As filed with the Securities and Exchange Commission on August 22, 20179, 2019

Registration No. 333-219406333-                

UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

WASHINGTON, DC 20549

FORMS-3

REGISTRATION STATEMENT

UNDER

THE SECURITIES ACT OF 1933

BIOLASE, INC.

(Exact name of registrant as specified in its charter)

4 Cromwell, Irvine, California 92618

(949)361-1200

(Address, including zip code, and telephone number, including area code, of registrant’s principal executive offices)

Todd A. Norbe

President and Chief Executive Officer
Biolase,

BIOLASE, Inc.

4 Cromwell

Irvine, California 92618

(949)361-1200

(Name, address, including zip code, and telephone number, including area code, of agent for service)

Copy to:

Michael A. Gordon

Beth E. Peev
Berg

Sidley Austin LLP

One South Dearborn

Chicago, Illinois 60603

(312)853-7000

Approximate date of commencement of proposed sale to the public: From time to time on or after the effective date of the registration statement.

If the only securities being registered on this Formform are being offered pursuant to dividend or interest reinvestment plans, please check the following box.  ☐

If any of the securities being registered on this Form are to be offered on a delayed or continuous basis pursuant to Rule 415 under the Securities Act of 1933, other than securities offered only in connection with dividend or interest reinvestment plans, check the following box.  ☒

If this Formform is filed to register additional securities for an offering pursuant to Rule 462(b) under the Securities Act, please check the following box and list the Securities Act registration statement number of the earlier effective registration statement for the same offering.  ☐

If this Formform is a post-effective amendment filed pursuant to Rule 462(c) under the Securities Act, check the following box and list the Securities Act registration statement number of the earlier effective registration statement for the same offering.  ☐

If this Form is a registration statement pursuant to General Instruction I.D. or a post-effective amendment thereto that shall become effective upon filing with the Commission pursuant to Rule 462(e) under the Securities Act, check the following box.  ☐

If this Form is a post-effective amendment to a registration statement filed pursuant to General Instruction I.D. filed to register additional securities or additional classes of securities pursuant to Rule 413(b) under the Securities Act, check the following box.  ☐

Indicate by check mark whether the registrant is a large accelerated filer, an accelerated filer, anon-accelerated filer, smaller reporting company, or an emerging growth company. See the definitions of “large accelerated filer,” “accelerated filer,” “smaller reporting company,” and “emerging growth company” inRule 12b-2 of the Exchange Act.

If an emerging growth company, indicate by check mark if the registrant has elected not to use the extended transition period for complying with any new or revised financial accounting standards provided pursuant to Section 7(a)(2)(B) of the Securities Act.  ☐

CALCULATION OF REGISTRATION FEE

The information in this preliminary prospectus is not complete and may be changed. The selling stockholdersWe may not resellsell these securities until the registration statementRegistration Statement filed with the Securities and Exchange Commission is declared effective. This preliminary prospectus is not an offer to sell these securities, nor is it a solicitation of offers to buy these securities, in any statejurisdiction where the offer or sale is not permitted.

SUBJECT TO COMPLETION, DATED AUGUST 22, 20179, 2019

PROSPECTUS

11,990,271 Shares

BIOLASE, INC.

Common Stock$50,000,000 Aggregate Offering Price of

COMMON STOCK, PREFERRED STOCK, DEBT SECURITIES, WARRANTS, RIGHTS AND UNITS

BIOLASE, Inc., a Delaware corporation, may offer and sell from time to time, in one or more offerings, common stock, preferred stock, debt securities, warrants, rights and units for an aggregate initial offering price up to $50,000,000 in amounts, at prices and on terms that BIOLASE, Inc. will determine at the time of the offering.

This prospectus relatesdescribes general terms that apply to these securities. When we decide to sell a particular class or series of these securities, we will provide specific terms of the possible resalesecurities, including the initial offering price and the aggregate amount of up to 11,990,271 shares of our common stock, $0.001 par value per share, which includes 3,925,871 shares of our common stock that may be issued upon the exercise of warrants, by the selling stockholders identifiedoffering, in this prospectusone or inmore supplements to this prospectus. The sharesAny prospectus supplement may also add, update or change information contained in this prospectus. You should carefully read this prospectus and the warrants were issuedapplicable prospectus supplement, as well as the documents incorporated or deemed to be incorporated by reference in this prospectus, before you invest in our securities.

We may offer and sell these securities in the same offering or in separate offerings; to or through underwriters, dealers or agents; or directly to purchasers. The names of any underwriters, dealers or agents involved in the sale of our securities, their compensation and any over-allotment options held by them will be described in the applicable prospectus supplement. For a more complete description of the plan of distribution with respect to the selling stockholders in connection with a previously disclosed April 18, 2017 private placement.  We are registering the shares to provide the selling stockholders with freely tradable securities.  This prospectus does not necessarily mean that the selling stockholders will offer or sell those shares.  Up to 8,064,400 shares may be sold from time to time after the effectiveness of the registration statement, of which this prospectus forms a part, and up to 3,925,871 shares may be sold from time to time after October 18, 2017, which is the date the warrants pursuant to which such shares may be issued become exercisable.

