In connection with the salesales of the securities, we,shares of common stock or otherwise, the purchasersselling stockholders may enter into hedging transactions with broker-dealers, which may in turn engage in short sales of the securities for whom the underwriter may act as agent, may compensate the underwritershares of common stock in the formcourse of underwriting discountshedging in positions they assume. The selling stockholders may also sell shares of common stock short and deliver shares of common stock covered by this prospectus to close out short positions and to return borrowed shares in connection with such short sales. The selling stockholders may also loan or commissions. The underwriterpledge shares of common stock to broker-dealers that in turn may sell the securities tosuch shares.

The selling stockholders may pledge or through dealers, and the underwriter may compensate those dealersgrant a security interest in the form of discounts, concessionssome or commissions. Subject to certain conditions, the underwriters will be obligated to purchase all of the securities offeredshares of Series A Convertible Preferred Stock, Series A Warrants, Series B Warrants or shares of common stock owned by them and, if they default in the prospectus supplement. Weperformance of their secured obligations, the pledgees or secured parties may changeoffer and sell the shares of common stock from time to time the public offering price and any discounts or concessions allowed or reallowed or paidpursuant to dealers.

The selling stockholders and any broker-dealer participating in the distribution of the securities offered hereby may be deemed to be “underwriters” within the meaning of the Securities Act, and any commission paid, or any discounts and commissions received by them andor concessions allowed to, any profit realized by them on resale of the securitiessuch broker-dealer may be deemed to be underwriting commissions or discounts under the Securities Act. At the time a particular offering of the securities is made, a prospectus supplement, if required, will be distributed which will set forth the aggregate amount and type of securities being offered and the terms of the offering, including the name or names of any broker-dealers or agents, any discounts, commissions and other terms constituting compensation from the selling stockholders and any discounts, commissions or concessions allowed or reflowed or paid to broker-dealers.

Under the securities laws of some states, the securities offered hereby may be sold in such states only through registered or licensed brokers or dealers. In addition, in some states the securities offered hereby may not be sold unless such shares have been registered or qualified for sale in such state or an exemption from registration or qualification is available and is complied with.

There can be no assurance that we and/or any selling stockholder will sell any or all of the securities registered pursuant to the registration statement, of which this prospectus forms a part.

The selling stockholders and any other person participating in such distribution will be subject to applicable provisions of the Securities Exchange Act of 1934, as amended, and the rules and regulations thereunder, including, without limitation, Regulation M of the Exchange Act, which may limit the timing of purchases and sales of any of the securities by the selling stockholders and any other participating person. Regulation M may also restrict the ability of any person engaged in the distribution of the securities to engage in market-making activities with respect to the securities. All of the foregoing may affect the marketability of the securities and the ability of any person or entity to engage in market-making activities with respect to the securities.

We will pay all expenses of the registration of the shares of common stock pursuant to the Rights Agreement, including, without limitation, SEC filing fees and expenses of compliance with state securities or “blue sky” laws; provided, however, that a selling stockholder will pay all underwriting discounts and commissions.selling commissions, if any. We will indemnify the selling stockholders against liabilities, including some liabilities under the Securities Act, in accordance with the Rights Agreement, or the selling stockholders will be entitled to contribution. We may enter into agreements to indemnify underwriters, dealers and agentsbe indemnified by the selling stockholders against civil liabilities, including liabilities under the Securities Act, that may arise from any written information furnished to us by the selling stockholder specifically for use in this prospectus, in accordance with the related Rights Agreement, or we may be entitled to contributecontribution.

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

THE SECURITIES WE MAY OFFER

We may offer and sell, from time to payments theytime, in one or more offerings, any combination of common stock, preferred stock, convertible or non-convertible debt securities, warrants, rights and/or units having an aggregate initial offering price not to exceed $100,000,000. The preferred stock may be convertible into shares of our common stock, shares of our preferred stock, debt securities, warrants, rights and/or units. The debt securities may be convertible into or exchangeable for shares of our common stock, shares of our preferred stock, other debt securities, warrants, rights and/or units, or may be non-convertible. The warrants may be exercisable for shares of common stock, shares of preferred stock, debt securities and/or units. The rights may be exercisable for shares of common stock, shares of preferred stock, debt securities, warrants and/or units. The units may consist of any combination of the other types of securities described in this prospectus, which may or may not be separable from one another.

This prospectus also relates to the offer and resale of up to an aggregate of 148,965,762 shares of our common stock held by the selling stockholders identified in this prospectus in the section entitled “Selling Stockholders”. The selling stockholders may sell any, all or none of the securities offered by this prospectus, and we do not know when or in what amount the selling stockholders may sell their shares of common stock hereunder. We will not receive any proceeds from the sale of shares of our common stock by the selling stockholders All of the shares of common stock offered by the selling stockholders pursuant to this prospectus will be sold by the selling stockholders for their own account.

This prospectus provides a general description of the securities we and the selling stockholders may offer and sell from time to time. Each time we offer and sell any of our securities under this prospectus, we will, to the extent required by law, provide a prospectus supplement that will contain specific information about the terms of the offering. To the extent that any selling stockholder resells any securities, the selling stockholder may be required to makeprovide you with a prospectus supplement containing specific information about the selling stockholder and the terms of the offering. The prospectus supplement may also add, update or change information in respect thereof.

We or the selling stockholders may sell the securities to or through underwriters, dealers or agents or directly to purchasers or as otherwise described in connectionthe section entitled “Plan of Distribution.” Each prospectus supplement will set forth the names of any underwriters, dealers, agents or other entities involved in the sale of securities described in that prospectus supplement and any applicable fee, commission or discount arrangements with suchthem.

DESCRIPTION OF CAPITAL STOCK

The following is a transaction,summary of all material characteristics of our capital stock as set forth in our Amended and Restated Certificate of Incorporation, as amended, or our Charter, our Second Amended and Restated Bylaws, as amended, or our Bylaws, and the third partiesAmended Certificate of Designations. The summary does not purport to be complete and is qualified in its entirety by reference to our Charter, our Bylaws and the Amended Certificate of Designations, copies of which have been filed as exhibits to our public filings with the SEC. See the section entitled “Exhibit Index” for additional information.

Common Stock

General. We may issue shares of our common stock from time to time. We are authorized to issue 300,000,000 shares of common stock, par value $0.001 per share. As of November 2, 2020, there were 49,279,453 shares of our common stock issued and outstanding.

Dividend Rights. Subject to preferences that may apply to any shares of preferred stock outstanding at the time, the holders of outstanding shares of our common stock are entitled to receive dividends out of funds legally available at the times and in the amounts that our board of directors may determine.

Voting Rights. Holders of our common stock are entitled to one vote for each share held on all matters submitted to a vote at a meeting of stockholders and do not have cumulative voting rights.

No Preemptive or Similar Rights. Our common stock is not entitled to preemptive rights, and is not subject to redemption. There are no sinking fund provisions applicable to our common stock.

Conversion. Our common stock is not convertible into any other shares of our capital stock.

Right to Receive Liquidation Distributions. Upon our liquidation, dissolution or winding-up, the assets legally available for distribution to our stockholders would be distributable ratably among the holders of our common stock after payment of liquidation preferences, if any, on any outstanding shares of preferred stock and payment of claims of creditors.

Preferred Stock

Pursuant to the terms of our Charter, our board of directors is authorized, subject to limitations prescribed by Delaware law, to issue up to 10,000,000 shares of preferred stock, par value $0.001 per share, in one or more series, to establish from time to time the number of shares to be included in each series, and to fix the designation, powers, preferences and rights of the shares of each series and any of its qualifications, limitations or restrictions, in each case without further action by our stockholders.

On November 18, 2019, we filed the Certificate of Designations, Preferences, and Rights of Series A Convertible Preferred Stock with the Secretary of State of the State of Delaware and, on January 7, 2020, we filed the Amended Certificate of Designations with the Secretary of State of the State of Delaware, establishing the rights, preferences, privileges, qualifications, restrictions and limitations relating to 350,000 shares of our Series A Convertible Preferred Stock, par value $0.001 per share. Our Series A Convertible Preferred Stock rank senior to our common stock with respect to rights as to dividends, distributions, redemptions and payments upon the liquidation, dissolution and winding up of Acacia. Holders of our Series A Convertible Preferred Stock have the right to vote with holders of our common stock on an as-converted basis on all matters.

Whenever preferred stock is to be offered and sold pursuant to this prospectus, we will file a prospectus supplement relating to that offer and sale which will specify (in each case to the extent applicable):

The DGCL provides that the holders of preferred stock will have the right to vote separately as a class on any proposed fundamental change in the rights of the preferred stock. This right is in addition to any voting rights that may be provided for in the applicable prospectus supplement, sell securities coveredcertificate of designation.

All shares of preferred stock offered by this prospectus will, when issued, be fully paid and nonassessable and will not have any preemptive or similar rights.

Delaware Law and Certain Charter and Bylaw Provisions

The provisions of Delaware law, as well as certain terms of our Charter and Bylaws, may have the effect of delaying, deferring or discouraging another person from acquiring control of us by means of a tender offer, a proxy contest or otherwise, or removing incumbent officers and directors. These provisions, some of which are summarized below, are expected to discourage certain types of coercive takeover practices and takeover bids that our board of directors may consider inadequate and to encourage any person seeking to acquire control of us to first negotiate with our board of directors.

