The discussion and table above do not take into account further dilution to investors in this offering that could occur upon the exercise of outstanding options and warrants having a per share exercise price less than the subscription price per share in this offering.

The number of shares of our outstanding common stock reflected in the discussion and table above is based on 17,979,681 shares of common stock outstanding as of June 30, 2017 and excludes, as of that date:

• 990,528 shares of our common stock issuable upon exercise of outstanding options at a weighted average exercise price of $5.12 per share;
• 120,971 shares of our common stock issuable upon the settlement of outstanding restricted stock units;
• 2,699,999 shares of our common stock issuable upon exercise of outstanding warrants at an exercise price of $4.53 per share (as may be adjusted pursuant to their terms); and
• 561,278 shares of our common stock to be reserved for potential future issuance pursuant to Amended and Restated 2009 Equity Incentive Plan.

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Our authorized capital stock consists of 50,000,000 shares of common stock and 5,000,000 shares of preferred stock, all with a par value of $0.001 per share. As of October 2, 2017, we had 20,704,688 shares of common stock and no shares of preferred stock outstanding.

Holders of our common stock are entitled to one vote for each share held on all matters submitted to a vote of stockholders. Subject to the preference in dividend rights of any series of preferred stock that we may issue in the future, the holders of common stock are entitled to receive such cash dividends, if any, as may be declared by our board of directors out of legally available funds. Upon liquidation, dissolution or winding up, after payment of all debts and liabilities and after payment of the liquidation preferences of any shares of preferred stock then outstanding, the holders of the common stock will be entitled to participate pro rata in all assets that are legally available for distribution.

Other than the rights described above, the holders of common stock have no preemptive subscription, redemption, sinking fund or conversion rights and are not subject to further calls or assessments. The rights and preferences of holders of common stock will be subject to the rights of any series of preferred stock that we may issue in the future.

We have never had, and immediately following this offering we will not have, any shares of preferred stock outstanding. Our board of directors, without any further vote or action by our stockholders, has the authority to issue up to an aggregate of 5,000,000 shares of preferred stock from time to time, in one or more classes or series of shares, on terms that it may determine, including among other things:

• its dividend rate; 
• its liquidation preference; 
• whether or not the shares will be convertible into, or exchangeable for, any other securities; and 
• whether or not the shares will have voting rights, and, if so, determine the extent of the voting powers and the conditions under which the shares will vote as a separate class.

We believe that our board of directors' ability to issue preferred stock on such a wide variety of terms will enable the preferred stock to be used for important corporate purposes, such as financing acquisitions or raising additional capital. However, were it inclined to do so, our board of directors could issue all or part of the preferred stock with, among other things, substantial voting power or advantageous conversion rights. This stock could be issued to persons deemed by our board of directors likely to support our current management in a context for control of us, either as a precautionary measure or in response to a specific takeover threat. We have no current plans to issue preferred stock for any purpose.

The issuance of preferred stock may delay, deter or prevent a change in control.

We are subject to Section 78.438 of the Nevada Revised Statutes, an anti-takeover law. In general, Section 78.438 prohibits a Nevada corporation from engaging in any business combination with any interested stockholder for a period of three years following the date that the stockholder became an interested stockholder, unless prior to that date, the board of directors of the corporation approved either the business combination or the transaction that resulted in the stockholder becoming an interested stockholder. Section 78.439 provides that business combinations after the three year period following the date that the stockholder becomes an interested stockholder may also be prohibited unless approved by the corporation's directors or other stockholders or unless the price and terms of the transaction meet the criteria set forth in the statute.

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Section 78.416 defines "business combination" to include the following:

• any merger or consolidation involving the corporation and the interested stockholder or any other corporation which is an affiliate or associate of the interested stockholder;
• any sale, transfer, pledge or other disposition of the assets of the corporation involving the interested stockholder or any affiliate or associate of the interested stockholder if the assets transferred have a market value equal to 5% or more of all of the assets of the corporation or 5% or more of the value of the outstanding shares of the corporation or represent 10% or more of the earning power of the corporation;
• subject to certain exceptions, any transaction that results in the issuance or transfer by the corporation of any stock of the corporation with a market value of 5% or more of the value of the outstanding shares of the corporation;
• the adoption of a plan of liquidation proposed by or under any arrangement with the interested stockholder or any affiliate or associate of the interested stockholder;
• any transaction involving the corporation that has the effect of increasing the proportionate share of the stock of any class or series of the corporation beneficially owned by the interested stockholder or any affiliate or associate of the interested stockholder; or
• the receipt by the interested stockholder or any affiliate or associate of the interested stockholder of the benefit of any loans, advances, guarantees, pledges or other financial benefits provided by or through the corporation.

In general, Section 78.423 defines an interested stockholder as any entity or person beneficially owning, directly or indirectly, 10% or more of the outstanding voting stock of the corporation and any entity or person affiliated with or controlling or controlled by any of these entities or persons.

Control Share Acquisitions.

The Nevada Business Corporation Law contains a provision governing "Acquisition of Controlling Interest." This law provides generally that any person or entity that acquires 20% or more of the outstanding voting shares of a publicly-held Nevada corporation in the secondary public or private market may be denied voting rights with respect to the acquired shares, unless a majority of the disinterested stockholders of the corporation elects to restore such voting rights in whole or in part. The control share acquisition act provides that a person or entity acquires "control shares" whenever it acquires shares that, but for the operation of the control share acquisition act, would bring its voting power within any of the following three ranges: (1) 20 to 33 1/3%, (2) 33 1/3 to 50%, or (3) more than 50%. A "control share acquisition" is generally defined as the direct or indirect acquisition of either ownership or voting power associated with issued and outstanding control shares. The stockholders or board of directors of a corporation may elect to exempt the stock of the corporation from the provisions of the control share acquisition act through adoption of a provision to that effect in the Articles of Incorporation or Bylaws of the corporation. The control share acquisition act is applicable only to shares of "Issuing Corporations" as defined by the act. An Issuing Corporation is a Nevada corporation, which; (1) has 200 or more stockholders of record, with at least 100 of such stockholders being both stockholders of record and residents of Nevada; and (2) does business in Nevada directly or through an affiliated corporation.