We will receive no proceeds from any sale by the selling stockholders of the shares of our common stocksecurities covered by this prospectus, but we have agreed to pay certain expenses relating tosee the registration of such shares.  The selling stockholders may from time to time offer and resell, transfer or otherwise dispose of any or all of the shares of our common stock covered by this prospectus through underwriters or dealers, directly to purchasers or through broker-dealers or agents.  Seesection entitled “Plan of Distribution.”Distribution” beginning on page 12 of this prospectus.

Our common stock trades on the NASDAQThe Nasdaq Capital Market under the symbol “BIOL.” On August 18, 2017,8, 2019, the closinglast reported sale price for our common stock as reported on the NASDAQThe Nasdaq Capital Market was $0.60$1.55 per share. As of August 8, 2019, the aggregate market value of our common stock held by ournon-affiliates, as calculated pursuant to the rules of the Securities and Exchange Commission, was $12,305,369. Pursuant to General Instruction I.B.6 of FormS-3, in no event will we sell securities in a public offering with a value exceeding more thanone-third of our “public float” (the market value of our common stock held by ournon-affiliates) in any12-month period so long as our public float remains below $75,000,000. We have not sold any securities in reliance on General Instruction I.B.6 of FormS-3 during the 12 calendar months prior to and including the date of this prospectus.

Investing in our securities involves certainsubstantial risks. See “Risk Factors”You should consider the “Risk Factors” on page 32 of this prospectus, in the documents that are incorporated by reference into this prospectus and, if applicable, in risk factors described in any applicableaccompanying prospectus supplement for certain risks you should consider.  You should read the entire prospectus carefully before you make your investment decision.buying any of our securities.

Neither the Securities and Exchange Commission nor any state securities commission has approved or disapproved of these securities or determined ifpassed upon the adequacy or accuracy of this prospectus is truthful or complete.prospectus. Any representation to the contrary is a criminal offense.

The date of this prospectus is, 2017 2019

TABLE OF CONTENTS

This prospectus is part of a “shelf” registration statement on FormS-3that we have filed with the Securities and Exchange Commission (the “SEC”). using a “shelf” registration process. Under thethis shelf registration statement,process, we may, from time to time, sell any combination of the selling stockholders may offer and resell up to 11,990,271 shares of our common stock, which includes 3,925,971 shares of our common stock that may be issued upon the exercise of warrants,securities described in this prospectus in one or more offerings.  The exhibitsofferings up to the registration statement containaggregate amount of $50,000,000.

This prospectus provides you with a general description of the full text of certain contracts and other important documentssecurities we have summarizedmay offer. A prospectus supplement may add to, update or change information contained in this prospectus.  Since these summaries may not contain allprospectus, and, accordingly, to the extent inconsistent, information in this prospectus is superseded by the information that youin any prospectus supplement.

A prospectus supplement may find important in deciding whether to purchase our common stock, you should reviewdescribe, as applicable: the full textterms of these documents.  The registration statementthe securities; the initial public offering price; the price paid for the securities; net proceeds; and the exhibits can be obtained fromother specific terms related to the SEC as indicated underoffering of the sections entitled “Incorporation of Certain Information by Reference” and “Where You Can Find More Information.”securities.

You should rely only on the information that we have provided or incorporated by reference in this prospectus, or any applicable prospectus supplement.  Neithersupplement, any related free writing prospectus that we normay authorize to be provided to you and the selling stockholdersother information to which we refer you. We have not authorized anyone to provide you with different or additional information. Neither we nor the selling stockholders are making an offerNo dealer, salesperson or other person is authorized to sell our common stock ingive any jurisdiction where the offerinformation or sale thereof isto represent anything not permitted.  You should not assume that the information appearingcontained in this prospectus or any applicable prospectus supplement or any related free writing prospectus that we may authorize to be provided to you. If anyone provides you with different or additional information, you should not rely on it. You should assume that the documentsinformation in this prospectus, any applicable prospectus supplement or any related free writing prospectus is accurate only as of the date on the cover of the document and that any information we have incorporated by reference herein or therein is accurate only as of the date of the document incorporated by reference, regardless of the time of delivery of this prospectus, any date other than their respective dates.applicable prospectus supplement or any related free writing prospectus, or any sale of a security. Our business, financial condition, results of operations and prospects may have changed since those dates.  You should

We urge you to carefully read carefully the entirety of this prospectus and any applicable prospectus supplement, as well astogether with the documentsinformation incorporated herein by reference in this prospectus and any applicable prospectus supplement, before making an investment decision.as described under the heading “Where You Can Find Additional Information.”