Delaware Law. We are governed by the provisions of Section 203 of the DGCL. In general, Section 203 prohibits a public Delaware corporation from engaging in a “business combination” with an “interested stockholder” for a period of three years after the date such stockholder became an “interested stockholder.” A “business combination” includes mergers, asset sales or other transactions resulting in a financial benefit to the stockholder. An “interested stockholder” is a person who, together with affiliates and associates, owns, or within three years did, prior to the determination of interested stockholder status, own, 15% or more of the corporation’s outstanding voting stock.

Charter and Bylaw Provisions. Each of our Charter and Bylaws include a number of other provisions that may have the effect of deterring hostile takeovers or delaying or preventing changes in control or our management, including the following:

Registration Rights Agreement

Our Rights Agreement with Starboard Value and the applicable prospectus supplement. If so,Buyers provides that we will, among other things, prepare and file with the third party maySEC (i) the Initial Registration Statement covering the resale of the Underlying Shares, and (ii) subsequent registration statements covering the resale of Underlying Shares to the extent not included in previous registration statements. In addition, upon written notice to us by Starboard Value, or a Demand Notice, we will prepare and file with the SEC a registration statement covering the resale of any Series A Convertible Preferred Stock, Notes and/or Series B Warrants set forth in such Demand Notice.

At any time beginning on November 18, 2020, upon Starboard Value’s request, we will use securities borrowed from us our reasonable best efforts to cause the Series A Convertible Preferred Stock, Series B Warrants and/or othersthe Notes to settle such sales and may use securities received from us to close outbe, as requested by Starboard Value, listed for trading on The Nasdaq Global Select Market or any related short positions. We may also loan or pledge securities coveredother eligible market as selected by us.

The registration statement of which this prospectus is a part has been filed by us in satisfaction of our obligations under the Purchase Agreement and the applicable prospectus supplementRights Agreement to third parties, who may sellfile the loaned securities or, in an eventInitial Registration Statement. We intend to maintain the effectiveness of default in the caseregistration statement until the earlier of a pledge, sell(i) such time as the pledged securitiesshares offered by the selling stockholders pursuant to this prospectus andhave been sold, or (iii) such time as such shares offered by the applicable prospectus supplement. The third party in such sale transactions will be an underwriter and will be identified in the applicable prospectus supplement.

We have certain customary obligations under the Rights Agreement to indemnify for losses incurred by the initial selling stockholder in connection with any applicableuntrue statements of material fact or material omissions in the registration statement of which this prospectus supplement.is a part and for certain violations of securities and other similar laws.

Governance Agreement

Board Appointments and Related Agreements. On November 18, 2019, pursuant to our Governance Agreement with Starboard, we (i) increased the size of our Board of Directors from six to seven members, (ii) appointed Jonathan Sagal as the Starboard Appointee, (iii) granted Starboard the right to recommend two Additional Appointees, (iv) formed the Strategic Committee, which was tasked with, among other things, sourcing and performing due diligence on potential acquisition targets and intellectual property or other investment opportunities, with the goal of finding one or more Approved Investments, (v) appointed Clifford Press, Alfred V. Tobia, Jr. and Jonathan Sagal to the Strategic Committee, with Clifford Press serving as its Chairman, and (vi) appointed Jonathan Sagal to the Nominating and Corporate Governance Committee of the Board of Directors.

The underwriters, dealersGovernance Agreement provides that during the period beginning on November 18, 2019 and agentsending on the earlier of (i) fifteen (15) days prior to the deadline for the submission of stockholder nominations for our 2020 annual meeting of stockholders pursuant to our Second Amended and Restated Bylaws, or (ii) April 6, 2020 (such period, as may engagebe extended by Starboard under certain circumstances, the Governance Period), the Board will remain at no more than seven directors, provided that the Board may be increased during the period to (a) accommodate the appointment of the Additional Appointees, (b) upon Starboard’s written consent, or (c) if our stockholders take actions to increase the size of the Board.

During the Governance Period, one or more Starboard partners or senior employees, or the Starboard Observers, will have the right to attend and participate in meetings of the Strategic Committee and will receive copies of all documents distributed to the Strategic Committee. The Starboard Observers may attend and participate, but not vote, at all meetings of the Strategic Committee during the Governance Period.

If there is a vacancy on the Board during the Governance Period as a result of any of the Starboard Appointee or the Additional Appointees no longer serving on the Board for any reason, then Starboard will be entitled to designate a replacement thereof, or a Replacement Director; provided that at such time certain criteria set forth in the Governance Agreement are satisfied, including that Starboard beneficially own, in the aggregate, at least 4.0% of our then-outstanding common stock (on an as-converted basis, if applicable).

Governance Provisions. The Governance Agreement provides that during the Governance Period, Starboard has agreed not to take certain actions with respect to us, including but not limited to (i) engaging in any solicitation of proxies or consents with respect to our securities, (ii) forming or joining a “group” (within the meaning of Section 13(d)(3) of the Securities Exchange Act of 1934), with respect to our capital stock, (iii), depositing any of our securities in any voting trust, (iv) seeking or submitting nominations in furtherance of a contested solicitation for the appointment, election or removal of our directors, (v) making any proposal for consideration by stockholders at any annual or special meeting of stockholders or through any action by written consent, or taking certain actions with respect to any merger, takeover, tender offer, acquisition, recapitalization, restructuring, disposition or other transactionsbusiness combination involving us, (vi) seeking representation on the Board or removal of any member of the Board, except as permitted in the Governance Agreement, (vii) advising, encouraging, supporting or influencing any person or entity with respect to the voting or disposition of our securities at any annual or special meeting of stockholders or in connection with any consent solicitation with respect to the appointment, election or removal of directors, except as permitted in the Governance Agreement, or (viii) making any request or submitting any proposal to amend the terms of the Governance Agreement other than through non-public communications with us or perform other servicesthe Board that would not be reasonably determined to trigger public disclosure obligations for us or for Starboard.

Tax Benefits Preservation Plan

Under the terms of our Tax Benefits Preservation Plan, in general, if a person or group acquires beneficial ownership of 4.9% or more of the ordinary courseoutstanding shares of their business. Weour common stock without prior approval of our board of directors or without meeting certain exceptions, the rights would become exercisable and our stockholders (other than the acquiring person) will describehave the right to purchase securities from us at a discount to such relationshipssecurities’ fair market value, thus causing substantial dilution to the acquiring person. As a result, the Tax Benefits Preservation Plan may have the effect of inhibiting or impeding a change in control not approved by our board of directors.

Nasdaq Global Select Market

Our common stock is listed on NASDAQ and traded under the prospectus supplement namingsymbol “ACTG.” On November 6, 2020, the underwriterlast reported sale price for our common stock on NASDAQ was $3.59 per share.

Transfer Agent and the natureRegistrar

The transfer agent and registrar for our shares of any such relationship.common stock is Computershare Trust Company, N.A.

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DESCRIPTION OF WARRANTS

The following description, together with the additional information we may include in any applicable prospectus supplements and free writing prospectuses, summarizes the material terms and provisions of the warrants that weDEBT SECURITIES

We may offer under this prospectus, which consist of warrantsand sell, from time to purchase common stock. Warrantstime, in one or more series, debt securities that may be issued independently, together with any otheras senior or subordinated convertible debt securities, offered by any prospectus supplement or through a dividendas senior or other distribution to our stockholders and may be attached to or separate from the relatedsubordinated non-convertible debt securities. The following sets forth certain general terms and provisions of the warrants that may be offered under this prospectus. While the terms we have summarized below will apply generally to any warrantsdebt securities that we may offer under this prospectus, we will describe the particular terms of any series of warrantsdebt securities that we may offer in more detail in the applicable prospectus supplement and any applicable free writing prospectus.supplement. The terms of any warrantsdebt securities offered under a prospectus supplement may differ from the terms described below. However, no prospectus supplement will fundamentally changeUnless the termscontext requires otherwise, whenever we refer to the indenture, we are also referring to any supplemental indentures that are set forth in this prospectus or offer a security that is not registered and described in this prospectus atspecify the time of its effectiveness.

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Warrants may be issued under a warrant agreement to be entered into between us and a warrant agent specified in the applicable prospectus supplement. The warrant agent will act solely as our agent in connection with the warrantsterms of a particular series andof debt securities.

We will not assume any obligationissue the debt securities under the indenture that we will enter into with the trustee named in the indenture. The indenture will be qualified under the Trust Indenture Act of 1939, as amended, or relationship of agency or trust for or with any holders or beneficial owners of warrants. The applicable warrant agreement andthe Trust Indenture Act. We have filed the form of warrant certificate will be filedindenture as exhibitsan exhibit to or incorporated by reference in the registration statement of which this prospectus is a part. Furtherpart, and supplemental indentures and forms of debt securities containing the terms of the warrantsdebt securities being offered and sold will be filed as exhibits to the registration statement of which this prospectus is a part and/or will be incorporated by reference from reports that we file with the SEC.

The following summary of material provisions of the debt securities and the indenture is subject to, and qualified in its entirety by reference to, all of the provisions of the indenture applicable warrantto a particular series of debt securities. We urge you to read the applicable prospectus supplements related to the debt securities that we may offer and sell under this prospectus, as well as the complete indenture that contains the terms of the debt securities.

General

The indenture does not limit the amount of debt securities that we may issue. It provides that we may issue debt securities up to the principal amount that we may authorize and may be in any currency or currency unit that we may designate. The terms of the indenture do not contain any covenants or other provisions designed to give holders of any debt securities protection against changes in our operations, financial condition or transactions.