At this time, we do not have 200 stockholders of record or 100 stockholders of record resident of Nevada. Notwithstanding, our Bylaws exempt our common stock from the control share acquisition act. Therefore, the provisions of the control share acquisition act do not apply to acquisitions of our shares.

Our transfer agent and registrar for our common stock is Transfer Online, Inc., Portland, Oregon. Transfer Online is also serving as the subscription agent and the information agent for the rights offering.

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We are distributing to the holders of our common stock and warrants to purchase our common stock (on an assumed as-exercised basis) as of 5:00 p.m., New York time, on                     , 2017, which is the record date for this rights offering, at no charge, non-transferable subscription rights to purchase shares of our common stock. You will receive                 subscription rights for each share of common stock you owned or are deemed to own, assuming exercise of the warrants, as applicable, as of 5:00 p.m., New York time, on the record date. The total number of subscription rights issued to each holder will be rounded down to the nearest whole number.

The subscription rights will be evidenced by subscription rights certificates. Each subscription right includes a basic subscription privilege and an oversubscription privilege which are described in greater detail below. Subscription rights may be exercised at any time during the subscription period, which commences on                     , 2017, through the expiration date for the rights offering, which is 5:00 p.m., New York time, on                     , 2017. You are not required to exercise any of your subscription rights.

We will distribute                 subscription rights to each holder of record of our common stock and warrants to purchase our common stock (on an as-exercised basis) for each share of common stock held (or deemed to be held) by such holder, together with the holders of the warrants, collectively, for purposes of the rights offering, "stockholders." The total number of subscription rights issued to each holder will be rounded down to the nearest whole number. Each whole subscription right will entitle you to purchase one share of common stock at a subscription price of $3.50 per share. You may exercise any number of your subscription rights, or you may choose not to exercise any subscription rights. The subscription privilege will allocate the rights to purchase up to 3,500,000 shares of common stock (the "offered pool"), allocated pro rata among the stockholders entitled to participate as of the record date. We will place into escrow the subscribed for shares in the "offered pool," pending completion of the oversubscription portion of the rights offering. See "- Oversubscription Privilege."

If any of our stockholders do not exercise all of the subscription rights issued to them in this rights offering, then each holder who has exercised subscription rights in full will have the opportunity to purchase additional shares of our common stock at the subscription price of $3.50 per share under the oversubscription right. By extending oversubscription rights to our stockholders, we are providing those holders who have exercised all of their subscription rights with an opportunity to purchase shares that are not purchased by other stockholders in this rights offering.

If sufficient shares of common stock are available, we will seek to honor your oversubscription request in full. If, however, there are not enough shares available to fully satisfy all oversubscription right requests, we will allocate the available shares of common stock pro rata among those stockholders exercising their oversubscription privilege in proportion to the product (rounded down so that the subscription price multiplied by the aggregate number of shares does not exceed the aggregate offering amount) obtained by multiplying the number of shares such stockholder subscribed for under the oversubscription privilege by a fraction the numerator of which is the number of unsubscribed shares and the denominator of which is the total number of shares sought to be subscribed for under the oversubscription privilege by all holders participating in such oversubscription. The subscription agent will return any excess payments by mail without interest or deduction as soon as reasonably practical after the expiration date.

In order to properly exercise your oversubscription privilege, you must deliver the subscription payment related to your oversubscription privilege prior to the expiration of the rights offering. Because we will not know the total number of unsubscribed shares prior to the expiration of the rights offering, if you wish to maximize the number of shares you purchase pursuant to your oversubscription privilege, you will need to deliver payment in an amount equal to the aggregate subscription price for the maximum number of shares of our common stock that may be available to you (i.e., for the maximum number of shares of common stock available to you, assuming you fully exercise your basic subscription privilege and are allotted the full amount of your oversubscription as elected by you).

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We can provide no assurance that you will actually be entitled to purchase the number of shares issuable upon the exercise of your oversubscription privilege in full at the expiration of the rights offering. We will not be able to satisfy your exercise of the oversubscription privilege if all of our stockholders exercise their basic subscription privileges in full, and we will only honor an oversubscription privilege to the extent a sufficient amount of shares of our common stock are available following the exercise of subscription rights under the basic subscription privileges.

To the extent the aggregate subscription price of the maximum number of unsubscribed shares available to you pursuant to the oversubscription privilege is less than the amount you actually paid in connection with the exercise of the oversubscription privilege, you will be allocated only the number of unsubscribed shares available to you, and any excess subscription payments received by the subscription agent will be returned promptly, without interest or penalty. To the extent the amount you actually paid in connection with the exercise of the oversubscription privilege is less than the aggregate subscription price of the maximum number of unsubscribed shares available to you pursuant to the oversubscription privilege, you will be allocated only the number of unsubscribed shares for which you actually paid in connection with the oversubscription privilege.

On the date of expiration of the rights offering, the subscription agent will determine the "oversubscription amount," which is the difference between 3,500,000 shares and the number of shares subscribed for pursuant to the basic subscription privilege. The subscription agent will have the amount of oversubscription requests that each stockholder has indicated it would like to "purchase." The subscription agent will allocate the oversubscription amount accordingly (i.e., if the total amount of oversubscription requests is less than the oversubscription amount, the oversubscription requests will be allocated in full; however, if the amount of oversubscription requests exceeds the oversubscription amount, the subscription agent will allocate the pool pro rata).