In this prospectus, unless otherwise specified or the context requires otherwise, we use the terms “company,“Company,” “we,” “us” and “our” or similar references to refer to Biolase,BIOLASE, Inc., a Delaware corporation, together with its consolidated subsidiaries.

i

CAUTIONARY STATEMENTS REGARDING FORWARD-LOOKING STATEMENTS

This prospectus, any prospectus supplement and the documents that we incorporate herein or therein by reference contain “forward-looking statements”, as defined in Section 27A of the Securities Act of 1933, as amended (the “Securities Act”), and Section 21E of the Exchange Act. Such forward-looking statements include statements, predictions, or expectations regarding market opportunities, our plans to expand our product line and clinical applications, plans to explore potential collaborations, statements regarding the effects of seasonality on revenue, operating expenses, anticipated use of proceeds from debt financing, anticipated cash needs, needs for additional financing, and any other statement that is not historical fact. Forward-looking statements are identified by the use of words such as “may,” “might,” “will,” “intend,” “should,” “could,” “can,” “would,” “continue,” “expect,” “believe,” “anticipate,” “estimate,” “predict,” “outlook,” “potential,” “plan,” “seek,” and similar expressions and variations or the negatives of these terms or other comparable terminology.

Forward-looking statements are based on the expectations, estimates, projections, beliefs, and assumptions of our management based on information available to management as of the date on which such forward-looking statement was made, all of which are subject to change. Forward-looking statements are subject to risks, uncertainties, and other factors that are difficult to predict and could cause actual results to differ materially from those stated or implied by our forward-looking statements. Factors that could cause or contribute to such differences include, but are not limited to:

Further information about factors that could materially affect the Company, including our results of operations and financial condition, is contained under the heading “Risk Factors” in this prospectus, under the heading “Risk Factors” contained in the applicable prospectus supplement and in the documents incorporated by reference herein before decidinginto this prospectus and any prospectus supplement. Except as required by law, we undertake no obligation to revise or update any forward-looking statements to reflect changed assumptions, the occurrence of anticipated or unanticipated events, new information or changes to future results over time or otherwise.

USE OF PROCEEDS

Unless otherwise indicated in the applicable prospectus supplement, we will use the net proceeds from the sale of securities offered by this prospectus for working capital, including new product development, launch and subsequentscale-ups, as well as other general corporate purposes. The timing and amount of our actual expenditures will be based on many factors, including cash flows from operations and the anticipated growth of our business. As a result, unless otherwise indicated in the applicable prospectus supplement, our management will have broad discretion to allocate the net proceeds of the offerings. Pending their ultimate use, we intend to invest the net proceeds in our common stock.short-term, investment-grade, interest-bearing instruments.

DESCRIPTION OF COMMONCAPITAL STOCK

The following summary description sets forth some of the general terms and provisions of our commoncapital stock. Because this is a summary description, it does not contain all of the information that may be important to you. For a more detailed description of our commoncapital stock, you should refer to the applicable provisions of the General Corporation Law of the State of Delaware (the “DGCL”) and our charter and bylaws as in effect at the time of any offering. Copies of our Restated Certificate of Incorporation, as amended, and our SixthSeventh Amended and Restated Bylaws are included as exhibits to the registration statement of which this prospectus forms a part.

GeneralOur Authorized Capital Stock

Under our charter, we are authorized to issue 200,000,00040,000,000 shares of our common stock, par value $0.001 per share, and 1,000,000 shares of preferred stock, par value $0.001 par value per share. As of July 21, 2017,31, 2019, there were 75,976,77921,879,632 shares of our common stock issued and outstanding and no shares of our preferred stock issued and outstanding.

Common Stock

Holders of our common stock are entitled to one vote per share. Each of our directors is elected by the affirmative vote of a majority of the votes cast with respect to such director in uncontested elections. In a contested election, each of our directors is elected by an affirmative vote of a plurality of the votes cast by the shares represented and entitled to vote with respect to the election of such director. A “contested election” is defined in our bylaws as an election with respect to which, as of the record date for the meeting at which directors are to be elected, the number of nominees exceeds the number of directors to be elected at such meeting. Vacancies on the Board of Directors may be filled by an affirmative vote oftwo-thirds of the remaining members of the Board of Directors or at a meeting of the stockholders in the manner set forth in the second preceding sentence.

Subject to any preferential rights of any outstanding shares of our preferred stock to receive dividends before any dividends may be paid on our common stock, the holders of our common stock will be entitled to share ratably in any dividends that may be declared by our Board of Directors out of funds legally available for the payment of dividends. Subject to any preferential rights of any outstanding shares of our preferred stock, in the event of our liquidation, dissolution or winding up, holders of our common stock are entitled to share ratably in the assets remaining after payment of liabilities and the liquidation preferences of any outstanding preferred stock. Our common stock does not carry any redemption rights or any preemptive rights enabling a holder to subscribe for, or receive shares of, any class of our common stock or any other securities convertible into shares of any class of our common stock.