We may issue the debt securities issued under the indenture as “discount securities,” which means they may be sold at a discount to their stated principal amount. These debt securities, as well as other debt securities that are not issued at a discount, may be issued with “original issue discount,” or OID, for U.S. federal income tax purposes because of interest payment and other characteristics or terms of the debt securities. Material U.S. federal income tax considerations applicable to debt securities issued with OID will be described in more detail in any applicable prospectus supplement.

Whenever debt securities are to be issued and sold pursuant to this prospectus, we will file a prospectus supplement relating to that offer and sale which will specify (in each case to the extent applicable):

	·	the title of the series of debt securities;
	·	any limit upon the aggregate principal amount that may be issued;
	·	the maturity date or dates;
	·	the form of the debt securities of the series;
	·	the applicability of any guarantees;
	·	whether or not the debt securities will be secured or unsecured, and the terms of any secured debt;
	·	whether the debt securities rank as senior debt, senior subordinated debt, subordinated debt or any combination thereof, and the terms of any subordination;

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	·	if the price at which such debt securities will be issued is a price other than the principal amount thereof, the portion of the principal amount thereof payable upon declaration of acceleration of the maturity thereof, or if applicable, the portion of the principal amount of such debt securities that is convertible into another security or the method by which any such portion shall be determined;
	·	the interest rate or rates, which may be fixed or variable, or the method for determining the rate and the date interest will begin to accrue, the dates interest will be payable and the regular record dates for interest payment dates or the method for determining such dates;
	·	our right, if any, to defer payment of interest and the maximum length of any such deferral period;
	·	if applicable, the date or dates after which, or the period or periods during which, and the price or prices at which, we may, at our option, redeem the series of debt securities pursuant to any optional or provisional redemption provisions and the terms of those redemption provisions;
	·	the date or dates, if any, on which, and the price or prices at which we are obligated, pursuant to any mandatory sinking fund or analogous fund provisions or otherwise, to redeem, or at the holder’s option to purchase, the series of debt securities and the currency or currency unit in which the debt securities are payable;
	·	the denominations in which we will issue the series of debt securities;
	·	any and all terms, if applicable, relating to any auction or remarketing of the debt securities of that series and any security for our obligations with respect to such debt securities and any other terms which may be advisable in connection with the marketing of the debt securities of that series;
	·	whether the debt securities of the series shall be issued in whole or in part in the form of a global security or securities; the terms and conditions, if any, upon which such global security or securities may be exchanged in whole or in part for other individual securities; and the depositary for such global security or securities;
	·	if applicable, the provisions relating to conversion or exchange of any debt securities of the series, and the terms and conditions upon which such debt securities will be so convertible or exchangeable, including the conversion or exchange price, as applicable, or how it will be calculated and may be adjusted, any mandatory or optional conversion or exchange features, the applicable conversion or exchange period and the manner of settlement for any conversion or exchange;
	·	if other than the full principal amount thereof, the portion of the principal amount of debt securities of the series which shall be payable upon declaration of acceleration of the maturity thereof;
	·	additions to or changes in the covenants applicable to the particular debt securities being issued, including, among others, the consolidation, merger or sale covenant;
	·	additions to or changes in the events of default with respect to the securities and any change in the right of the trustee or the holders to declare the principal, premium, if any, and interest, if any, with respect to such securities to be due and payable;
	·	additions to or changes in or deletions of the provisions relating to covenant defeasance and legal defeasance;
	·	additions to or changes in the provisions relating to satisfaction and discharge of the indenture;
	·	additions to or changes in the provisions relating to the modification of the indenture both with and without the consent of holders of debt securities issued under the indenture;

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	·	the currency of payment of the debt securities if other than U.S. dollars and the manner of determining the equivalent amount in U.S. dollars;
	·	whether interest will be payable in cash or additional debt securities at our or the holders’ option and the terms and conditions upon which the election may be made;
	·	the terms and conditions, if any, upon which we shall pay amounts in addition to the stated interest premium, if any, and principal amounts of the debt securities of the series to any holder that is not a “United States person” for federal tax purposes;
	·	any restrictions on transfer, sale or assignment of the debt securities of the series; and
	·	any other specific terms, preferences, rights or limitations of, or restrictions on, the debt securities, any other additions or changes in the provisions of the indenture, and any terms that may be required by us or advisable under applicable laws or regulations.

Conversion or Exchange Rights

We will set forth in the applicable prospectus supplement the terms on which a series of debt securities may be convertible into or exchangeable for our common stock, our preferred stock or our other debt securities. We will include provisions as to settlement upon conversion or exchange and whether conversion or exchange is mandatory, at the option of the holder or at our option. We may include provisions pursuant to which the number of shares of our common stock, our preferred stock or our other debt securities that the holders of the series of debt securities receive would be subject to adjustment.

Consolidation, Merger or Sale

Unless we provide otherwise in the prospectus supplement applicable to a particular series of debt securities, the indenture will not contain any covenant that restricts our ability to merge or consolidate, or sell, convey, transfer or otherwise dispose of all or substantially all of our assets.

Events of Default under the Indenture

Unless we provide otherwise in the prospectus supplement applicable to a particular series of debt securities, the following are events of default under the indenture with respect to any series of debt securities that we may issue:

	·	if we fail to pay any installment of interest on any series of debt securities, as and when the same shall become due and payable, and such default continues for a period of 90 days; provided, however, that a valid extension of an interest payment period by us in accordance with the terms of any indenture supplemental thereto shall not constitute a default in the payment of interest for this purpose;
	·	if we fail to pay the principal of, or premium, if any, on any series of debt securities as and when the same shall become due and payable whether at maturity, upon redemption, by declaration or otherwise, or in any payment required by any sinking or analogous fund established with respect to such series; provided, however, that a valid extension of the maturity of such debt securities in accordance with the terms of any indenture supplemental thereto shall not constitute a default in the payment of principal or premium, if any;
	·	if we fail to observe or perform any other covenant or agreement contained in the debt securities or the indenture, other than a covenant specifically relating to another series of debt securities, and our failure continues for 90 days after we receive written notice of such failure, requiring the same to be remedied and stating that such is a notice of default thereunder, from the trustee or holders of at least 25% in aggregate principal amount of the outstanding debt securities of the applicable series; and
	·	if specified events of bankruptcy, insolvency or reorganization occur.

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If an event of default with respect to debt securities of any series occurs and is continuing, other than an event of default specified in the last bullet point above, the trustee or the holders of at least 25% in aggregate principal amount of the outstanding debt securities of that series, by notice to us in writing, and to the trustee if notice is given by such holders, may declare the unpaid principal of, premium, if any, and accrued interest, if any, due and payable immediately. If an event of default specified in the last bullet point above occurs with respect to us, the principal amount of and accrued interest, if any, of each issue of debt securities then outstanding shall be due and payable without any notice or other action on the part of the trustee or any holder.

The holders of a majority in principal amount of the outstanding debt securities of an affected series may waive any default or event of default with respect to the series and its consequences, except defaults or events of default regarding payment of principal, premium, if any, or interest, unless we have cured the default or event of default in accordance with the indenture. Any waiver shall cure the default or event of default.

Subject to the terms of the indenture, the trustee will be under no obligation to exercise any of its rights or powers under such indenture at the request or direction of any of the holders of the applicable series of debt securities, unless such holders have offered the trustee reasonable indemnity; provided that if an event of default under an indenture shall occur and be continuing, the trustee shall be required to exercise with respect to debt securities of that series such of the rights and powers vested in the trustee by the applicable indenture and to use the same degree of care as a prudent person would exercise or use in the conduct of his or her own affairs. The holders of a majority in principal amount of the outstanding debt securities of any series will have the right to direct the time, method and place of conducting any proceeding for any remedy available to the trustee, or exercising any trust or power conferred on the trustee, with respect to the debt securities of that series, provided that:

	·	the direction so given by the holder is not in conflict with any law or the applicable indenture; and
	·	subject to its duties under the Trust Indenture Act, the trustee need not take any action that might involve it in personal liability or might be unduly prejudicial to the holders not involved in the proceeding.
	·	A holder of the debt securities of any series will have the right to institute a proceeding under the indenture or to appoint a receiver or trustee, or to seek other remedies only if:
	·	the holder has given written notice to the trustee of a continuing event of default with respect to that series;
	·	the holders of at least 25% in aggregate principal amount of the outstanding debt securities of that series have made written request, and such holders have offered to the trustee indemnity satisfactory to it against the costs, expenses and liabilities to be incurred by the trustee in compliance with the request; and
	·	the trustee does not institute the proceeding, and does not receive from the holders of a majority in aggregate principal amount of the outstanding debt securities of that series other conflicting directions within 90 days after the notice, request and offer.

We will periodically file statements with the trustee regarding our compliance with specified covenants in the indenture.