Our board of directors considered a number of factors in determining the price for the rights offering, including:

• the price per share at which a new investor and two of our major stockholders, MFP and Wynnefield Capital, Inc., purchased shares in a private placement in July 2017;
• "pass through" savings as a result of conducting the rights offering with no investment banking support;
• the price at which our stockholders might be willing to participate in the rights offering;
• the price per share at which MFP is willing to backstop the rights offering;
• historical and current trading prices for our common stock, including on a volume weighted average share price basis over certain periods; and
• the desire to provide an opportunity to our stockholders to participate in the rights offering on a pro rata basis. 

See "Risk Factors - The subscription price determined for the rights offering is not an indication of the fair value of our common stock."

A member of our board of directors, Alexander C. Matina, is Vice President of Investments of the general partner of MFP, one of the purchasers in the above referenced July 2017 private placement.

The subscription rights will expire at 5:00 p.m., New York time, on                     , 2017, unless we extend it. We reserve the right to extend the subscription period at our sole discretion. Any extension of the subscription period for more than 30 days will require MFP's prior written consent. If the expiration date of the rights offering is so extended, we will give oral or written notice to the subscription agent on or before the scheduled expiration date, and we will issue a press release announcing such extension no later than 9:00 a.m., New York City time, on the next business day after the most recently announced expiration of the rights offering. You must properly complete the subscription rights certificate distributed by the subscription agent and deliver it, along with the full subscription price, to the subscription agent prior to 5:00 p.m., New York time, on                     , 2017, unless the expiration date is extended. After the expiration of the rights offering period, all unexercised subscription rights will be null and void. We will not be obligated to honor any purported exercise of subscription rights which the subscription agent receives after the expiration of the offering, regardless of when you sent the documents regarding that exercise. Shares purchased in the rights offering will be issued, and any subscription payments for shares not allocated or validly purchased will be sent, as soon as practicable following the expiration date of the rights offering.

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Shares of Common Stock Outstanding After the Rights Offering

As of the record date, there were                 shares of our common stock outstanding. We will issue up to a maximum of 3,500,000 shares of common stock in the rights offering and/or pursuant to the Backstop Commitment. Based on the number of shares issued and outstanding as of the record date, if we issue all 3,500,000 shares of common stock available in this rights offering and/or pursuant to the Backstop Commitment, we would have                                 shares of common stock issued and outstanding following the completion of the rights offering. Assuming no change in the number of shares issued and outstanding as of the record date, the dilution from the rights offering would be approximately                 %.

The shares of our common stock are listed on the Nasdaq Capital Market under the symbol "SANW."

We are conducting the rights offering in order to raise additional capital and to improve and strengthen our financial position. We intend to use the net proceeds from the rights offering to fund our acquisition of GMO alfalfa assets from DuPont Pioneer and for general corporate purposes, including working capital and capital expenditures. In addition, we may use a portion of the net proceeds for the repayment of debt or refinancing of indebtedness or the acquisition of land, facilities, property or complementary products or companies.

In authorizing the rights offering, our board of directors considered and evaluated a number of factors, including:

• our current capital resources and our future need for additional liquidity and capital;
• the size and timing of the rights offering;
• the potential dilution to our current stockholders if they choose not to participate in the offering;
• alternatives available for raising capital, including debt and other forms of equity raises;
• the potential impact of the rights offering on the public float for our common stock;
• MFP's willingness to backstop the rights offering;
• that applicable NASDAQ marketplace rules do not require stockholder approval of the rights offering or the Backstop Commitment; and
• the fact that existing stockholders would have the opportunity to participate on a pro rata basis to purchase additional shares of common stock.

The net proceeds to us, after deducting estimated offering expenses, will be approximately $                , assuming all 3,500,000 shares are issued in the rights offering and/or pursuant to the Backstop Commitment. We estimate that the expenses of the rights offering will be approximately $                .

We have entered into an Investment Agreement with MFP, pursuant to which MFP has agreed to provide the Backstop Commitment. The unsubscribed shares sold to MFP, if any, will be issued in a private placement. Accordingly, such shares would not be registered pursuant to the registration statement of which this prospectus forms a part, although we have agreed to register such shares in a separate registration statement. One of our directors, Alexander C. Matina, is Vice President of Investments of the general partner of MFP. For more information, see the section entitled "Description of the Backstop Commitment" of this prospectus.

Subject to your ability to exercise the oversubscription privilege, you may only purchase the number of whole shares of common stock purchasable upon exercise of the basic subscription privilege included in the subscription rights distributed to you in the rights offering. Accordingly, the number of shares of common stock that you may purchase in the rights offering is limited by the number of our shares of common stock or warrants to purchase our common stock you held on the record date. Although stockholders that fully and properly exercise their basic subscription privilege have the right to exercise the oversubscription privilege, there can be no assurances of the number of shares, if any, that a holder will be able to acquire through the exercise of the oversubscription privilege. We reserve the right to reject any or all subscriptions not properly submitted or the acceptance of which would, in the opinion of our counsel, be unlawful.

In addition, we will not be required to issue to you shares of our common stock pursuant to the rights offering if, in our opinion, you are required to obtain prior clearance or approval from any state or federal regulatory authorities to own or control the shares and if, at the time the rights offering expires, you have not obtained this clearance or approval.

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Method of Exercising Subscription Rights

The exercise of subscription rights is irrevocable and may not be cancelled or modified. You may exercise your subscription rights as follows:

To exercise your subscription privilege, you must properly complete and execute the subscription rights certificate, together with any required signature guarantees, and forward it, together with payment in full of the subscription price for each share of our common stock you are subscribing for, to the subscription agent at the address set forth under "- Subscription Agent and Information Agent" below, on or prior to the expiration date.