Preferred Stock

Our charter authorizes our Board of Directors to provide for the issuance of shares of preferred stock in one or more series.series without further authorization from stockholders. Prior to issuance of shares of each series, our Board of Directors is required by the DGCL and our charter to fix the designation, powers, preferences and rights of the shares of such series and the qualifications, limitations or restrictions thereof.  Thus, our Board

Warrants

We may issue warrants to purchase shares of Directors could authorizecommon stock or shares of preferred stock. We will issue warrants under one or more warrant agreements between us and a warrant agent we will name in the issuanceapplicable prospectus supplement.

The prospectus supplement relating to any warrants we are offering will include specific terms relating to the offering. These terms will include some or all of the following:

Rights

We may issue rights upon liquidation or with terms and conditions that could havefor the effectpurchase of delaying, deferring or preventing a transaction or a change of control of our company that might involve a premium price for holdersshares of our common stock or otherwiseshares of our preferred stock. Each series of rights will be issued under a separate rights agreement which we will enter into with a bank or trust company, as rights agent, all as set forth in the applicable prospectus supplement. 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 with any holders of rights certificates or beneficial owners of rights. We will file the rights agreement and the rights certificates relating to each series of rights with the SEC and incorporate them by reference as an exhibit to the registration statement of which this prospectus is a part on or before the time we issue a series of rights.

The applicable prospectus supplement will describe the terms of any rights we issue, including as applicable:

Rights will be exercisable for U.S. dollars only and will be in their best interests.registered form only.

Units

We may issue securities in units, each consisting of two or more types of securities. For example, we might issue units consisting of a combination of common stock and warrants to purchase common stock. If we issue units, the prospectus supplement relating to the units will contain information with regard to each of the securities that is a component of the units. In addition, the prospectus supplement relating to the units will describe the terms of any units we issue, including as applicable:

Anti-Takeover Provisions of Delaware Law and Our Governing Documents

Delaware Law

We are subject to Section 203 of the DGCL (“Section 203”). In general, Section 203 prohibits a publicly held Delaware corporation from engaging in “business combination” transactions with any “interested stockholder” for a period of three years following the time that the stockholder became an interested stockholder, unless:

Amendment of Certificate of Incorporation and Bylaws

Our charter may be amended by the affirmative vote of a majority of the aggregate number of shares of each class of our capital stock issued and outstanding after a resolution of our Board of Directors declaring the advisability of such amendment has been adopted in accordance with Delaware law. Our bylaws may be amended by the affirmative vote of a majority of the aggregate number of shares of each class of our capital stock issued and outstanding (and entitled to vote on the subject matter) present in person or represented by proxy at a meeting of stockholders provided that notice thereof is stated in the written notice of the meeting. Our bylaws may also be amended by a majority of the Board of Directors in accordance with Delaware law and our charter, except that certain sections of our bylaws (including but not limited to certain provisions regarding special meetings, voting, officers, and approval of securities issuances) require either the affirmative vote oftwo-thirds of the persons then serving as directors on the Board of Directors or our stockholders.

Forum Selection

Unless the Board of Directors acting on behalf of the Company selects an alternative forum, the Court of Chancery of the State of Delaware (or, if the Court of Chancery does not have jurisdiction, another state court located within the State of Delaware or, if no court located within the State of Delaware has jurisdiction, the federal district court for the District of Delaware) shall be the sole and exclusive forum for (i) any derivative action or proceeding brought on behalf of the Company, (ii) any action asserting a claim of breach of a fiduciary duty owed by any of our directors, officers or other employees to the Company or our stockholders, (iii) any action asserting a claim against the Company or any of our directors, officers or other employees arising pursuant to any provision of the DGCL, our charter or our bylaws or (iv) any action asserting a claim against the Company or any of our directors, officers or other employees governed by the internal affairs doctrine of the State of Delaware, in all cases subject to the court’s having personal jurisdiction over all indispensible parties named as defendants.

If any action the subject matter of which is within the scope of the immediately preceding paragraph is filed in a court other than a court located within the State of Delaware in the name of any stockholder, such stockholder will be deemed to have consented to (i) the personal jurisdiction of the state and federal courts located within the State of Delaware in connection with any action brought in any such court to enforce the exclusive forum provision (an “Enforcement Action”) and (ii) having service of process made upon such stockholder in any such Enforcement Action by service upon such stockholder’s counsel in the action outside of the State of Delaware as agent for such stockholder.

Stock Exchange Listing

Our common stock trades on the NASDAQThe Nasdaq Capital Market under the symbol “BIOL.”

Transfer Agent and Registrar

The transfer agent and registrar for our common stock is Computershare Trust Company, N.A.

This prospectus coversis part of a registration statement that provides that we may issue debt securities from time to time in one or more series under one or more indentures, in each case with the same or various maturities, at par or at a discount. Unless otherwise indicated in a prospectus supplement, we may issue additional debt securities of a particular series without the consent of the holders of the debt securities of such series outstanding at the time of the issuance. Any such additional debt securities, together with all other outstanding debt securities of that series, will constitute a single series of debt securities under the applicable indenture.