Modification of Indenture; Waiver

We and the trustee may change an indenture without the consent of any holders with respect to specific matters:

	·	to cure any ambiguity, defect or inconsistency in the indenture or in the debt securities of any series;
	·	to provide for uncertificated debt securities in addition to or in place of certificated debt securities;
	·	to add to our covenants, restrictions, conditions or provisions such new covenants, restrictions, conditions or provisions for the benefit of the holders of all or any series of debt securities, to make the occurrence, or the occurrence and the continuance, of a default in any such additional covenants, restrictions, conditions or provisions an event of default or to surrender any right or power conferred upon us in the indenture;

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	·	to add to, delete from or revise the conditions, limitations, and restrictions on the authorized amount, terms, or purposes of issue, authentication and delivery of debt securities, as set forth in the indenture;
	·	to make any change that does not adversely affect the interests of any holder of debt securities of any series in any material respect;
	·	to provide for the issuance of and establish the form and terms and conditions of the debt securities of any series as provided above under “Description of Debt Securities—General” to establish the form of any certifications required to be furnished pursuant to the terms of the indenture or any series of debt securities, or to add to the rights of the holders of any series of debt securities;
	·	to evidence and provide for the acceptance of appointment under any indenture by a successor trustee; or
	·	to comply with any requirements of the SEC in connection with the qualification of any indenture under the Trust Indenture Act.

In addition, under the indenture, the rights of holders of a series of debt securities may be changed by us and the trustee with the written consent of the holders of at least a majority in aggregate principal amount of the outstanding debt securities of each series that is affected. However, unless we provide otherwise in the prospectus supplement applicable to a particular series of debt securities, we and the trustee may make the following changes only with the consent of each holder of any outstanding debt securities affected:

	·	extending the fixed maturity of any debt securities of any series;
	·	reducing the principal amount, reducing the rate of or extending the time of payment of interest, or reducing any premium payable upon the redemption of any series of any debt securities; or
	·	reducing the percentage of debt securities, the holders of which are required to consent to any amendment, supplement, modification or waiver.

Discharge

The indenture provides that we can elect to be discharged from our obligations with respect to one or more series of debt securities, other than certain specified obligations, which include obligations to:

	·	provide for payment;
	·	register the transfer or exchange of debt securities of the series;
	·	replace stolen, lost or mutilated debt securities of the series;
	·	pay principal of and premium and interest on any debt securities of the series;
	·	maintain paying agencies;
	·	hold monies for payment in trust;
	·	recover excess money held by the trustee;
	·	compensate and indemnify the trustee; and
	·	appoint any successor trustee.

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In order to exercise our rights to be discharged, we must deposit with the trustee money or government obligations sufficient to pay all the principal of, any premium, if any, and interest on, the debt securities of the series on the dates payments are due.

Form, Exchange and Transfer

We will issue the debt securities of each series only in fully registered form without coupons and, unless we provide otherwise in the applicable prospectus supplement, in denominations of $1,000 and any integral multiple thereof. The indenture provides that we may issue debt securities of a series in temporary or permanent global form and as book-entry securities that will be deposited with, or on behalf of, The Depository Trust Company, or DTC, or another depositary named by us and identified in the applicable prospectus supplement with respect to that series. To the extent the debt securities of a series are issued in global form and as book-entry, a description of terms relating to any book entry securities will be set forth in the applicable prospectus supplement.

At the option of the holder, subject to the terms of the indenture and the limitations applicable to global securities described in the applicable prospectus supplement, the holder of the debt securities of any series can exchange the debt securities for other debt securities of the same series, in any authorized denomination and of like tenor and aggregate principal amount.

Subject to the terms of the indenture and the limitations applicable to global securities set forth in the applicable prospectus supplement, holders of the debt securities may present the debt securities for exchange or for registration of transfer, duly endorsed or with the form of transfer endorsed thereon duly executed if so required by us or the security registrar, at the office of the security registrar or at the office of any transfer agent designated by us for this purpose. Unless otherwise provided in the debt securities that the holder presents for transfer or exchange, we will impose no service charge for any registration of transfer or exchange, but we may require payment of any taxes or other governmental charges.

We will name in the applicable prospectus supplement the security registrar, and any transfer agent in addition to the security registrar, that we initially designate for any debt securities. We may at any time designate additional transfer agents or rescind the designation of any transfer agent or approve a change in the office through which any transfer agent acts, except that we will be required to maintain a transfer agent in each place of payment for the debt securities of each series.

If we elect to redeem the debt securities of any series, we will not be required to:

	·	issue, register the transfer of, or exchange any debt securities of that series during a period beginning at the opening of business 15 days before the day of mailing of a notice of redemption of any debt securities that may be selected for redemption and ending at the close of business on the day of the mailing; or
	·	register the transfer of or exchange any debt securities so selected for redemption, in whole or in part, except the unredeemed portion of any debt securities we are redeeming in part.

Information Concerning the Trustee

The trustee, other than during the occurrence and continuance of an event of default under an indenture, undertakes to perform only those duties as are specifically set forth in the applicable free writing prospectus.indenture. Upon an event of default under an indenture, the trustee must use the same degree of care as a prudent person would exercise or use in the conduct of his or her own affairs. Subject to this provision, the trustee is under no obligation to exercise any of the powers given it by the indenture at the request of any holder of debt securities unless it is offered reasonable security and indemnity against the costs, expenses and liabilities that it might incur.

Payment and Paying Agents

Unless we otherwise indicate in the applicable prospectus supplement, we will make payment of the interest on any debt securities on any interest payment date to the person in whose name the debt securities, or one or more predecessor securities, are registered at the close of business on the regular record date for the interest.

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We will pay principal of and any premium and interest on the debt securities of a particular series at the office of the paying agents designated by us, except that unless we otherwise indicate in the applicable prospectus supplement, we will make interest payments by check that we will mail to the holder or by wire transfer to certain holders. Unless we otherwise indicate in the applicable prospectus supplement, we will designate the corporate trust office of the trustee as our sole paying agent for payments with respect to debt securities of each series. We will name in the applicable prospectus supplement any other paying agents that we initially designate for the debt securities of a particular series. We will maintain a paying agent in each place of payment for the debt securities of a particular series.

All money we pay to a paying agent or the trustee for the payment of the principal of or any premium or interest on any debt securities that remains unclaimed at the end of two years after such principal, premium or interest has become due and payable will be repaid to us, and the holder of the debt security thereafter may look only to us for payment thereof.

Governing Law

The indenture and the debt securities will be governed by and construed in accordance with the internal laws of the State of New York, except to the extent that the Trust Indenture Act of 1939 is applicable.

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DESCRIPTION OF WARRANTS

We may offer and sell, from time to time, warrants to purchase shares of common stock, shares of preferred stock, debt securities and/or units. If we issue warrants, they will be evidenced by warrant agreements or warrant certificates issued under one or more warrant agreements, which will be contracts between us and the holders of the warrants or an agent for the holders of the warrants. The forms of warrant agreements or warrant certificates, as applicable, relating to the warrants will be filed as exhibits to the registration statement of which this prospectus is a part and/or will be incorporated by reference from reports that we file with the SEC.

The following summary of material provisions of the warrants and warrant agreements are subject to, and qualified in their entirety by reference to, all of the provisions of the warrant agreements and warrant certificates applicable to a particular series of warrants. We urge you to read the applicable prospectus supplement, and any applicable free writing prospectus related to the particular series of warrants that we sell under this prospectus, as well as the complete warrant agreements and warrant certificates that contain the terms of the warrants.

The applicableany warrants we may issue.

Whenever warrants are to be issued and sold pursuant to this prospectus, we will file a prospectus supplement relating to that offer and sale which will describe the terms of the warrants in respect of which this prospectus is being delivered, including, where applicable, the following:

specify (in each case as applicable):

Ÿ

·

the title of the warrants;

Ÿ	the aggregate number of shares of common stock or preferred stock purchasable upon the exercise of warrants, offered;

Ÿ	and the price or prices at which the warrants willsuch shares may be issued;purchased upon such exercise;

Ÿ
	·	the designation, numberstated value and other terms of the sharesany series of our commonpreferred stock purchasable upon exercise of thesuch warrants;

Ÿ
	·	the designationdebt securities purchasable upon the exercise of warrants, and the price at which such debt securities may be purchased upon such exercise;
	·	the principal amount, seniority and other terms of the otherany debt securities if any, with which the warrants are issued and purchasable upon exercise of such warrants;
	·	the number of units, and the securities comprising such units, purchasable upon the exercise of warrants, issued with each security;and the price at which such units may be purchased upon such exercise;

Ÿ
	·	the date, if any, on and after which the warrants and the related common stock, preferred stock, debt securities and/or other securities, if any,units will be separately transferable;

Ÿ
	·	the price at which each shareterms of common stock purchasable upon exercise ofany rights to redeem or call the warrants may be purchased;warrants;

Ÿ
	·	the date on which the right to exercise the warrants will commence and the date on which thatthe right will expire;

Ÿ	the minimum or maximum amount of the warrants which may be exercised at any one time;

Ÿ	information with respect to book-entry procedures, if any;

Ÿ	a discussion of federal income tax considerations; and

Ÿ
	·	any otheradditional terms of the warrants, including terms, procedures and limitations relating to the transferability,exchange, exercise and settlement of the warrants.

Each warrant will entitle its holder to purchase the number of shares of common stock or preferred stock, the principal amount of debt securities, or the number of units, at the exercise price set forth in (or calculable as set forth in) the applicable prospectus supplement and warrant agreement. Unless we otherwise specify in the applicable prospectus supplement, holders of the warrants may exercise the warrants at any time up to the specified time on the expiration date that we set forth in the applicable prospectus supplement and warrant agreement.