If you are a beneficial owner of shares that holds your shares through a broker, custodian bank or other nominee, we will ask your broker, custodian bank or other nominee to notify you of the rights offering. If you wish to exercise your subscription rights, you will need to have your broker, custodian bank or other nominee act for you and exercise your subscription rights and deliver all documents and payment on your behalf prior to 5:00 p.m., New York time, on                     , 2017. If you hold certificates of our common stock directly and would prefer to have your broker, custodian bank or other nominee act for you, you should contact your nominee and request it to effect the transactions for you.

To indicate your decision with respect to your subscription rights, you should complete and return to your broker, custodian bank or other nominee, the form entitled "Beneficial Owner Election Form." You should receive this form from your broker, custodian bank or other nominee with the other subscription rights offering materials. You should contact your broker, custodian bank or other nominee if you do not receive this form, but you believe you are entitled to participate in the rights offering. We are not responsible if you do not receive the form from your broker, custodian bank or nominee or if you receive it without sufficient time to respond.

Your signature on each subscription rights certificate must be guaranteed by an eligible institution, such as a member firm of a registered national securities exchange or a member of the Financial Industry Regulatory Authority, or a commercial bank or trust company having an office or correspondent in the United States, subject to standards and procedures adopted by the subscription agent, unless:

• you are a record holder and your subscription rights certificate provides that shares are to be delivered to you as record holder of those subscription rights; or
• you are an eligible institution.

You should read the instruction letter accompanying the subscription rights certificate carefully and strictly follow it. Do not send subscription rights certificates or payments to us. We will not consider your subscription received until the subscription agent has received delivery of a properly completed and duly executed subscription rights certificate and payment of the full subscription amount. The risk of delivery of all documents and payments is borne by you or your nominee, not us or the subscription agent.

The method of delivery of subscription rights certificates and payment of the subscription amount to the subscription agent will be at the risk of the holders of subscription rights. If sent by mail, we recommend that you send those certificates and payments by overnight courier or by registered mail, properly insured, with return receipt requested, and that a sufficient number of days be allowed to ensure delivery to the subscription agent and clearance of payment before the expiration of the subscription period for the rights offering.

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Validity of Subscriptions

We will resolve all questions regarding the validity and form of the exercise of your subscription privileges, including time of receipt and eligibility to participate in the rights offering. Our determination will be final and binding. Once made, subscriptions and directions are irrevocable, and we will not accept any alternative, conditional or contingent subscriptions or directions. We reserve the absolute right to reject any subscriptions or directions not properly submitted or the acceptance of which would be unlawful. You must resolve any irregularities in connection with your subscriptions before the subscription period expires, unless waived by us at our sole discretion. Neither the subscription agent nor we shall be under any duty to notify you or your representative of defects in your subscriptions. A subscription will be considered accepted, subject to our right to cancel the rights offering, only when a properly completed and duly executed subscription rights certificate and any other required documents and payment of the full subscription amount have been received by the subscription agent. Our interpretations of the terms and conditions of the rights offering will be final and binding.

Once you submit the form of subscription rights certificate to exercise any subscription rights, you are not allowed to revoke or change the exercise or request a refund of monies paid. All exercises of subscription rights are irrevocable, even if you learn information about us that you consider to be unfavorable. You should not exercise your subscription rights unless you are certain that you wish to purchase the shares of common stock offered pursuant to this rights offering.

Your payment of the subscription price must be made in U.S. dollars for the full number of shares of common stock you wish to acquire under the subscription privilege by either:

• wire transfer of immediately available funds to accounts maintained by the subscription agent;
• uncertified check payable to "Transfer Online, Inc. (acting as subscription agent for S&W Seed Company)";
• bank draft drawn upon a U.S. bank and payable to "Transfer Online, Inc. (acting as subscription agent for S&W Seed Company)"; or
• U.S. postal money order payable to "Transfer Online, Inc. (acting as subscription agent for S&W Seed Company)."

If you hold your rights through a broker, dealer, custodian bank or other nominee, you must deliver the applicable subscription payment and a completed form entitled "Beneficial Owner Election Form" (or such other appropriate documents as are provided by your nominee related to your subscription rights) to your nominee in each case, prior to the expiration of the rights offering.

The subscription agent will hold funds received in payment for shares of the common stock in a segregated account pending completion of the rights offering. The subscription agent will hold this money until the rights offering is completed or is cancelled. If the rights offering is cancelled for any reason, we will return this money to subscribers, without interest or penalty, as soon as practicable.

Your payment will be considered received by the subscription agent only upon:

• clearance of any uncertified check deposited by the subscription agent; or
• receipt by the subscription agent of any wire or bank draft drawn upon a U.S. bank or any U.S. postal money order.

Payment received after the expiration of the rights offering period will not be honored, and, in that case, the subscription agent will return your payment to you, without interest or penalty, as soon as practicable.

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Clearance of Uncertified Checks

If you are paying by uncertified personal check, please note that payment will not be deemed to have been received by the subscription agent until the check has cleared, which could take at least five or more business days to clear. If you wish to pay the subscription price by uncertified personal check, we urge you to make payment sufficiently in advance of the time the rights offering expires to ensure that your payment is received by the subscription agent and clears by the rights offering expiration date. We urge you to consider making your payment by wire transfer or, as an alternative, using a bank draft or U.S. postal money order.

If you do not indicate the number of basic and, if applicable, oversubscription rights being exercised or complete the other required information, or do not forward full payment of the total subscription price payment for the number of subscription rights that you indicate are being exercised, then you will be deemed to have exercised your subscription rights with respect to the maximum number of subscription rights that may be exercised with the aggregate subscription price payment you delivered to the subscription agent. If we do not apply your full subscription price payment to your purchase of shares of our common stock, we or the subscription agent will return the excess amount to you by mail, without interest or penalty, as soon as practicable after the expiration date of the rights offering.