We intend to disclose any restrictive covenants for any issuance or series of debt securities in the applicable prospectus supplement.

PLAN OF DISTRIBUTION

We may sell the securities offered through this prospectus in one or more of the following ways (or in any combination) from time to time:

If underwriters or dealers are used in the sale, the securities will be acquired by the underwriters or dealers for their own account and may be resold from time to time in one or more transactions, including:

The prospectus supplement will include the following information:

Sale Through Underwriters or Dealers

If underwriters are used in the sale of any securities, the underwriters will acquire the securities for their own account, including through underwriting, purchase, security lending or repurchase agreements with us. The underwriters may resell the securities from time to time in one or more transactions, including negotiated transactions. Underwriters may sell the securities in order to facilitate transactions in any of our other securities (described in this prospectus or otherwise), including other public or private transactions and short sales. Underwriters may offer securities to the public either through underwriting syndicates represented by one or more managing underwriters or directly by one or more firms acting as underwriters. Unless otherwise indicated in the prospectus supplement, the obligations of the underwriters to purchase the securities will be subject to certain conditions, and the underwriters will be obligated to purchase all the offered securities if they purchase any of them. The underwriters may change from time to time any initial public offering price and any discounts or concessions allowed or reallowed or paid to dealers. The prospectus supplement will include the names of the principal underwriters, the respective amount of securities underwritten, the nature of the obligation of the underwriters to take the securities and the nature of any material relationship between an underwriter and us.

If dealers are used in the sale of securities offered through this prospectus, we will sell the securities to them as principals. They may then resell those securities to the public at varying prices determined by the dealers at the time of resale. The prospectus supplement will include the names of the dealers and the terms of the transaction.

We may authorize underwriters, dealers or agents to solicit offers by certain purchasers to purchase our securities from us at the public offering price set forth in the prospectus supplement pursuant to delayed delivery contracts providing for payment and delivery on a specified date in the future. The contracts will be subject to those conditions set forth in the prospectus supplement, and the prospectus supplement will set forth any commissions paid for solicitation of these contracts.

Underwriters, dealers and agents may contract for or otherwise be entitled to indemnification by us against certain civil liabilities, including liabilities under the Securities Act, or to contribution with respect to payments made by the underwriters, dealers or agents, under agreements between us on one hand, and the underwriters, dealers and agents, on the other hand.

We may grant underwriters who participate in the distribution of our securities an option to purchase additional securities to cover over-allotments, if any, in connection with the distribution.

Underwriters, dealers, or agents may receive compensation in the form of discounts, concessions or commissions from us or our purchasers, as their agents in connection with the sale of our securities. These underwriters, dealers or agents may be considered to be underwriters under the Securities Act. As a result, discounts, commissions or profits on resale received by the underwriters, dealers or agents may be treated as underwriting discounts and commissions. The prospectus supplement for any securities offered by us will identify any such underwriter, dealer or agent and describe any compensation received by them from us. Any public offering price and any discounts or concessions allowed orre-allowed or paid to dealers may be changed from time to time.

Underwriters, broker-dealers or agents who may become involved in the sale of 11,990,271 sharesour securities may engage in transactions with and perform other services for us for which they receive compensation.

Direct Sales and Sales Through Agents

We may sell the securities offered through this prospectus directly. In this case, no underwriters or agents would be involved. Such securities may also be sold through agents designated from time to time. The prospectus supplement will name any agent involved in the offer or sale of common stock, including 3,925,871 sharesthe offered securities and will describe any commissions payable to the agent by us. Unless otherwise indicated in the prospectus supplement, any agent will agree to use its reasonable best efforts to solicit purchases for the period of its appointment.

We may sell the securities directly to institutional investors or others who may be deemed to be underwriters within the meaning of the Securities Act, with respect to any sale of those securities.

At-the-Market Offerings

To the extent that we make sales through one or more underwriters or agents inat-the-market offerings, we will do so pursuant to the terms of a sales agency financing agreement or otherat-the-market offering arrangement between us, on one hand, and the underwriters or agents, on the other. If we engage inat-the-market sales pursuant to any such agreement, we will issue and sell our securities through one or more underwriters or agents, which may act on an agency basis or a principal basis. During the term of any such agreement, we may sell securities on a daily basis in exchange transactions or otherwise as we agree with the underwriters or agents. Any such agreement will provide that any securities sold will be sold at prices related to the then prevailing market prices for our securities. Therefore, exact figures regarding proceeds that will be raised or commissions to be paid cannot be determined at this time. Pursuant to the terms of the agreement, we may agree to sell, and the relevant underwriters or agents may agree to solicit offers to purchase blocks of our common stock thator other securities. The terms of any such agreement will be set forth in more detail in the prospectus supplement.

