ABOUT THIS PROSPECTUS

We urge you to read carefully this prospectus, together with the information incorporated herein by reference as described under the heading "Where You Can Find More Information," before buying any of the securities being offered.

Neither we nor any selling stockholder has authorized anyone to provide you with different information, and if anyone provides, or has provided you, with inconsistent information, you should not rely on it. The selling stockholders are offering to sell, and seeking offers to buy, shares of our common stock ("Common Stock"), only in jurisdictions where offers and sales are permitted. The information contained in this prospectus, as well as the information filed previously with the Securities and Exchange Commission (the "SEC"), and incorporated herein by reference, is accurate only as of the date of the document containing the information, regardless of the time of delivery of this prospectus or any applicable prospectus supplement or any sale of our Common Stock.

A prospectus supplement may add to, update or change the information contained in this prospectus. You should read both this prospectus and any applicable prospectus supplement together with additional information described below under the heading "Where You Can Find More Information." In this prospectus, references to the "Company," "S&W Seed," "registrant," "we," "us," and "our" refer to S&W Seed Company. The phrase "this prospectus" refers to this prospectus and any applicable prospectus supplement, unless the context requires otherwise.

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CAUTIONARY NOTE REGARDING FORWARD LOOKING STATEMENTS

This prospectus and any applicable prospectus supplement or free writing prospectus, including the documents that we incorporate by reference herein and therein, contain "forward-looking statements" within the meaning of Section 27A of the Securities Act of 1933, as amended (the "Securities Act"), and Section 21E of the Securities Exchange Act of 1934, as amended (the "Exchange Act"). These forward-looking statements can generally be identified as such because the context of the statement will include words such as "may," "will," "intend," "plan," "believe," "anticipate," "expect," "estimate," "predict," "potential," "continue," "likely," or "opportunity," the negative of these words or words of similar import. Similarly, statements that describe our future plans, strategies, intentions, expectations, objectives, goals or prospects are also forward-looking statements. Discussions containing these forward-looking statements may be found, among other places, in the "Business" and "Management's Discussion and Analysis of Financial Condition and Results of Operations" sections incorporated by reference from our most recent Annual Report on Form 10-K and our Quarterly Reports on Form 10-Q for the quarterly periods ended subsequent to our filing of such Annual Report on Form 10-K, as well as any amendments thereto reflected in subsequent filings with the SEC.

These forward-looking statements are based largely on our expectations and projections about future events and future trends affecting our business, and are subject to risks and uncertainties that could cause actual results to differ materially from those anticipated in the forward-looking statements. The risks and uncertainties include, among others, those noted in "Risk Factors" below and in any applicable prospectus supplement or free writing prospectus, and those included in the documents that we incorporate by reference herein and therein.

In addition, past financial and/or operating performance is not necessarily a reliable indicator of future performance, and you should not use our historical performance to anticipate results or future period trends. We can give no assurances that any of the events anticipated by the forward-looking statements will occur or, if any of them do, what impact they will have on our results of operations and financial condition. Except as required by law, we undertake no obligation to publicly revise our forward-looking statements to reflect events or circumstances that arise after the filing of this prospectus or any applicable prospectus supplement or free writing prospectus, or documents incorporated by reference herein and therein, that include forward-looking statements.

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PROSPECTUS SUMMARY

Founded in 1980 and headquartered in the Central Valley of California, we are a global agricultural company. Grounded in our historical expertise and what we believe is our present leading position in the breeding, production and sale of alfalfa seed, we continue to build towards our goal of being recognized as the world's preferred proprietary forage, grain and specialty crop seed company. In addition to our primary activities in alfalfa seed, we have recently expanded our product portfolio by adding hybrid sorghum and sunflower seed, which complement our alfalfa seed offerings by allowing us to leverage our infrastructure, research and development expertise and our distribution channels, as we begin to diversify into what we believe are higher margin opportunities. We also continue to conduct our stevia breeding program, having filed two additional patent applications in fiscal 2016.