The period for exercising your subscription rights may be extended by our board of directors in its reasonable discretion. Any extension of the subscription period for more than 30 days will require MFP's prior written consent. Our board of directors does not currently intend to extend the expiration of the rights offering.

If we cancel the rights offering, in whole or in part, all affected subscription rights will expire without value, and all subscription payments received by the subscription agent will be returned, without interest or penalty, as soon as practicable. If we cancel the rights offering, we will issue a press release notifying stockholders of the cancellation.

If you are a broker, custodian bank or other nominee holder that holds shares of our common stock for the account of others on the rights offering record date, you should notify the respective beneficial owners of such shares of the rights offering as soon as possible to learn their intentions with respect to exercising their subscription rights. You should obtain instructions from the beneficial owner with respect to their subscription rights, as set forth in the instructions we have provided to you for your distribution to beneficial owners. If the beneficial owner so instructs, you should complete the appropriate subscription rights certificates and submit them to the subscription agent with the proper payment. If you hold shares of our common stock for the account(s) of more than one beneficial owner, you may exercise the number of subscription rights to which all such beneficial owners in the aggregate otherwise would have been entitled had they been direct record holders of our common stock on the subscription rights offering record date, provided that you, as a nominee record holder, make a proper showing to the subscription agent by submitting the form entitled "Nominee Holder Certification" that we will provide to you with your subscription rights offering materials. If you did not receive this form, you should contact the subscription agent to request a copy.

The subscription rights granted to you are non-transferable and, therefore, you may not sell, transfer or assign your subscription rights to anyone else.

All shares that you purchase in the rights offering will be issued in book-entry, or uncertificated, form. When issued, the shares will be registered in the name of the subscription rights holder of record. As soon as practicable after the expiration of the rights offering, the subscription agent will arrange for the issuance of the shares of common stock purchased pursuant to the subscription privilege and oversubscription privilege. Subject to state securities laws and regulations, we have the discretion to delay distribution of any shares you may have elected to purchase by exercise of your subscription rights in order to comply with state securities laws.

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Rights of Subscribers

You will have no rights as a stockholder of our common stock until your account, or your account at your broker, custodian bank or other nominee is credited with the shares of our common stock purchased in the rights offering. You will have no right to revoke your subscriptions after you deliver your completed subscription rights certificate, payment and any other required documents to the subscription agent.

We will not mail subscription rights certificates to stockholders whose addresses are outside the United States or who have an army post office or foreign post office address. The subscription agent will hold these subscription rights certificates for their account. To exercise subscription rights, our foreign stockholders and stockholders with an army post office or foreign post office address must notify the subscription agent prior to 11:00 a.m., New York time, at least three business days prior to the expiration date of the rights offering and demonstrate to the satisfaction of the subscription agent that the exercise of such subscription rights does not violate the laws of the jurisdiction of such stockholder.

Our board of directors is making no recommendations regarding your exercise of the subscription rights. You are urged to make your own decision whether or not to exercise your subscription rights based on your own assessment of our business and the rights offering. See "Risk Factors" in this prospectus and in any document incorporated by reference into this prospectus.

We have not employed any brokers, dealers or underwriters in connection with the solicitation of exercise of rights, and, except as described herein, no other commissions, underwriting fees or discounts will be paid in connection with this rights offering.

Transfer Online, Inc. is acting as the subscription agent and information agent for the rights offering under an agreement with us. All subscription rights certificates, payments of the subscription price (other than wire transfers) and nominee holder certifications, to the extent applicable to your exercise of subscription rights, must be delivered to Transfer Online, Inc. as follows:

You should direct any questions or requests for assistance concerning the method of subscribing for the shares of common stock or for additional copies of this prospectus to Transfer Online, Inc. at (503) 227-2950.

We will pay the fees and expenses of Transfer Online, Inc., as subscription agent and information agent.

If you deliver subscription documents or subscription rights certificates in a manner different than that described in this prospectus, then we may not honor the exercise of your subscription privilege.

Transfer Online, Inc. will serve as escrow agent to hold the offered pool subscribed shares pending completion of the oversubscription portion of the rights offering. We will pay the fees and expenses of Transfer Online, Inc., in its capacity as escrow agent.

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Other Matters

We are not making the rights offering in any state or other jurisdiction in which it is unlawful to do so, nor are we distributing or accepting any offers to purchase any shares of our common stock from subscription rights holders who are residents of those states or other jurisdictions or who are otherwise prohibited by federal or state laws or regulations from accepting or exercising the subscription rights. We may delay the commencement of the rights offering in those states or other jurisdictions, or change the terms of the rights offering, in whole or in part, in order to comply with the securities laws or other legal requirements of those states or other jurisdictions. Subject to state securities laws and regulations, we also have the discretion to delay allocation and distribution of any shares you may elect to purchase by exercise of your subscription privileges in order to comply with state securities laws. We may decline to make modifications to the terms of the rights offering requested by those states or other jurisdictions, in which case, if you are a resident in those states or jurisdictions or if you are otherwise prohibited by federal or state laws or regulations from accepting or exercising the subscription rights you will not be eligible to participate in the rights offering.

If you have any questions or require assistance regarding the method of exercising your subscription rights or requests for additional copies of this document or the Instructions as to the Use of S&W Seed Company Subscription Rights Certificates distributed by the subscription agent, you should contact Transfer Online, Inc. at (503) 227-2950.

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Below is a brief summary of matters related to the Backstop Commitment.