Market Making, Stabilization and Other Transactions

In connection with an offering through underwriters, an underwriter may, to the extent permitted by applicable rules and regulations, purchase and sell securities in the open market. These transactions, to the extent permitted by applicable rules and regulations, may include short sales, stabilizing transactions and purchases to cover positions created by short sales. Short sales involve the sale by the underwriters of a greater number of securities than they are required to purchase in the offering. “Covered” short sales are short sales made in an amount not greater than the underwriters’ option to purchase additional securities from us in the offering, if any. If the underwriters have an over-allotment option to purchase additional securities from us, the underwriters may consider, among other things, the price of securities available for purchase in the open market as compared to the price at which they

may purchase securities through the over-allotment option. “Naked” short sales, which may be issued uponprohibited or restricted by applicable rules and regulations, are any sales in excess of such option or where the exerciseunderwriters do not have an over-allotment option. The underwriters must close out any naked short position by purchasing securities in the open market. A naked short position is more likely to be created if the underwriters are concerned that there may be downward pressure on the price of warrants, issuedthe securities in the open market after pricing that could adversely affect investors who purchase in the offering.

Accordingly, to cover these short positions or to otherwise stabilize or maintain the price of the securities, the underwriters may bid for or purchase securities in the open market and may impose penalty bids. If penalty bids are imposed, selling stockholders namedconcessions allowed to syndicate members or other broker-dealers participating in this prospectusthe offering are reclaimed if securities previously distributed in the offering are repurchased, whether in connection with our previously disclosed private placement.stabilization transactions or otherwise. The selling stockholders are not requiredeffect of these transactions may be to offer anystabilize or maintain the market price of the sharessecurities at a level above that which might otherwise prevail in the open market. The imposition of a penalty bid may also affect the price of the securities to the extent that it discourages resale of the securities. The magnitude or effect of any stabilization or other transactions is uncertain.

Derivative Transactions and Hedging

We, the underwriters or other agents may engage in derivative transactions involving the securities. These derivatives may consist of short sale transactions and other hedging activities. The underwriters or agents may acquire a long or short position in the securities, hold or resell securities acquired and purchase options or futures on the securities and other derivative instruments with returns linked to or related to changes in the price of the securities. In order to facilitate these derivative transactions, we may enter into security lending or repurchase agreements with the underwriters or agents. The underwriters or agents may effect the derivative transactions through sales of the securities to the public, including short sales, or by lending the securities in order to facilitate short sale transactions by others. The underwriters or agents may also use the securities purchased or borrowed from us or others (or, in the case of derivatives, securities received from us in settlement of those derivatives) to directly or indirectly settle sales of the securities or close out any related open borrowings of the securities.

Trading Market and Listing of Securities

Any common stock sold or resold pursuant to a prospectus supplement will be listed on The Nasdaq Capital Market or on such other national securities exchange as our common stock covered by this prospectus for resale.  Since the selling stockholders may sell all, some or none of their shares, andthen be listed. The securities other than common stock may or may not exercisebe listed on a national securities exchange. It is possible that one or more underwriters may make a market in a class or series of securities, but the underwriters will not be obligated to do so and may discontinue any or allmarket making at any time without notice. We cannot give any assurance as to the liquidity of the warrants, we cannot estimate the aggregate number of shares that the selling stockholders will offer pursuant to this prospectus or that the selling stockholders will own upon completiontrading market for any of the offering to which this prospectus relates.securities.

General Information about additional selling stockholders

Agents, underwriters, and dealers may be set forth in a prospectus supplement, in a post-effective amendmententitled, under agreements entered into with us, to indemnification by us against certain liabilities, including liabilities under the Securities Act.

LEGAL MATTERS

Sidley Austin LLP will pass upon the validity of the securities being registered by the registration statement of which this prospectus formsis a partpart. Michael A. Gordon, a stockholder of the Company, is a partner at such firm. As of July 31, 2019, Mr. Gordon beneficially owned securities representing less than one percent of the outstanding common stock of the Company. Additional legal matters may be passed upon for us or in filingsany underwriters, dealers or agents, by counsel that we make with the SEC under the Exchange Act, which are incorporated by reference in this prospectus.

Each selling stockholder that sells shares of common stock pursuant to this prospectus may be deemed to be an “underwriter” within the meaning of the Securities Act.  Any commissions received by a broker or dealer in connection with resales of our common stock may be deemed to be underwriting commissions or discounts under the Securities Act.

The following table sets forth information with respect to our common stock beneficially owned by the selling stockholders as of July 21, 2017:

USE OF PROCEEDS

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 respective accounts.  We will not receive any of the proceeds from these sales, if any.  A portion of the shares covered by this prospectus may be issued upon exercise of warrants to purchase our common stock.  Upon any exercise of the warrants, the selling stockholder would pay us the exercise price of the warrants.  Any such proceeds would be used for working capital, including but not limited to new product development, launch and subsequent scale-up, as well as general corporate purposes.  We will pay all of the fees and expenses incurred by us in connection with this registration.  We will not be responsible for fees and expenses incurred by the selling stockholders or any underwriting discounts or agent’s commissions.

