certificate.

IN WITNESS WHEREOF, the Company has caused this Warrant to be executed and delivered by its duly
authorized officer on the day and year first above written.



BIOLARGO, INCBy:


Name:

Dennis Calvert, President


Address:

2603 Main Street, Suite 1155Irvine, California 92614Attention: Dennis CalvertFacsimile: 949/666-7297




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|-------------------------- |  | 
|ACKNOWLEDGED AND ACCEPTED:
|                           | 
|By:                        |  | 

|            |  | 
|----------- |  | 
|            | 
|Print Name: |  | 

|         |  | 
|-------- |  | 
|         | 
|Address: |  | 
|         | 
|         |  | 
|         | 
|         |  | 



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EXHIBIT A

NOTICE OF EXERCISE

TO:    BIOLARGO, INC.

(1) The undersigned hereby elects to purchase
                    shares of Common Stock of BIOLARGO, INC. pursuant to the terms of the attached Warrant, and, unless such Warrant allows the
exercise to be cashless, tenders herewith payment of the Warrant Price for such shares in full.

(2) Please issue a certificate
or certificates representing said shares of Common Stock in the name of the undersigned or in such other name as is specified below:

(Name)(Name)


(3) Please issue a new Warrant for the unexercised portion of the attached Warrant in the
name of the undersigned or in such other name as is specified below:



(Name)(Address)(Social Security No.)(Signature)(Date)




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EXHIBIT B

NOTICE OF TRANSFER

(To be signed only upon transfer of Warrant)

FOR VALUE RECEIVED, the undersigned hereby sells, assigns and transfers unto
                            the right represented by the attached Warrant to purchase
                            shares of the Common Stock of BIOLARGO, INC., to which the attached Warrant
relates, and appoints                             as Attorney-in-fact to transfer such right on the books of
BIOLARGO, INC., with full power of substitution in the premises.

Dated:



(Signature must conform in all respects to the name of the Holder as specified on the face of the Warrant)(Address)


Signed in the presence
of:



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