Pursuant to the Investment Agreement, MFP has agreed to provide the Backstop Commitment. The unsubscribed shares sold to MFP, if any, are being offered and sold to MFP in a private placement, although we have agreed to register such shares in a separate registration statement.

MFP's obligation to provide the Backstop Commitment under the Investment Agreement is subject to customary conditions, including, but not limited to, the following: (i) the effectiveness of the registration statement of which this prospectus is a part; (ii) the rights offering being conducted in accordance with the terms and conditions of the Investment Agreement and this prospectus; (iii) MFP having received certain notices from us; (iv) all governmental and third party notifications, filings, consents, waivers and approvals required for the consummation of the transactions contemplated by the Investment Agreement having been made or received; (v) no legal impediment to the issuance of shares pursuant to the rights offering or the Backstop Commitment; (vi) us being in good standing as of the closing date of the rights offering and the other transactions contemplated by the Investment Agreement; (vii) the accuracy of our representations and warranties made in the Investment Agreement; (viii) our compliance in all material respects with our covenants made in the Investment Agreement; (ix) the absence of any changes or events that, individually or in the aggregate, would reasonably be expected to result in a material adverse effect (as defined in the Investment Agreement); (x) reimbursement of MFP's expenses in connection with the Investment Agreement; and (xi) the absence of certain adverse market events.

The Investment Agreement may be terminated at any time prior to the closing of the rights offering and the issuances contemplated by the Investment Agreement:

• by mutual written consent;

• by MFP, under the following circumstances: (i) if we breach any covenant or representation or warranty that would cause the failure to satisfy a closing condition and is not capable of being cured by February 28, 2018; (ii) if the rights offering has not commenced by February 28, 2018; (iii) after February 28, 2018, if the rights offering has not been completed by reason other than a breach by MFP of its obligations under the Agreement; or

• by us under the following circumstances: (i) if MFP breaches any covenant or representation or warranty that would cause the failure to satisfy a closing condition and is not capable of cure by February 28, 2018; or (ii) after February 28, 2018, if the rights offering has not been completed by reason other than our breach of our obligations under the Agreement.

We have agreed to indemnify MFP and its affiliates, and its and their respective officers, directors, members, partners, employees, agents and controlling persons for losses arising out of the rights offering, the Investment Agreement or any of the transactions contemplated by the Investment Agreement, subject to certain exceptions.

We are not paying a fee to MFP in connection with the Backstop Commitment. However, we have agreed to reimburse MFP for its reasonable costs and expenses, not to exceed $50,000 in the aggregate.

Pursuant to the Investment Agreement, MFP will receive certain customary registration rights with respect to the shares of common stock that it acquires under the Investment Agreement.

As of the record date, MFP owned                                 shares of common stock, representing approximately                 % of our issued and outstanding shares of common stock as of such date. Following completion of the rights offering and after giving effect to the Backstop Commitment, if no other stockholders exercise their subscription rights in the rights offering, MFP will own                                 shares of our common stock, representing approximately                 % of our issued and outstanding shares of common stock. One of our directors, Alexander C. Matina, is Vice President of Investments of the general partner of MFP.

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The following discussion is a summary of the material U.S. federal income tax consequences to U.S. Holders (as defined below) relating to the receipt and exercise (or expiration) of the subscription rights acquired through the rights offering and the ownership and disposition of shares of our common stock received upon exercise of the subscription rights.

This summary deals only with subscription rights acquired through the rights offering and shares of our common stock acquired upon exercise of subscription rights, in each case, that are held as capital assets by a beneficial owner. This discussion applies only to U.S. Holders and does not address all aspects of U.S. federal income taxation that may be relevant to U.S. Holders in light of their personal circumstances, including the alternative minimum tax and the Medicare contribution tax on investment income. This discussion also does not address tax consequences to U.S. Holders that may be subject to special tax rules, including, without limitation, insurance companies, real estate investment trusts, regulated investment companies, corporations that accumulate income to avoid U.S. federal income tax, grantor trusts, tax-exempt organizations, employee stock purchase plans, partnerships and other pass-through entities, persons holding subscription rights, shares of our common stock or warrants as part of a hedging, integrated, conversion or constructive sale transaction, a synthetic security or a straddle, or another risk reduction strategy, financial institutions, brokers, dealers in securities or currencies, traders that elect to mark-to-market their securities, persons that acquired subscription rights, shares of our common stock or warrants in connection with employment or other performance of services, and persons that have a functional currency other than the U.S. dollar. In addition, the discussion does not describe any tax consequences arising out of the tax laws of any state, local or foreign jurisdiction, or any U.S. federal tax considerations other than income taxation (such as estate, generation skipping or gift taxation).

The discussion below is based upon the provisions of the Internal Revenue Code of 1986, as amended, or the Code, the United States Treasury regulations promulgated thereunder, rulings and judicial decisions, as of the date hereof, and such authorities may be repealed, revoked or modified, perhaps retroactively. We have not sought, and will not seek, any rulings from the Internal Revenue Service, or the IRS, regarding the matters discussed below. There can be no assurance that the IRS or a court (if the matter were contested) will not take positions concerning the tax consequences of the receipt of subscription rights acquired through the rights offering by persons holding shares of our common stock or warrants, the exercise (or expiration) of the subscription rights, or the acquisition, ownership and disposition of shares of our common stock, in each case that are different from those discussed below.

As used herein, a "U.S. Holder" means a beneficial owner of shares of our common stock, warrants, subscription rights or shares of our common stock acquired upon exercise of subscription rights, as the case may be, that is for U.S. federal income tax purposes: (1) an individual who is a citizen or resident of the United States; (2) a corporation (or other entity treated as a corporation for U.S. federal income tax purposes) created or organized in or under the laws of the United States or any state thereof or the District of Columbia; (3) an estate the income of which is subject to U.S. federal income taxation regardless of its source; or (4) a trust (a) the administration of which is subject to the primary supervision of a court within the United States and one or more United States persons as described in Section 7701(a)(30) of the Code have authority to control all substantial decisions of the trust or (b) that has a valid election under the Treasury Regulations in effect to be treated as a United States person.