PLAN OF DISTRIBUTION

The selling stockholders and any of their pledgees, assignees and successors-in-interest may, from time to time, sell any or all of the shares of our common stock beneficially owned by them and offered hereby directly or through one or more underwriters, broker-dealers or agents.  The selling stockholders will be responsible for any underwriting discounts or agent’s commissions.  The common stock may be sold in one or more transactions at fixed prices, at prevailing market prices at the time of the sale, at varying prices determined at the time of sale, or at negotiated prices.  The selling stockholders may use any one or more of the following methods when selling shares:

The selling stockholders also may sell shares under Rule 144 promulgated under the Securities Act rather than under this prospectus or any related prospectus supplement.

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

The selling stockholders and any broker-dealers or agents that are involved in selling the shares may be deemed to be “underwriters” within the meaning of the Securities Act in connection with such sales.  In such event, any compensation received by such broker-dealers or agents and any profit on the resale of the shares purchased by them may be deemed to be underwriting commissions or discounts under the Securities Act.  While neither we nor any selling stockholder can presently estimate the amount of such compensation, in compliance with the guidelines of the Financial Industry Regulatory Authority, Inc. (“FINRA”), the aggregate maximum discount, commission, agency fees or other items constituting underwriting compensation to be received by any FINRA member or independent broker-dealer will not exceed 8% of any offering pursuant to this prospectus and any related prospectus supplement.  However, it is anticipated that the maximum commission or discount to be received in any particular offering of securities will be less than this amount.

Because selling stockholders may be deemed to be “underwriters” within the meaning of Section 2(a)(11) of the Securities Act, the selling stockholders will be subject to the prospectus delivery requirements of the Securities Act, which may include delivery through the facilities of NASDAQ pursuant to Rule 153 under the Securities Act.

We have agreed to indemnify certain of the selling stockholders against certain liabilities, including liabilities arising under the Securities Act.  The selling stockholders may agree to indemnify any agent, dealer or broker-dealer that participates in transactions involving sales of shares of common stock against certain liabilities, including liabilities arising under the Securities Act.

The resale securities will be sold only through registered or licensed brokers or dealers if required under applicable state securities laws.  In addition, in certain states, the resale securities covered hereby may not be sold unless they have been registered or qualified for salename in the applicable state or an exemption from the registration or qualification requirement is available and is complied with.prospectus supplement.

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

Each selling stockholder has informed the Company that it does not have any written or oral agreement or understanding, directly or indirectly, with any person to distribute the shares of our common stock covered by this prospectus.  Upon being notified by a selling stockholder that any material arrangement has been entered into with a broker-dealer or underwriter for the sale of shares of common stock through a block trade, special offering, exchange distribution or secondary distribution or a purchase by a broker or dealer, we will file a supplement to this prospectus, if required, pursuant to Rule 424(b) under the Securities Act, disclosing (i) the name of each such selling stockholder and of the participating broker-dealer(s) or underwriter(s), (ii) the number of shares of common stock involved, (iii) the price at which such shares were or will be sold, (iv) the commissions paid or to be paid or discounts or concessions allowed to such broker-dealer(s) or underwriter(s), where applicable, (v) that, as applicable, such broker-dealer(s) or underwriter(s) did not conduct any investigation to verify the information set out or incorporated by reference in this prospectus and (vi) other facts material to the transaction.

With certain limited exceptions, we have agreed to use commercially reasonable efforts to keep the registration statement of which this prospectus forms a part effective until the later of (i) the date by which all of the shares of common stock covered by this prospectus may be sold without volume or manner of sale restrictions which may be applicable to affiliates under Rule 144, (ii) all of the shares covered by this prospectus have been sold, or (iii) April 18, 2019.  There can be no assurance that the selling stockholders will sell any or all of the shares of common stock registered pursuant to the registration statement, of which this prospectus or any related prospectus supplement forms a part.

LEGAL MATTERS

The legality of the issuance of the shares of our common stock offered hereby is being passed upon by Sidley Austin LLP, Chicago, Illinois.  If counsel for any selling stockholder or underwriter passes on legal matters in connection with an offering of the common stock described in this prospectus, we will name that counsel in the prospectus supplement to that offering.

EXPERTS

The consolidated financial statements and schedule of Biolase,BIOLASE, Inc. as of December 31, 20162018 and 20152017 and for each of the three years in the period ended December 31, 20162018 incorporated by reference into this prospectus from our Annual Reporthave been so incorporated in reliance upon the report of BDO USA, LLP, an independent registered accounting firm (the report on Form 10‑K for the fiscal year ended December 31, 2016, filed with the SEC on March 10, 2017, whichfinancial statements contains an explanatory paragraph regarding the Company’s ability to continue as a going concern, have been so incorporated in reliance upon the reports of BDO USA, LLP, an independent registered accounting firm,concern), incorporated herein by reference, given upon the authority of said firm as experts in accounting and auditing.