A holder of warrant certificates may exchange them for new warrant certificates of different denominations, present them for registration of transfer, and exercise them as indicated in the applicable prospectus supplement and warrant agreement. Until any warrants to purchase common stock or preferred stock are exercised, the holders of the warrants will not have any rights of holders of the underlying common stock or preferred stock, including any voting rights or any rights to receive dividends or payments upon any liquidation, dissolution or winding up on the common stock or preferred stock, if any. Until any warrants to purchase debt securities are exercised, the holder of the warrants will not have any rights of holders of the debt securities that can be purchased upon exercise, including any rights to receive payments of principal, premium or interest on the underlying debt securities or to enforce covenants in the applicable indenture. Until any warrants to purchase units are exercised, the holder of the warrants will not have any rights of holders of the units, or the securities comprising such units, that can be purchased upon exercise.

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DESCRIPTION OF RIGHTS

We may issue, from time to time, rights to our stockholders to purchase shares of common stock, shares of preferred stock, debt securities, warrants and/or units.  If we issue rights, they will be issued under a separate rights agreement to be entered into between us and a bank or trust company, as rights agent. The rights agent will act solely as our agent in connection with the certificates relating to the rights and will not assume any obligation or relationship of agency or trust for or with any holders of rights certificates or beneficial owners of rights.  The forms of rights agreement and rights certificate, as applicable, relating to the rights will be filed as exhibits to the registration statement of which this prospectus is a part and/or will be incorporated by reference from reports that we file with the SEC.

The following summary of material provisions of the rights agreements and rights certificates are subject to, and qualified in their entirety by reference to, all of the provisions of the rights agreements and rights certificates applicable to a particular issuance of rights. We urge you to read the applicable prospectus supplement, as well as the complete rights agreements and rights certificates that contain the terms of any rights we may issue.

Whenever rights are to be issued pursuant to this prospectus, we will file a prospectus supplement relating to that issuance which will specify (in each case as applicable):

	·	the record date for determining the stockholders entitled to the rights distribution;
	·	the number of shares of common stock or preferred stock purchasable upon the exercise of rights, and the price at which such number of shares may be purchased upon such exercise;
	·	the designation, stated value and other terms of any series of preferred stock purchasable upon exercise of such rights;
	·	the debt securities purchasable upon the exercise of rights, and the price at which such debt securities may be purchased upon such exercise;
	·	the principal amount, seniority and other terms of the debt securities purchasable upon exercise of rights;
	·	the number of warrants, and the securities underlying such warrants, purchasable upon the exercise of rights, and the price at which such number of warrants may be purchased upon such exercise;
	·	the number of units, and the securities comprising such units, purchasable upon the exercise of such rights, and the price at which such number of units may be purchased upon such exercise;
	·	the aggregate number of rights being issued;
	·	the date, if any, on and after which the rights and the related common stock, preferred stock, debt securities, warrants and/or units will be separately transferable;
	·	the date on which the right to exercise such rights shall commence, and the date on which such right shall expire; and
	·	any other terms of such rights, including procedures and limitations relating to the distribution, exchange and exercise of the warrants.such rights.

Each rights certificate will entitle its holder to purchase the number of shares of common stock or preferred stock, the principal amount of debt securities, the number of warrants and/or the number of units, at the exercise price set forth in (or calculable as set forth in) the applicable prospectus supplement and rights agreement. Unless we otherwise specify in the applicable prospectus supplement, holders of the rights may exercise the rights at any time up to the specified time on the expiration date that we set forth in the applicable prospectus supplement and rights agreement.

Until any rights to purchase common stock or preferred stock are exercised, the holders of the rights will not have any rights of holders of the underlying common stock or preferred stock, including any voting rights or any rights to receive dividends or payments upon any liquidation, dissolution or winding up on the common stock or preferred stock, if any. Until any rights to purchase debt securities are exercised, the holder of the rights will not have any rights of holders of the debt securities that can be purchased upon exercise, including any rights to receive payments of principal, premium or interest on the underlying debt securities or to enforce covenants in the applicable indenture. Until any rights to acquire warrants are exercised, the holder of the rights will not have any rights of holders of the warrants, including any rights to exercise the warrants and receive the underlying securities. Until any rights to purchase units are exercised, the holder of the rights will not have any rights of holders of the units, or the securities comprising such units, that can be purchased upon exercise.

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DESCRIPTION OF UNITS

We may offer and sell, from time to time, units comprised of one or more of the other securities described in this prospectus in any combination. Each unit will be issued so that the holder of the unit is also the holder of each security included in the unit. Thus, the holder of a unit will have the rights and obligations of a holder of each included security. If we issue units, they will be evidenced by unit agreements or unit certificates issued under one or more unit agreements, which will be contracts between us and the holders of the units or an agent for the holders of the units. The unit agreement under which a unit is issued may provide that the securities included in the unit may not be held or transferred separately, at any time or at any time before a specified date. The forms of unit agreements or unit certificates, as applicable, relating to the units will be filed as exhibits to the registration statement of which this prospectus is part of and/or will be incorporated by reference from reports that we file with the SEC.

The following summary of material provisions of the units and unit agreements are subject to, and qualified in their entirety by reference to, all of the provisions of the unit agreements and unit certificates applicable to a particular series of units. We urge you to read the applicable prospectus supplement, as well as the complete unit agreements and unit certificates that contain the terms of any units we may issue.

Whenever units are to be issued and sold pursuant to this prospectus, we will file a prospectus supplement relating to that offer and sale which will specify (in each case as applicable):

·	the title of the series of units;
·	identification and description of the separate securities comprising the units;
·	the price or prices at which the units will be sold;
·	the date, if any, on and after which the units, and the securities comprising such units, will be separately transferable; and
·	any other terms of such units, and the securities comprising such units, including procedures and limitations relating to distribution and exchange of such units.

25

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LEGAL MATTERS

Certain legal matters, including the validity of the issuance of the securities offered by this prospectus, will be passed upon for us by Stradling Yocca Carlson & Rauth, P.C., Newport Beach, California. If the validity of any securities is also passed upon by counsel for the underwriters of an offering of those securities, that counsel will be named in the prospectus supplement relating to that offering.

EXPERTS

The audited consolidated financial statements of Acacia Research Corporation and management’s assessment of the effectiveness of internal control over financial reporting (which is included in Management’s Report on Internal Control over Financial Reporting) incorporated by reference in this prospectus by reference toand elsewhere in the Annual Report on Form 10-K for the year ended December 31, 2008registration statement have been so incorporated by reference in reliance onupon the reports of Grant Thornton LLP, an independent registered public accounting firm, given onaccountants, upon the authority of said firm as experts in auditingaccounting and accounting.auditing.

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INCORPORATION OF CERTAIN DOCUMENTS BY REFERENCE

The financial statementsSEC allows us to “incorporate” into this prospectus information that we file with the SEC in other documents. This means that we can disclose important information to you by referring to other documents that contain that information. Any information that we incorporate by reference into this prospectus is considered part of Acacia Research Corporation incorporatedthis prospectus.

Information contained in this prospectus and information that we file with the SEC in the future and incorporate by reference in this prospectus automatically modifies and supersedes previously filed information, including information in previously filed documents or reports that have been incorporated by reference in this prospectus, to the Annual Reportextent the new information differs from or is inconsistent with the previously filed information. Any statement so modified will be deemed to constitute a part of this prospectus only as so modified, and any statement so superseded will be deemed not to constitute a part of this prospectus. For more information, see the section entitled “About this Prospectus.”

We incorporate by reference, as of their respective dates of filing, the documents listed below that we have filed with the SEC and any future documents that we file with the SEC pursuant to Sections 13(a), 13(c), 14 or 15(d) of the Exchange Act, including any documents filed after the date on Form 10-K forwhich the year ended December 31, 2008 have been so incorporated in reliance onregistration statement of which this prospectus is a part is initially filed until the report of PricewaterhouseCoopers LLP, an independent registered public accounting firm, given on the authority of said firm as experts in auditing and accounting.

LEGAL MATTERS

The validityoffering of the securities offered herebycovered by this prospectus has been completed, other than, in each case, documents or information deemed to have been “furnished” and not “filed” in accordance with SEC rules:

	·	our Annual Report on Form 10-K for the fiscal year ended December 31, 2019, or the Annual Report, filed with the SEC on March 16, 2020;
	·	our Quarterly Report on Form 10-Q for the fiscal quarter ended March 31, 2020, filed with the SEC on May 11, 2020, our Quarterly Report on Form 10-Q for the fiscal quarter ended June 30, 2020, filed with the SEC on August 10, 2020, and our Quarterly Report on Form 10-Q for the fiscal quarter ended September 30, 2020, filed with the SEC on November 9, 2020;
	·	the information specifically incorporated by reference into the Annual Report from our Definitive Proxy Statement on Schedule 14A, filed with the SEC on April 10, 2020;
	·	our Current Reports on Form 8-K as filed with the SEC on each of January 13, 2020, February 21, 2020, March 3, 2020, March 12, 2020, May 18, 2020, June 4, 2020, June 10, 2020, June 25, 2020, July 7, 2020, July 20, 2020, August 3, 2020 and October 20, 2020; and
	·	the description of our common stock contained in our registration statement on Form 8-A, filed with the SEC on December 19, 2002, as amended by Form 8-A/A, filed with the SEC on August 14, 2008, including any amendment or report filed for the purpose of updating such description.