If any entity or arrangement that is treated as a partnership or other pass-through entity for U.S. federal income tax purposes is the record owner, the U.S. federal income tax treatment of a partner (or participant in another pass-through entity) generally will depend upon the status of the person and the activities of the entity. Holders that are partnerships or other pass-through entities (and partners in such partnerships and participants in such entities) are urged to consult their own tax advisors.

HOLDERS OF SHARES OF OUR COMMON STOCK OR WARRANTS SHOULD CONSULT THEIR OWN TAX ADVISORS REGARDING THE APPLICATION OF THE U.S. FEDERAL INCOME TAX LAWS TO THEIR PARTICULAR SITUATIONS AND THE CONSEQUENCES UNDER FEDERAL ESTATE AND GIFT TAX LAWS, FOREIGN, STATE AND LOCAL LAWS AND TAX TREATIES OF THE RECEIPT, OWNERSHIP AND EXERCISE OF SUBSCRIPTION RIGHTS AND THE ACQUISITION, OWNERSHIP AND DISPOSITION OF SHARES OF OUR COMMON STOCK ACQUIRED UPON EXERCISE OF SUBSCRIPTION RIGHTS.

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Taxation of Subscription Rights

Receipt of Subscription Rights

Although the authorities governing transactions such as this rights offering are complex and do not specifically address the consequences of certain aspects of this rights offering, including the distribution of subscription rights to warrant holders and the effects of the oversubscription privilege, we do not believe your receipt of subscription rights pursuant to the rights offering should be treated as a taxable distribution with respect to your existing shares of common stock or warrants for U.S. federal income tax purposes. Pursuant to Section 305(a) of the Code, in general, the receipt by a stockholder of a right to acquire stock should not be included in the taxable income of the recipient. For this purpose, rights to acquire stock are treated as stock, so that holders of warrants would be treated as stockholders. The general rule of non-recognition in Section 305(a) is subject to exceptions in Section 305(b), which include "disproportionate distributions." A disproportionate distribution is a distribution or a series of distributions, including deemed distributions, that has the effect of the receipt of cash or other property by some stockholders and an increase in the proportionate interest of other stockholders in a corporation's assets or earnings and profits. During the last 36 months, we have not made any distributions of cash or non-stock property with respect to: (i) our common stock or (ii) our options or warrants to acquire common stock. Currently we do not intend to make any future distributions of cash or non-stock property with respect to: (i) our common stock or (ii) our options or warrants to acquire our common stock; however, there is no guarantee that we will not make such distributions in the future.

Our position regarding the tax-free treatment of the subscription rights distribution is not binding on the IRS or the courts. If our position is finally determined by the IRS or a court to be incorrect, whether on the basis that the issuance of the subscription rights is a "disproportionate distribution" or otherwise, the fair market value of the subscription rights would be taxable to holders of our common stock as a dividend to the extent of the holder's pro rata share of our current and accumulated earnings and profits, if any, with any excess being treated as a tax-free return of capital to the extent of the stockholder's tax basis in our stock and then as capital gain. Although no assurance can be given, it is anticipated that we will not have current and accumulated earnings and profits through the end of 2017. Further, if our position is incorrect, the treatment of holders of warrants may differ from the treatment of the subscription rights distribution to the holders of our common stock. The warrant holders may be treated in a manner similar to holders of our common stock but it is possible that they may be subject to different and more adverse U.S. federal income tax consequences.

The following discussion is based upon the treatment of the subscription rights issuance as a non-taxable distribution with respect to your existing shares of common stock or warrants for U.S. federal income tax purposes.

If the fair market value of the subscription rights you receive in respect of your existing shares of common stock is less than 15% of the fair market value of your existing shares of common stock on the date you receive the subscription rights, the subscription rights will have a zero dollar basis for U.S. federal income tax purposes, unless you elect to allocate your basis in your existing shares of common stock between those existing holdings and the subscription rights in proportion to the relative fair market values of the existing holdings and the subscription rights, each determined on the date of receipt of the subscription rights. If you elect to allocate basis between your existing holdings and the subscription rights, you must make this election on a statement included with a timely filed tax return (including extensions) for the taxable year in which you receive the subscription rights. The election is irrevocable.

If the fair market value of the subscription rights you receive in respect of your existing shares common stock is 15% or more of the fair market value of your existing shares of common stock on the date you receive the subscription rights, then you must allocate the basis in your existing holdings between those holdings and the subscription rights in proportion to their fair market values determined on the date you receive the subscription rights. It is unclear whether the rules for allocating tax basis will apply in the same way to subscription rights received with respect to warrants. We urge you to consult with your own tax advisor as to the computation of the basis in subscription rights received with respect to our warrants.

The fair market value of the subscription rights on the date that the subscription rights are distributed is uncertain, and we have not obtained, and do not intend to obtain, an appraisal of the fair market value of the subscription rights on that date. In determining the fair market value of the subscription rights, you should consider all relevant facts and circumstances, including but not limited to any difference between the subscription price of the subscription rights and the trading price of our shares of common stock on the date that the subscription rights are distributed, the length of the period during which the subscription rights may be exercised and the fact that the subscription rights are non-transferable.

Generally, you will not recognize gain or loss upon the exercise of a subscription right received pursuant to the rights offering. Your adjusted tax basis in the shares of common stock acquired through the exercise of such subscription rights should equal the sum of (i) the subscription price paid for the shares, plus (ii) the tax basis, if any, in the subscription rights immediately prior to such exercise. The holding period for shares of common stock acquired upon exercise of such subscription rights will begin on the date the subscription right is exercised.