INCORPORATION OF CERTAIN INFORMATION BY REFERENCE

The SEC allows us to incorporate by reference into this prospectus the information contained in other documents we file with the SEC, which means that we can disclose important information to you by referring you to those documents. Any statement contained in any document incorporated or deemed to be incorporated by reference herein shall be deemed to be modified or superseded, for purposes of this prospectus, to the extent that a statement contained in or omitted from this prospectus, or in any other subsequently filed document that also is or is deemed to be incorporated by reference herein, modifies or supersedes such statement. Any such statement so modified or superseded shall not be deemed, except as so modified or superseded, to constitute a part of this prospectus. We incorporate by reference the documents listed below which have been filed by us and any future filings we make with the SEC under Sections 13(a), 13(c), 14 or 15(d) of the Exchange Act (other than current reports furnished under Item 2.02 or Item 7.01 of Form8-K and exhibits filed on such form that are related to such items unless such Form8-K expressly provides to the contrary) subsequent to the date of the initial filing of the registration statement of which this prospectus forms a part until the offering of the securities covered by this prospectus is completed:

Upon written or oral request, we will provide without charge to each person to whom a copy of the prospectus is delivered a copy of the documents incorporated by reference herein (other than exhibits to such documents unless such exhibits are specifically incorporated by reference herein). You may request a copy of these filings, at no cost, by writing or telephoning us at the following address: Biolase,BIOLASE, Inc., 4 Cromwell, Irvine, California 92618, Attention: Investor Relations, telephone:(949) 361-1200.

WHERE YOU CAN FIND MORE INFORMATION

We are subject to the informational requirements of the Exchange Act and in accordance therewith file reports, proxy statements and other information with the SEC. Our filings are available to the public over the Internet at the SEC’s website atwww.sec.gov, as well as at our website atwww.biolase.com.

You mayInformation on any BIOLASE, Inc. website, any subsection, page, or other subdivision of any BIOLASE, Inc. website, or any website linked to by content on any BIOLASE, Inc. website, is not part of this prospectus and you should not rely on that information unless that information is also read and copy, at prescribed rates, any document we file with the SEC at the Public Reference Room of the SEC located at 100 F Street, N.E., Washington, D.C. 20549.  Please call the SEC at (800) SEC-0330 for further information on the SEC’s Public Reference Room.in this prospectus or incorporated by reference in this prospectus.

PART II

INFORMATION NOT REQUIRED IN PROSPECTUS

Item 14. Other Expenses of Issuance and Distribution.

The following table sets forth variousthe estimated costs and expenses, other than underwriting discounts and commissions, payable by us in connection with the sale and distributionoffering of the shares of our common stocksecurities being registered. All of the amounts shown are estimates except for the SEC Registration Fee.

Item 16.Exhibits.

The following documents are filed herewith (unless otherwise indicated) and made a part ofas exhibits to this registration statement.statement, including those exhibits incorporated herein by reference to one of our prior filings under the Securities Act or the Exchange Act.

(2) That, for the purpose of determining any liability under the Securities Act of 1933, 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.

(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

(4) That, for the purpose of determining liability under the Securities Act of 1933 to any purchaser:

(A)(i) 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 thisthe registration statement; and

(B)(ii) 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 of 1933 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,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 thisthe 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 of 1933 to any purchaser in the initial distribution of the 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.

The undersigned registrant hereby undertakes that, for purposes of determining any liability under the Securities Act of 1933, each filing of the registrant’s annual report pursuant to Section 13(a) or Section 15(d) of the Securities Exchange Act of 1934 (and, where applicable, each filing of an employee benefit plan’s annual report pursuant to Section 15(d) of the Securities Exchange Act)Act of 1934) that is incorporated by reference in this registration statement shall be deemed to be a new registration statement relating to the securities offered herein, and the offering of such securities at that time shall be deemed to be the initial bona fide offering thereof.

Insofar as indemnification for liabilities arising under the Securities Act of 1933, 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 of 1933 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 Securities Act of 1933 and will be governed by the final adjudication of such issue.

The undersigned registrant hereby undertakes that:

(1)  For purposes of determining any liability under the Securities Act of 1933, 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 (“Act”) in accordance with the rules and regulations prescribed by the Commission under section 305(b)(2) of 1933, each post-effective amendment that contains a form 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-3II-4

SIGNATURES

Pursuant to the requirements of the Securities Act of 1933, the registrant certifies that it has reasonable grounds to believe that it meets all of the requirements for filing onForm S‑3S-3 and has duly caused this registration statement to be signed on its behalf by the undersigned, thereunto duly authorized in the City of Irvine, State of California, on August 22, 2017.9, 2019.