Following our initial public offering in fiscal year 2010, we expanded certain pre-existing business initiatives and added new ones, including:

• diversifying our production geographically by expanding from solely producing seed in the San Joaquin Valley of California to initially adding production capability in the Imperial Valley of California, then expanding into Australia (primarily South Australia) and, most recently, adding production in other western U.S. states and Canada;
• expanding from solely offering non-dormant seed varieties to now having a full range of both dormant and non-dormant seed varieties;
• teaming with Forage Genetics International, LLC, a subsidiary of Land O' Lakes, Inc., to develop GMO alfalfa seeds;
• expanding the depth and breadth of our research and development capabilities in order to develop new varieties of both dormant and non-dormant alfalfa seed with traits sought after by our existing and potential customers;
• diversifying into complementary proprietary crops by acquiring the assets of a Queensland, Australia company specializing in breeding and licensing of hybrid sorghum and sunflower seed;
• expanding our distribution channels and customer base, initially through the acquisition of the customer list of a key international customer in the Middle East in July 2011, and thereafter, through certain strategic acquisitions;
• expanding our sales geographically both through the expansion of our product offerings to make available product needed in regions we historically did not cover and through an expansion of our sales and marketing efforts generally; and
• implementing a stevia breeding program to develop new stevia varieties that incorporate the most desirable characteristics of this all-natural, zero calorie sweetener.

We have accomplished these expansion initiatives through a combination of organic growth and strategic acquisitions, foremost among them:

• the acquisition in July 2011 of certain intangible assets, including the customer information, related to the field seed and small grain business of Genetics International, Inc., which had previously operated in the Middle East and North Africa, or MENA, and which began our transition into selling directly to MENA distributors;
• the acquisition of Imperial Valley Seeds, Inc. in October 2012, which enabled us to expand production of non-GMO seed into California's Imperial Valley, thereby ensuring a non-GMO source of seed due to the prohibition on GMO crops in the Imperial Valley, as well as enabling us to diversify our production areas and distribution channels;
• the acquisition of a portfolio of dormant alfalfa seed germplasm in August 2012 to launch our entry into the dormant market;
• the acquisition of the leading local producer of non-dormant alfalfa seed in South Australia, Seed Genetics International Pty Ltd, or SGI, in April 2013, which greatly expanded our production capabilities and geographic diversity;
• the acquisition of the alfalfa production and research facility assets and conventional (non-GMO) alfalfa germplasm from DuPont Pioneer, a wholly-owned subsidiary of E.I. du Pont de Nemours and Company, or DuPont Pioneer, in December 2014, thereby substantially expanding upon our initial entrance into the dormant alfalfa seed market that began in 2012 and enabling us to greatly expand our production and research and product development capabilities; and
• the acquisition, in May 2016, of the assets and business of SV Genetics Pty Ltd, or SV Genetics, a private Australian company specializing in the breeding and licensing of proprietary hybrid sorghum and sunflower seed germplasm, which represents our initial effort to diversify our product portfolio beyond alfalfa seed breeding and production and stevia research and development.

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We believe our 2013 combination with SGI created the world's largest non-dormant alfalfa seed company and gave us the competitive advantages of year-round production in that market. With the completion of the acquisition of dormant alfalfa seed assets from DuPont Pioneer in December 2014, we believe we have become the largest alfalfa seed company worldwide (by volume), with industry-leading research and development, as well as production and distribution capabilities in both hemispheres and the ability to supply proprietary dormant and non-dormant alfalfa seed. Our operations span the world's alfalfa seed production regions, with operations in the San Joaquin and Imperial Valleys of California, five additional western U.S. states, Australia and three provinces in Canada.

Our May 2016 acquisition of the hybrid sorghum and sunflower germplasm business and assets of SV Genetics signals management's commitment to our strategy of identifying opportunities to diversify our product lines and improve our gross margins.

From 1980 until 2009, our business was operated as a general partnership. We bought out the former partners beginning in June 2008, incorporated in Delaware in October 2009 and completed the buyout of the general partners in May 2010. We reincorporated in Nevada in December 2011. SGI, which is our wholly owned subsidiary, was incorporated as a limited proprietary corporation in South Australia in 1993, originally named Harkness Group. It then changed its name to Seed Genetics Australia Pty Ltd in 2002 and changed its name to Seed Genetics International Pty Ltd in 2011.

Our principal business office is located at 802 N. Douty Street, Hanford, California 93230, and our telephone is number (559) 884-2535. SGI's principal office space is located in Unley, South Australia. Our website address is www.swseedco.com. The information contained in or accessible through our website does not constitute part of this prospectus.