Each of these filings is incorporated by reference into this prospectus. We will provide to each person, including any beneficial owner to whom this prospectus is delivered, a copy of any document that is incorporated by reference in this prospectus. You may obtain a copy of these documents, at no cost, from our website (www.acaciaresearch.com) or by contacting us using the following information:

Jennifer Graff

Secretary

Acacia Research Corporation

4 Park Plaza, Suite 550

Irvine, California 92614

Exhibits to the documents will not be passed uponsent, however, unless those exhibits have specifically been incorporated by reference in this prospectus.

You should rely only on the information contained in this prospectus, in any accompanying prospectus supplement, or in any document incorporated by reference herein or therein. We have not authorized anyone to provide you with any different information. We take no responsibility for, usand can provide no assurance as to the reliability of, any other information that others may provide to you. The information contained in this prospectus, in any applicable prospectus supplement, and in the documents incorporated by Stradling Yocca Carlson & Rauth, a Professional Corporation.reference herein or therein, is accurate only as of the date such information is presented. Our business, financial condition, results of operations, liquidity and future prospects may have changed since those respective dates.

27

WHERE YOU CAN FIND MORE INFORMATION

We are a reporting company and file annual, quarterly and current reports, proxy statements andas well as other information, with the SEC. We have filedOur filings with the SEC a registration statementare available on Form S-3 under the Securities Act with respect to the securities we are offering under this prospectus. This prospectus does not contain all of the information set forth in the registration statement and the exhibits to the registration statement. For further information with respect to us and the securities we are offering under this prospectus, we refer you to the registration statement and the exhibits and schedules filed as a part of the registration statement. You may read and copy the registration statement, as well as our reports, proxy statements and other information, at the SEC’s Public Reference Roomwebsite at 100 F Street, N.E., Washington, D.C. 20549. You can request copies of these documents by writing to the SEC and paying a fee for the copying cost. Please call the SEC at 1-800-SEC-0330 for more information about the operation of the Public Reference Room. The SEC maintains an internet site thatwww.sec.gov, which contains reports, proxy and information statements, and other information regarding issuers that file electronically with the SEC, where our SEC filings are also available. The address of the SEC’s web siteelectronically.

This prospectus is “http://www.sec.gov.” We maintain a website at www.acaciares.com. Information contained in or accessible through our website does not constitute a part of this prospectus.

INCORPORATION OF CERTAIN INFORMATION BY REFERENCE

The SEC allows us to “incorporate by reference” information that we file with it into this prospectus, 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 referencea registration statement that we filed with the SEC. As permitted by SEC prior to the date ofrules, this prospectus while informationand any accompanying prospectus supplement that we may file, later with the SEC will automatically update and supersede the information in this prospectus. We incorporate by reference into this registration statement and prospectus the documents listed below, and any future filings we will make with the SEC under Sections 13(a), 13(c), 14 or 15(d) of the Exchange Act after the date of the initial registration statement but prior to effectivenesswhich form a part of the registration statement, and after the date of this prospectus but prior to the termination of the offering of the securities covered by this prospectus (other than current reports or portions thereof furnished under Item 2.02 or Item 7.01 of Form 8-K):

1.	our Annual Report on Form 10-K for the fiscal year ended December 31, 2008, filed with the SEC on February 26, 2009;

2.	our Current Reports on Form 8-K filed with the SEC on January 5, 2009 and February 19, 2009; and

27

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3.	the description of our common stock contained in the Registration Statement on Form 8-A as filed with the SEC on December 19, 2002, including any amendment or reports filed for the purpose of updating such description.

We will provide each person, including any beneficial owner, to whom a prospectus is delivered, a copy of any ordo not contain all of the information that has been incorporated by reference in this prospectus but not delivered with the prospectus, including exhibits that are specifically incorporated by reference into such documents. We will provide this information upon written or oral request at no charge to the requester. The request for this information must be made to the following:

Acacia Research Corporation

Attention:  Investor Relations

500 Newport Center Drive, 7th Floor

Newport Beach, California 92660

Telephone:  (949) 480-8300

DISCLOSURE OF COMMISSION POSITION ON INDEMNIFICATION FOR

SECURITIES ACT LIABILITY

Our officers and directors are required to exercise good faith and high integrityis included in the management of our affairs. Our charter documents provide, however, that our officersregistration statement. The registration statement contains more information regarding us, the selling stockholders, and directors shall have no liability for losses or liabilities incurred, except as such losses or liabilities relate tothe securities offered by us and the selling stockholders, including certain exhibits. You can obtain a violationcopy of the duty of loyalty, a breach of good faith, intentional misconduct or knowing violation of law, approval of an improper dividend or stock repurchase or receipt of an improper benefit, in accordance with Delaware law, and they may be indemnified by us toregistration statement from the maximum extent permitted bySEC at the Delaware General Corporation law.

Insofar as indemnification for liabilities arising under the Securities Act may be permitted to directors, officers and controlling persons of the registrant pursuant to the foregoing provisions, or otherwise, the registrant has been advised that in the opinion of the Securities and Exchange Commission such indemnification is against public policy as expressed in the Securities Act and is, therefore, unenforceable.

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website referenced above.

YOU SHOULD RELY ONLY ON THE INFORMATION CONTAINED IN THIS PROSPECTUS. WE HAVE NOT AUTHORIZED ANYONE TO PROVIDE YOU WITH INFORMATION DIFFERENT FROM THAT CONTAINED IN THIS PROSPECTUS. WE ARE OFFERING TO SELL, AND SEEKING OFFERS TO BUY, SHARES OF OUR COMMON STOCK ONLY IN JURISDICTIONS WHERE OFFERS AND SALES ARE PERMITTED. THE INFORMATION CONTAINED IN THIS PROSPECTUS IS ACCURATE ONLY AS OF THE DATE OF THIS PROSPECTUS, REGARDLESS OF THE TIME OF DELIVERY OF THIS PROSPECTUS OR OF ANY SALE OF OUR COMMON STOCK.

$55,786,321 ACACIA RESEARCH CORPORATION Common Stock Warrants

TABLE OF CONTENTS
	Page
About this Prospectus	6
Prospectus Summary	7
Risk Factors	12
Cautionary Statement Concerning Forward-Looking Information	23			____________
Use of Proceeds	23
Plan of Distribution	23			PROSPECTUS
Description of Warrants	25
Experts	27			____________
Legal Matters	27
Where You Can Find More Information	27			Acacia Research Corporation
Incorporation of Certain Information by Reference	27
Disclosure of Commission Position on Indemnification for Securities Act Liability	28
____________				____________

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PART II

INFORMATION NOT REQUIRED IN PROSPECTUS

Item 14. Other Expenses Ofof Issuance And Distribution

and Distribution.

The following table sets forth an itemization of the various costs and expenses, other than underwriting discounts and commissions, payable by the registrantus in connection with the offeringissuance and distribution of ourthe securities being registered. Exceptregistered hereunder. All of the amounts shown are estimated except for the SEC registration fee, all the amounts shown are estimates.

		Amount to be paid
SEC registration fee		$	2,192
Printing expenses		$	10,000
Legal fees and expenses		$	17,500
Miscellaneous		$	5,000
Total		$	34,692

fee.

SEC registration fee	$	63,079.45
FINRA filing fees	$	*
Legal fees and expenses	$	*
Accounting fees and expenses	$	*
Miscellaneous	$	*
Total expenses	$	*

*

These fees and expenses depend on the securities offered and the number of issuances, and accordingly cannot be estimated at this time

Item 15. Indemnification Ofof Directors And Officers

and Officers.

We are incorporated under the laws of the State of Delaware. Section 145 of the Delaware General Corporation Law, or DGCL provides that a Delaware corporation may indemnify directors and officers as well as other employees and individuals against expenses (including attorneys' fees), judgments, fines and amounts paid in settlement in connection with specified actions, suitsany persons who are, or proceedings,are threatened to be made, parties to any threatened, pending or completed action, suit or proceeding, whether civil, criminal, administrative or investigative (other than an action by or in the right of such corporation), by reason of the fact that such person was an officer, director, employee or agent of such corporation, - a derivative action)or is or was serving at the request of such corporation as an officer, director, employee or agent of another corporation or enterprise. The indemnity may include expenses (including attorneys’ fees), if theyjudgments, fines and amounts paid in settlement actually and reasonably incurred by such person in connection with such action, suit or proceeding, provided that such person acted in good faith and in a manner theyhe or she reasonably believed to be in or not opposed to the corporation’s best interests of the corporation and, with respect to any criminal action or proceedings,proceeding, had no reasonable cause to believe theirthat his or her conduct was unlawful.

A similar standard is applicable in the case of derivative actions, except that indemnification only extends to expenses (including attorneys' fees) actually and reasonably incurred in connection with the defense or settlement of such action, and the statute requires court approval before there can be any indemnification where the person seeking indemnification has been found liable to the corporation. The statute provides that it is not exclusive of other indemnification that may be granted by a corporation's certificate of incorporation, bylaws, disinterested director vote, stockholder vote, agreement or otherwise.

As permitted byillegal. Section 145 of the Delaware General Corporation Law, Article VIIDGCL further authorizes a corporation to purchase and maintain insurance on behalf of our restatedany indemnified person against any liability asserted against and incurred by such person in any indemnified capacity, or arising out of such person’s status as such, regardless of whether the corporation would otherwise have the power to indemnify such person under the DGCL.