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If you exercise a subscription right received in the rights offering after disposing of the shares of our common stock or warrants with respect to which such subscription right is received, then certain aspects of the tax treatment of the exercise of the subscription right are unclear, including (1) the allocation of the tax basis between the shares of common stock or warrants previously sold and the subscription right, (2) the impact of such allocation on the amount and timing of gain or loss recognized with respect to the shares of our common stock or warrants previously sold and (3) the impact of such allocation on the tax basis of the shares of our common stock acquired upon exercise of the subscription right. If you exercise a subscription right received in the rights offering after disposing of shares of common stock or warrants with respect to which such subscription right is received, you should consult with your own tax advisor.

If you allow subscription rights received in the rights offering to expire, you should not recognize any gain or loss for U.S. federal income tax purposes, and you should re- allocate any portion of the tax basis in your existing shares of common stock or warrants previously allocated to the expired subscription rights to the existing shares of common stock or warrants.

Distributions

Distributions with respect to shares of our common stock acquired upon exercise of subscription rights will be taxable as dividend income when the distribution is actually or constructively received to the extent of our current or accumulated earnings and profits as determined for U.S. federal income tax purposes.

Dividend income received by certain non-corporate U.S. Holders with respect to shares of our common stock generally will be "qualified dividends" subject to preferential rates of U.S. federal income tax, provided that the U.S. Holder meets applicable holding period and other requirements. Subject to similar exceptions for short-term and hedged positions, dividend income on our shares of common stock paid to U.S. Holders that are domestic corporations generally will qualify for the dividends-received deduction. To the extent that the amount of a distribution exceeds our current and accumulated earnings and profits, the distribution will be treated first as a tax-free return of capital to the extent of your adjusted tax basis in your shares of our common stock and thereafter as capital gain.

If you sell or otherwise dispose of shares of common stock acquired upon exercise of subscription rights in a taxable transaction, you will generally recognize capital gain or loss equal to the difference between the amount realized and your adjusted tax basis in the shares. The capital gain or loss will be long-term capital gain or loss if your holding period for the shares is more than one year at the time of disposition. Long-term capital gain of a non-corporate U.S. Holder is generally taxed at preferential rates of U.S. federal income tax. The deductibility of capital losses is subject to limitations.

You may be subject to information reporting and/or backup withholding if you receive dividend payments (including constructive dividends) or receive gross proceeds from the disposition of shares of our common stock acquired through the exercise of subscription rights. Backup withholding (currently at the rate of 28%) may apply under certain circumstances if you (1) fail to furnish your social security or other taxpayer identification number, or TIN, (2) furnish an incorrect TIN, (3) fail to report interest or dividends properly or (4) fail to provide a certified statement, signed under penalty of perjury, that the TIN provided is correct, that you are not subject to backup withholding and that you are a U.S. person for U.S. federal income tax purposes on IRS Form W-9. Any amount withheld from a payment under the backup withholding rules is allowable as a credit against (and may entitle you to a refund with respect to) your U.S. federal income tax liability, provided that the required information is timely furnished to the IRS. Certain persons, including corporations and certain financial institutions, that demonstrate this fact, if requested, are exempt from information reporting and backup withholding. You are urged to consult your own tax advisor as to your qualification for exemption from backup withholding and the procedure for obtaining such exemption.

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THE PRECEDING DISCUSSION OF MATERIAL U.S. FEDERAL INCOME TAX CONSEQUENCES TO U.S. HOLDERS IS NOT TAX ADVICE. HOLDERS OF SUBSCRIPTION RIGHTS, SHARES OF OUR COMMON STOCK AND WARRANTS SHOULD CONSULT THEIR OWN TAX ADVISORS REGARDING THE APPLICATION OF THE U.S. FEDERAL INCOME TAX LAWS TO THEIR PARTICULAR SITUATIONS AND THE CONSEQUENCES UNDER FEDERAL ESTATE AND GIFT TAX LAWS, FOREIGN, STATE AND LOCAL LAWS AND TAX TREATIES OF THE RECEIPT, OWNERSHIP AND EXERCISE OF SUBSCRIPTION RIGHTS AND THE ACQUISITION, OWNERSHIP AND DISPOSITION OF SHARES OF OUR COMMON STOCK ACQUIRED UPON EXERCISE OF SUBSCRIPTION RIGHTS.

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We will distribute the subscription rights, subscription rights certificates and copies of this prospectus to persons who owned shares of our common stock or warrants to purchase our common stock of record as of 5:00 p.m., New York time, on                     , 2017, the record date for the rights offering. If you wish to exercise your subscription rights and purchase shares of common stock, you should complete the subscription rights certificate and return it with payment for the shares, to the subscription agent, Transfer Online, Inc. See "Description of the Rights Offering - Method of Exercising Subscription Rights." If you have any questions, you should contact the information agent, Transfer Online, Inc., at (503) 227-2950. The subscription rights will not be listed on any stock exchange or market or on the OTC Markets. Our shares of common stock are listed on the Nasdaq Capital Market under the symbol "SANW."

We have agreed to pay the subscription agent and information agent customary fees plus certain expenses in connection with the rights offering. We have not employed any brokers, dealers or underwriters in connection with the solicitation of exercise of subscription rights. Except as described in this section, we are not paying any other commissions, underwriting fees or discounts in connection with the rights offering. Some of our employees may solicit responses from you as a holder of subscription rights, but we will not pay our employees any commissions or compensation for these services other than their normal employment compensation. We estimate that our total expenses in connection with the rights offering will be approximately $         .

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             , 2017