On July 19, 2017 (the "Closing Date"), we entered into a Securities Purchase Agreement (the "Purchase Agreement"), with certain purchasers named therein (the "Purchasers"), pursuant to which we agreed to sell and issue an aggregate of 2,685,000 shares of our Common Stock (the "Shares"), at a purchase price of $4.00 per share, for aggregate gross proceeds of $10.74 million.

In addition, as required by the Purchase Agreement, we and the Purchasers simultaneously entered into a Registration Rights Agreement (the "Registration Rights Agreement"), with respect to the Shares. Pursuant to the Registration Rights Agreement, we agreed to, among other things, (i) file a registration statement with the SEC within 30 days of the Closing Date to cover the resale of the Shares by the Purchasers, (ii) cause such registration statement to become effective as soon as practicable following the filing thereof and (iii) take all other actions as may be necessary to keep such registration statement continuously effective during the timeframes set forth in the Registration Rights Agreement. As set forth in the Registration Rights Agreement, if we fail to comply with certain obligations with respect to filing and securing effectiveness of such registration statement, we would be obligated to pay liquidated damages to the Purchasers in the amount of 1% of the aggregate purchase price of the Shares per month up to a maximum of 4% of the aggregate purchase price of the Shares so long as the event giving rise to the damages remains uncured, all as set forth in the Registration Rights Agreement.

The Registration Statement of which this prospectus is a part relates to the resales of the Shares issued to the Purchasers in connection with the Purchase Agreement, with such Purchasers being the selling stockholders.

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RISK FACTORS

An investment in our Common Stock involves a high degree of risk. Prior to making a decision about investing in our Common Stock, you should consider carefully the specific risk factors discussed in the sections entitled "Risk Factors" contained in our most recent Annual Report on Form 10-K or Quarterly Report on Form 10-Q, as filed with the SEC, which are incorporated in this prospectus by reference in their entirety, as well as any amendment or updates to our risk factors reflected in subsequent filings with the SEC, including any prospectus supplement hereto. These risks and uncertainties are not the only risks and uncertainties we face. Additional risks and uncertainties not presently known to us, or that we currently view as immaterial, may also impair our business. If any of the risks or uncertainties described in our SEC filings or any additional risks and uncertainties actually occur, our business, financial condition, results of operations and cash flow could be materially and adversely affected. In that case, the trading price of our Common Stock could decline and you might lose all or part of your investment.

The proceeds from the sale of shares of Common Stock offered pursuant to this prospectus are solely for the account of the selling stockholders. We will not receive any proceeds from the sale of shares by the selling stockholders.

The selling stockholders, or their pledgees, assignees, or successors-in-interest, are offering for resale, from time to time, up to an aggregate of 2,685,000 shares of our Common Stock. The following table sets forth certain information with respect to beneficial ownership of our Common Stock as of July 31, 2017 by the selling stockholders, as determined in accordance with Rule 13d-3 of the Exchange Act. This information has been obtained from the selling stockholders or in Schedules 13G or 13D and other public documents filed with the SEC.

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As discussed in greater detail above under the section "Prospectus Summary - Private Placement," on July 19, 2017, we entered into the Purchase Agreement with the selling stockholders pursuant to which we sold and issued the Shares to the selling stockholders and agreed with the selling stockholders to file a Registration Statement to enable the resale of the Shares. Except as noted in the footnotes to the Selling Stockholders table, none of the selling stockholders has held any position or office with us or our affiliates within the last three years or has had a material relationship with us or any of our predecessors or affiliates within the past three years, other than as a result of the ownership of our shares or other securities.

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PLAN OF DISTRIBUTION

The selling stockholders and any of their pledgees, assignees and successors-in-interest (each, a selling stockholder; provided, that a prospectus supplement naming any such pledgee, assignee or successor-in-interest has been filed with the SEC) may, from time to time, sell any or all of its securities covered hereby on the principal trading market or any other stock exchange, market or trading facility on which the securities are traded or in private transactions. The shares of common stock may be sold in one or more transactions at fixed prices, at prevailing market prices at the time of the sale, at varying prices determined at the time of sale, or at negotiated prices. The selling stockholders may use any one or more of the following methods when selling securities:

• on any national securities exchange or quotation service on which the securities may be listed or quoted at the time of sale;
• in the over-the-counter market;
• in transactions otherwise than on these exchanges or systems or in the over-the-counter market;
• through the writing of options, whether such options are listed on an options exchange or otherwise;
• ordinary brokerage transactions and transactions in which the broker-dealer solicits purchasers;
• block trades in which the broker-dealer will attempt to sell the securities as agent but may position and resell a portion of the block as principal to facilitate the transaction;
• purchases by a broker-dealer as principal and resale by the broker-dealer for its account;
• an exchange distribution in accordance with the rules of the applicable exchange;
• privately negotiated transactions;
• settlement of short sales;
• in transactions through broker-dealers that agree with the selling stockholders to sell a specified number of such securities at a stipulated price per security;
• through the writing or settlement of options or other hedging transactions, whether through an options exchange or otherwise;
• a combination of any such methods of sale; or
• any other method permitted pursuant to applicable law.

Broker-dealers engaged by the selling stockholders may arrange for other brokers-dealers to participate in sales. Broker-dealers may receive commissions or discounts from the selling stockholders (or, if any broker-dealer acts as agent for the purchaser of securities, from the purchaser) in amounts to be negotiated, but, except as set forth in a supplement to this prospectus, in the case of an agency transaction not in excess of a customary brokerage commission in compliance with FINRA Rule 2440; and in the case of a principal transaction a markup or markdown in compliance with FINRA IM-2440.

In connection with the sale of the securities or interests therein, the selling stockholders may enter into hedging transactions with broker-dealers or other financial institutions, which may in turn engage in short sales of the securities in the course of hedging the positions they assume. The selling stockholders may also sell securities short and deliver these securities to close out its short positions, or loan or pledge the securities to broker-dealers that in turn may sell these securities. The selling stockholders may also enter into option or other transactions with broker-dealers or other financial institutions or create one or more derivative securities which require the delivery to such broker-dealer or other financial institution of securities offered by this prospectus, which securities such broker-dealer or other financial institution may resell pursuant to this prospectus (as supplemented or amended to reflect such transaction).

The selling stockholders may pledge or grant a security interest in some or all of the shares of common stock owned by them and, if they default in the performance of their secured obligations, the pledgees or secured parties may offer and sell the shares of common stock from time to time pursuant to this prospectus or any amendment to this prospectus under Rule 424(b)(3) or other applicable provision of the Securities Act, amending, if necessary, the list of selling stockholders to include the pledgee, transferee or other successors in interest as selling stockholders under this prospectus. The selling stockholders also may transfer and donate the shares of common stock in other circumstances in which case the transferees, donees, pledgees or other successors in interest will be the selling beneficial owners for purposes of this prospectus.

The selling stockholders and any broker-dealers or agents that are involved in selling the securities may be deemed to be "underwriters" within the meaning of the Securities Act in connection with such sales. In such event, any commissions received by such broker-dealers or agents and any profit on the resale of the securities purchased by them may be deemed to be underwriting commissions or discounts under the Securities Act. Each selling stockholder has informed us that it does not have any written or oral agreement or understanding, directly or indirectly, with any person to distribute the securities.

We are required to pay certain fees and expenses incurred by us incident to the registration of the shares that may be sold pursuant to this prospectus. We have agreed to indemnify the selling stockholders against certain losses, claims, damages and liabilities, including liabilities under the Securities Act.

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The selling stockholders will be subject to the prospectus delivery requirements of the Securities Act including Rule 172 thereunder. In addition, any securities covered by this prospectus which qualify for sale pursuant to Rule 144 under the Securities Act may be sold under Rule 144 rather than under this prospectus. Each selling stockholder has advised us that there is no underwriter or coordinating broker acting in connection with the proposed sale of the resale securities by such selling stockholder.

We have agreed to keep the registration statement of which this prospectus is a part effective until the earlier of the date on which (a) the Shares have been sold or otherwise transferred pursuant to this prospectus; (b) such securities are sold in accordance with Rule 144 (or any successor provision) promulgated under the Securities Act; or (c) such securities become eligible for resale without volume or manner-of-sale restrictions and without current public information pursuant to Rule 144.