Section 102(b)(7) of the DGCL permits a corporation to provide in its certificate of incorporation as amended, provides:

“No personthat a director of the corporation shall not be personally liable to the Corporationcorporation or its stockholders for monetary damages for breach of fiduciary dutyduties as a director, including without limitationexcept for serving on a committee of the Board of Directors, exceptliability for any:

	·	breach of a director’s duty of loyalty to the corporation or its stockholders;
	·	act or omission not in good faith or that involves intentional misconduct or a knowing violation of law;
	·	unlawful payment of dividends or redemption of shares; or
	·	transaction from which the director derives an improper personal benefit.

Our Charter authorizes us to, the extent such exemption from liability or limitation thereof is not permitted under the DGCL as the same exists or hereafter may be amended. If the DGCL is amended after the date of the filing of this Certificate of Incorporation to authorize corporate action further eliminating or limiting the personal liability ofand our Bylaws provide that we must, indemnify our directors then the liability of a director of the Corporation shall be eliminated or limitedand officers to the fullest extent authorized by the DGCL and also pay expenses incurred in defending any such proceeding in advance of its final disposition upon delivery of an undertaking, by or on behalf of an indemnified person, to repay all amounts so advanced if it should be determined ultimately that such person is not entitled to be indemnified under this section or otherwise.

II-1

As permitted by the DGCL, as so amended. Any amendment, repeal or modificationwe have entered into indemnification agreements with each of this Article VII shall not adversely affect any right or protection of a director of the Corporation existing hereunder with respect to any act or omission occurring prior to such amendment, repeal or modification.”

We have purchased insurance on behalf of any person who is or was a director, officer, employee or agent of our company, or is or was serving at the request of our company as a director, officer, employee or agent of another corporation, partnership, joint venture, trust or other enterprise against any liability asserted against him and incurred by him in any such capacity, or arising out of his status as such, whether or not our company would have the power to indemnify him against such liability under the provisions of our restated certificate of incorporation, as amended.

Any underwriting agreements that we may enter into will likely provide for the indemnification of us, our controlling persons, our directors and certain of our officers. These agreements require us to indemnify these individuals to the fullest extent permitted under Delaware law against liabilities that may arise by reason of their service to us, and to advance expenses incurred as a result of any proceeding against them as to which they could be indemnified.

We have an insurance policy covering our officers by the underwriters againstand directors with respect to certain liabilities, including liabilities arising under the Securities Act or otherwise.

Any underwriting agreement or similar agreement that we enter into in connection with an offer of securities pursuant to this registration statement may provide for indemnification by any underwriters of us, our directors, our officers who sign the registration statement and our controlling persons for some liabilities, including liabilities arising under the Securities Act.

II-1

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Item 16.  Exhibits

Exhibit Number	Description
1.1	Form of Underwriting Agreement, if any (1)
4.1	Form of Warrant Agreement (1)
5.1	Opinion of Stradling Yocca Carlson & Rauth, a Professional Corporation
23.1	Consent of Grant Thornton LLP
23.2	Consent of PricewaterhouseCoopers LLP
23.3	Consent of Stradling Yocca Carlson & Rauth, a Professional Corporation (included in Exhibit 5.1 hereto)
24.1	Power of Attorney (included on signature page hereto)

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(1)	To be filed as an exhibit to a Current Report on Form 8-K and incorporated herein by reference.

Exhibits.

See the section entitled “Exhibit Index” that appears immediately preceding the signature page to this registration statement.

Item 17.  Undertakings.

a.

(a) The undersigned registrant hereby undertakes:

   1.

(1) To file, during any period in which offers or sales are being made, a post-effective amendment to this registration statement:

(i)

to include any prospectus required by Section 10(a)(3) of the Securities Act;

(ii)

to reflect in the prospectus any facts or events arising after the effective date of the registration statement (or the most recent post-effective amendment thereof) which, individually or in the aggregate, represent a fundamental change in the information set forth in the registration statement. Notwithstanding the foregoing, any increase or decrease in volume of securities offered (if the total dollar value of securities offered would not exceed that which was registered) and any deviation from the low or high end of the estimated maximum offering range may be reflected in the form of prospectus filed with the SEC pursuant to Rule 424(b) if, in the aggregate, the changes in volume and price represent no more than a 20 percent change in the maximum aggregate offering price set forth in the “Calculation of Registration Fee” table in the effective registration statement;

(iii)

to include any material information with respect to the plan of distribution not previously disclosed in this registration statement or any material change to such information in this registration statement;

(i) To include any prospectus required by Section 10(a)(3) of the Securities Act of 1933, as amended (the "Securities Act");

(ii) To reflect in the prospectus any facts or events arising after the effective date of this registration statement (or the most recent post-effective amendment thereof) which, individually or in the aggregate, represent a fundamental change in the information set forth in this registration statement. Notwithstanding the foregoing, any increase or decrease in volume of securities offered (if the total dollar value of securities offered would not exceed that which was registered) and any deviation from the low or high end of the estimated maximum offering range may be reflected in the form of prospectus filed with the SEC pursuant to Rule 424(b) if, in the aggregate, the changes in volume and price represent no more than a 20% change in the maximum aggregate offering price set forth in the "Calculation of Registration Fee" table in the effective registration statement;

(iii) To include any material information with respect to the plan of distribution not previously disclosed in this registration statement or any material change to such information in this registration statement; provided, however,, that paragraphs (a)(1)(i), (a)(1)(ii) and (a)(1)(iii) of this section do not apply if the information required to be included in a post-effective amendment by those paragraphs is contained in reports filed with or furnished to the SEC by the registrant pursuant to Section 13 or Section 15(d) of the Securities Exchange Act of 1934, as amended (the "Exchange Act") that are incorporated by reference in this registration statement, or is contained in a form of prospectus filed pursuant to Rule 424(b) that is part of thethis registration statement;

2.statement.

(2) That, for the purpose of determining any liability under the Securities Act, each such post-effective amendment shall be deemed to be a new registration statement relating to the securities offered therein, and the offering of such securities at that time shall be deemed to be the initial bona fide offering thereof; and

3.thereof.

(3) To remove from registration by means of a post-effective amendment any of the securities being registered which remain unsold at the termination of the offering.

II-2

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4.

(4) That, for the purpose of determining liability under the Securities Act to any purchaser:

(i)