Under applicable rules and regulations under the Exchange Act, any person engaged in the distribution of the resale securities may not simultaneously engage in market making activities with respect to the common stock for the applicable restricted period, as defined in Regulation M, prior to the commencement of the distribution. In addition, the selling stockholders will be subject to applicable provisions of the Exchange Act and the rules and regulations thereunder, including Regulation M, which may limit the timing of purchases and sales of the common stock by the selling stockholders or any other person. We will make copies of this prospectus available to the selling stockholders and have informed them of the need to deliver a copy of this prospectus to each purchaser at or prior to the time of the sale (including by compliance with Rule 172 under the Securities Act).

Once sold under the registration statement, of which this prospectus forms a part, the Shares will be freely tradable in the hands of persons other than our affiliates.

The consolidated financial statements incorporated in this prospectus by reference to the Annual Report on Form 10-K for the fiscal year ended June 30, 2016, have been so incorporated in reliance on the report of Crowe Horwath LLP, independent registered public accounting firm, given on the authority of said firm as experts in auditing and accounting.

The validity of the Shares to be offered for resale by the selling stockholders under this prospectus will be passed upon for us by Jolie Kahn, Esq., Philadelphia, Pennsylvania.

The SEC allows us to "incorporate by reference" information that we file with it, which means that we can disclose important information to you by referring you to those documents. The information incorporated by reference is an important part of this prospectus. Information in this prospectus supersedes information incorporated by reference that we filed with the SEC prior to the date of this prospectus, while information that we file later with the SEC will automatically update and supersede the information in this prospectus. We also incorporate by reference into this prospectus the following documents as well as all documents (other than current reports or portions thereof furnished under Item 2.02 or Item 7.01 of Form 8-K and exhibits filed on such form that are related to such items and other portions of documents that are furnished, but not filed, pursuant to applicable rules promulgated by the SEC) that are filed by us with the SEC pursuant to Sections 13(a), 13(c), 14 or 15(d) of the Exchange Act (i) after the date of the initial filing of the registration statement of which this prospectus is a part and prior to effectiveness of the registration statement, and (ii) after the effectiveness of the registration statement but prior to the termination of the offering of the securities covered by this prospectus:

• our Annual Report on Form 10-K for the fiscal year ended June 30, 2016, filed with the SEC on September 15, 2016;
• the information specifically incorporated by reference into our Annual Report on Form 10-K for the fiscal year ended June 30, 2016, from our Definitive Proxy Statement on Schedule 14A relating to our 2016 Annual Meeting of Stockholders, filed with the SEC on October 28, 2016;
• our Quarterly Reports on Form 10-Q for the quarters ended September 30, 2016, December 31, 2016 and March 31, 2017, filed with the SEC on November 10, 2016, February 9, 2017 and May 11, 2017, respectively;
• our Current Reports on Form 8-K filed with the SEC on October 6, 2016, December 14, 2016 , January 17, 2017, March 17, 2017, June 26, 2017, July 20, 2017 and July 21, 2017; and
• the description of our common stock contained in our registration statement on Form 8-A, filed with the SEC on April 23, 2010, including any amendments and reports filed for the purpose of updating such description.

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You may request a copy of all documents that are incorporated by reference in this prospectus by writing or telephoning us at the following address and number: S&W Seed Company, 802 N. Douty Street, Hanford, CA 93230; telephone (559) 884-2535. We will provide copies of all documents requested (not including exhibits to those documents, unless the exhibits are specifically incorporated by reference into those documents or this prospectus) without charge.

In accordance with Rule 412 of the Securities Act, any statement contained in a document incorporated by reference herein shall be deemed modified or superseded to the extent that a statement contained herein or in any other subsequently filed document which also is or is deemed to be incorporated by reference herein modifies or supersedes such statement.

This prospectus, which constitutes a part of the registration statement, does not contain all of the information set forth in the registration statement or the exhibits which are part of the registration statement. For further information with respect to us and the securities offered by this prospectus, we refer you to the registration statement and the exhibits filed as part of the registration statement. We file annual, quarterly and current reports, proxy statements and other information with the SEC. You may read and copy any document we file with the SEC at the SEC's public reference room at 100 F Street, N.E., Washington, D.C. 20549. Please call the SEC at 1.800.SEC.0330 for further information on the operation of the public reference room. Our SEC filings are also available to the public at the SEC's website at www.sec.gov. We also maintain a website at www.swseedco.com. The information contained in, or that can be accessed through, our website is not part of this prospectus.