each (A) Each prospectus filed by the registrant pursuant to Rule 424(b)(3) shall be deemed to be part of the registration statement as of the date the filed prospectus was deemed part of and included in the registrant pursuant to Rule 424(b)(3) shall be deemed to be part of this registration statement as of the date the filed prospectus was deemed part of and included in this registration statement; and II-2 (ii) each (B) Each prospectus required to be filed pursuant to Rule 424(b)(2), (b)(5), or (b)(7) as part of a registration statement in reliance on Rule 430B relating to an offering made pursuant to Rule 415(a)(1)(i), (vii), or (x) for the purpose of providing the information required by Section 10(a) of the Securities Act shall be deemed to be part of and included in this registration statement as of the earlier of the date such form of prospectus is first used after effectiveness or the date of the first contract of sale of securities in the offering described in the prospectus. As provided in Rule 430B, for liability purposes of the issuer and any person that is at that date an underwriter, such date shall be deemed to be a new effective date of the registration statement relating to the securities in the registration statement to which that prospectus relates, and the offering of such securities at that time shall be deemed to be the initial bona fide offering thereof; provided, however, that no statement made in a registration statement or prospectus that is part of this registration statement or made in a document incorporated or deemed incorporated by reference into this registration statement or prospectus that is part of this registration statement will, as to a purchaser with a time of contract of sale prior to such effective date, supersede or modify any statement that was made in this registration statement or prospectus that was part of this registration statement or made in any such document immediately prior to such effective date. (5), or (b)(7) as part of a registration statement in reliance on Rule 430B relating to an offering made pursuant to Rule 415(a)(1)(i), (vii), or (x) for the purpose of providing the information required by Section 10(a) of the Securities Act shall be deemed to be part of and included in the registration statement as of the earlier of the date such form of prospectus is first used after effectiveness or the date of the first contract of sale of securities in the offering described in the prospectus. As provided in Rule 430B, for liability purposes of the issuer and any person that is at that date an underwriter, such date shall be deemed to be a new effective date of the registration statement relating to the securities in the registration statement to which that prospectus relates, and the offering of such securities at that time shall be deemed to be the initial bona fide offering thereof. Provided, however, that no statement made in a registration statement or prospectus that is part of the registration statement or made in a document incorporated or deemed incorporated by reference into the registration statement or prospectus that is part of the registration statement will, as to a purchaser with a time of contract of sale prior to such effective date, supersede or modify any statement that was made in the registration statement or prospectus that was part of the registration statement or made in any such document immediately prior to such effective date. 5. That, for the purpose of determining liability of the registrant under the Securities Act to any purchaser in the initial distribution of the securities,securities: the undersigned registrant undertakes that in a primary offering of securities of the undersigned registrant pursuant to this registration statement, regardless of the underwriting method used to sell the securities to the purchaser, if the securities are offered or sold to such purchaser by means of any of the following communications, the undersigned registrant will be a seller to the purchaser and will be considered to offer or sell such securities to such purchaser: (i) any preliminary prospectus or prospectus of the undersigned registrant relating to the offering required to be filed pursuant to Rule 424; (ii) any free writing prospectus relating to the offering prepared by or on behalf of the undersigned registrant or used or referred to by the undersigned registrant; (iii) the portion of any other free writing prospectus relating to the offering containing material information about the undersigned registrant or its securities provided by or on behalf of the undersigned registrant; and (iv) any other communication that is an offer in the offering made by the undersigned registrant to the purchaser. (i) any preliminary prospectus or prospectus of the undersigned registrant relating to the offering required to be filed pursuant to Rule 424; (ii) any free writing prospectus relating to the offering prepared by or on behalf of the undersigned registrant or used or referred to by the undersigned registrant; (iii) the portion of any other free writing prospectus relating to the offering containing material information about the undersigned registrant or its securities provided by or on behalf of the undersigned registrant; and (iv) any other communication that is an offer in the offering made by the undersigned registrant to the purchaser. (b) The undersigned registrant hereby undertakes that, for purposes of determining any liability under the Securities Act, each filing of the registrant's annual report pursuant to sectionSection 13(a) or Section 15(d) of the Exchange Act (and, where applicable, each filing of an employee benefit plan’splan's annual report pursuant to Section 15(d) of the Exchange Act) that is incorporated by reference in thethis registration statement shall be deemed to be a new registration statement relating to the securities offered therein,herein, and the offering of such securities at that time shall be deemed to be the initial bona fide offering thereof. (c)    The undersigned registrant hereby undertakes to deliver or cause to be delivered with the prospectus, to each person to whom the prospectus is sent or given, the latest annual report, to security holders that is incorporated by reference in the prospectus and furnished pursuant to and meeting the requirements of Rule 14a-3 or Rule 14c-3 under the Exchange Act; and, where interim financial information required to be presented by Article 3 of Regulation S-X are not set forth in the prospectus, to deliver, or cause to be delivered to each person to whom the prospectus is sent or given, the latest quarterly report that is specifically incorporated by reference in the prospectus to provide such interim financial information. II-3 (d) Insofar as indemnification for liabilities arising under the Securities Act may be permitted to directors, officers and controlling persons of the registrant pursuant to the foregoing provisions, or otherwise, the registrant has been advised that in the opinion of the SEC such indemnification is against public policy as expressed in the Act and is, therefore, unenforceable. In the event that a claim for indemnification against such liabilities (other than the payment by the registrant of expenses incurred or paid by a director, officer or controlling person of the registrant in the successful defense of any action, suit or proceeding) is asserted by such director, officer or controlling person in connection with the securities being registered, the registrant will, unless in the opinion of its counsel the matter has been settled by controlling precedent, submit to a court of appropriate jurisdiction the question whether such indemnification by it is against public policy as expressed in the Act and will be governed by the final adjudication of such issue. (e) (d) The undersigned registrant hereby undertakes that: (1)    For purposes of determining any liability under the Securities Act, the information omitted from the form of prospectus filed as part of this registration statement in reliance upon Rule 430A and contained in a form of prospectus filed by the registrant pursuant to Rule 424(b)(1) or (4) or 497(h) under the Securities Act shall be deemed to be part of this registration statement as of the time it was declared effective. (2)    Forfile an application for the purpose of determining any liabilitythe eligibility of the trustee to act under subsection (a) of section 310 of the SecuritiesTrust Indenture Act each post-effective amendment that contains a form(“Act”) in accordance with the rules and regulations prescribed by the SEC under section 305(b)(2) of prospectus shall be deemed to be a new registration statement relating to the securities offered therein, and the offering of such securities at that time shall be deemed to be the initial bona fide offering thereof.Act. II-3 EXHIBIT INDEX Exhibit No. Description 1.1 Form of Underwriting Agreement* 4.1 Amended and Restated Certificate of Incorporation of Acacia Research Corporation (as currently in effect) (incorporated herein by reference to Exhibit 3.1 of the registrant’s Form 10-K for the fiscal year ended December 31, 2019, filed with the SEC on March 16, 2020  (File No. 001-37721)) 4.2 Amended and Restated Certificate of Designations, Preferences and Rights of Series A Convertible Preferred Stock, as filed with the Delaware Secretary of State on January 7, 2020 (incorporated by reference to Appendix B to the registrant’s Definitive Proxy Statement on Schedule 14A, filed with the SEC on January 17, 2020 (File No. 001-37721) 4.3 Second Amended and Restated Bylaws of Acacia Research Corporation (as currently in effect) (incorporated herein by reference to Exhibit 3.1 of the registrant’s Quarterly Report on Form 10-Q for the fiscal quarter ended June 30, 2020, filed with the SEC on August 10, 2020 (File No. 001-37721)) 4.4 Form of Certificate of Designation of Preferred Stock* 4.5 Form of Indenture± 4.6 Form of Warrant Agreement (including form of warrant)* 4.7 Form of Rights Agreement (including form of rights certificate)* 4.8 Form of Unit Agreement (including form of unit certificate)* 5.1 Opinion of Stradling Yocca Carlson & Rauth, P.C.± 23.1 Consent of Independent Registered Public Accounting Firm± 23.2 Consent of Stradling Yocca Carlson & Rauth, P.C. (included in Exhibit 5.1)± 24.1 Power of Attorney (included on the signature page of this registration statement)± 25.1 Statement of Eligibility of Trustee** ± Filed herewith. * To be filed by amendment to this registration statement, or as an exhibit to a document to be incorporated by reference into this registration statement, in each case in connection with a particular offering of the securities. ** To be filed separately under electronic form type 305B2 under Rule 305(b)(2) of the Trust Indenture Act, if applicable. II-4 II-4 SIGNATURES Pursuant to the requirements of the Securities Act, of 1933, as amended, the registrant certifies that it has reasonable grounds to believe that itthe registrant meets all of the requirements for filing on Form S-3 and has duly caused this amended registration statement to be signed on its behalf by the undersigned, thereunto duly authorized, in the City of Newport Beach,Irvine, in the State of California, on the 27th day of February, 2009. November 9, 2020.   ACACIA RESEARCH CORPORATION By:   /s/ Paul R. Ryan Paul R. Ryan,Clifford Press         Clifford Press         Chief Executive Officer & Chairman and Director  POWER OF ATTORNEY KNOW ALL PERSONS BY THESE PRESENTS that each personindividual whose signature appears below hereby constitutes and appoints Paul R. RyanClifford Press and Clayton J. Haynes,Richard Rosenstein, and each of them, as his or her true and lawful attorneys-in-fact and agents with full power of substitution, and resubstitution, for him or her and in his or her name, place and stead, in any and all capacities, to sign any and all amendments, (includingincluding post-effective amendments)amendments, to this registration statement, and to sign any registration statement for the same offering covered by this registration statement that is to be effective upon filing pursuant to Rule 462(b) promulgated under the Securities Act, and all post-effective amendments thereto, and to file the same, with all exhibits thereto and otherall documents in connection therewith, making such changes in this registration statement as such attorneys-in-fact and agents so acting deem appropriate, with the Securities and Exchange Commission,SEC, granting unto said attorneys-in-fact and agents, and each of them, full power and authority to do and perform each and every act and thing requisite and necessary to be done in connection therewith,with respect to the offering of securities contemplated by this registration statement, as fully to all intents and purposes as he or she might or could do in person, hereby ratifying and confirming all that said attorneys-in-fact and agents or any of them, or his, her or their substitute or his substitutes, or substitute, may lawfully do or cause to be done by virtue hereof. Pursuant to the requirements of the Securities Act of 1933, as amended, this registration statement has been signed by the following persons in the capacities and on the dates indicated. DateName   SignatureTitle   TitleDate           February 27, 2009 /s/ Paul R. RyanClifford Press   Chief Executive Officer (Principal Executive Officer) and Director   Paul R. RyanNovember 9, 2020 Clifford Press   and Chairman of the Board of Directors February 27, 2009 /s/ Clayton J. Haynes Chief Financial Officer (Principal Financial Officer Clayton J. Haynes and (Principal AccountingExecutive Officer) February 27, 2009 /s/ Robert L. Harris President and Director Robert L. Harris               February 27, 2009 /s/ Richard Rosenstein   /s/ William S. AndersonChief Financial Officer   DirectorNovember 9, 2020 Richard Rosenstein   William S. Anderson(Principal Financial Officer)               February 27, 2009 /s/ Li Yu   /s/ Fred A. deBoomCorporate Controller   DirectorNovember 9, 2020 Li Yu   Fred A. deBoom(Principal Accounting Officer)               February 27, 2009 /s/ Alfred V. Tobia, Jr.   /s/ Edward W. FrykmanPresident, Chief Investment Officer and Director   DirectorNovember 9, 2020 Alfred V. Tobia, Jr.     Edward W. Frykman               February 27, 2009 /s/ G. Louis Graziadio, IIIMaureen O’Connell   Director and Chairman November 9, 2020 Maureen O’Connell     G. Louis Graziadio, III /s/ Katharine Wolanyk Director November 9, 2020 Katharine Wolanyk /s/ Isaac T. Kohberg Director November 9, 2020 Isaac T. Kohberg /s/ Jonathan Sagal Director November 9, 2020 Jonathan Sagal     II-5 EXHIBIT INDEX Exhibit Number Description   1.1II-5 Form of Underwriting Agreement, if any (1) 4.1 Form of Warrant Agreement (1) 5.1 Opinion of Stradling Yocca Carlson & Rauth, a Professional Corporation 23.1 Consent of Grant Thornton LLP 23.2 Consent of PricewaterhouseCoopers LLP 23.3 Consent of Stradling Yocca Carlson & Rauth, a Professional Corporation (included in Exhibit 5.1 hereto) 24.1 Power of Attorney (included on signature page hereto) (1) To be filed as an exhibit to a Current Report on Form 8-K and incorporated herein by reference. II-6