QDEL QuidelOrtho Corporation

As filed with the Securities and Exchange Commission on November 19, 2024.

Registration No. 333-   

UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

WASHINGTON, D.C. 20549

FORM S-3

REGISTRATION STATEMENT

UNDER

THE SECURITIES ACT OF 1933

QUIDELORTHO CORPORATION

(Exact name of Registrant as specified in its charter)

9975 Summers Ridge Road

San Diego, California 92121

(858) 552-1100

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

Michelle A. Hodges

Chief Legal Officer

QuidelOrtho Corporation

9975 Summers Ridge Road

San Diego, California 92121

(858) 552-1100

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

Copies to:

Ryan A. Murr

Branden C. Berns

Gibson, Dunn & Crutcher LLP

One Embarcadero Center, Suite 2600

San Francisco, CA 94111-3715

(415) 393-8200

Approximate date of commencement of proposed sale to the public:

From time to time after this registration statement becomes effective.

If the only securities being registered on this Form 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 Form 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 Form 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, a non-accelerated filer, a smaller reporting company or an emerging growth company. See the definitions of “large accelerated filer,” “accelerated filer,” “smaller reporting company” and “emerging growth company” in Rule 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 new or revised financial accounting standards provided pursuant to Section 7(a)(2)(B) of the Securities Act. ☐

PROSPECTUS

8,260,183 Shares

QUIDELORTHO CORPORATION

Common Stock

This prospectus covers the offer and resale by the selling stockholder identified in this prospectus of up to an aggregate of 8,260,183 shares of our common stock, par value $0.001 per share. We are registering these securities for resale pursuant to the selling stockholder’s registration rights under that certain principal stockholders agreement, dated December 22, 2021, among us, the selling stockholder and other parties party thereto.

We are not offering or selling any shares of common stock under this prospectus and we will not receive any proceeds from the sale of the common stock by the selling stockholder.

The selling stockholder may offer and sell the shares of common stock at fixed prices, at prevailing market prices at the time of sale, at prices related to the prevailing market price, or at varying prices determined at the time of sale or at negotiated prices. The selling stockholder may sell the shares to or through underwriters, broker-dealers or agents, who may receive compensation in the form of discounts, concessions or commissions from the selling stockholder, the purchasers of the shares, or both.

We are paying the cost of registering the shares of common stock covered by this prospectus as well as various related expenses and transfer taxes. We provide more information about how the selling stockholder may sell or otherwise dispose of its shares of common stock in the section titled “Plan of Distribution” beginning on page 14 of this prospectus. The selling stockholder will bear any brokerage costs or underwriting discounts and commissions incurred by the selling stockholder in disposing of its shares of common stock, as described in more detail in the section titled “Plan of Distribution—Expenses of this Offering.”

Our common stock is listed on The Nasdaq Global Select Market (“Nasdaq”) under the symbol “QDEL.” On November 18, 2024, the last reported sales price of a share of our common stock on Nasdaq was $37.39.

Investing in our common stock involves a high degree of risk. Please read the section titled “Risk Factors” beginning on page 8 of this prospectus as well as the risk factors and other information contained in the applicable prospectus supplement, any related free writing prospectus, and in the documents we incorporate by reference into this prospectus or applicable prospectus supplement. See “Where You Can Find More Information.”

NEITHER THE SECURITIES AND EXCHANGE COMMISSION NOR ANY STATE SECURITIES COMMISSION HAS APPROVED OR DISAPPROVED OF THESE SECURITIES OR DETERMINED IF THIS PROSPECTUS IS TRUTHFUL OR COMPLETE. ANY REPRESENTATION TO THE CONTRARY IS A CRIMINAL OFFENSE.

Prospectus dated November 19, 2024

TABLE OF CONTENTS

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ABOUT THIS PROSPECTUS

This prospectus is part of an “automatic shelf” registration statement on Form S-3 that we filed with the Securities and Exchange Commission (the “SEC”) as a “well-known seasoned issuer” as defined in Rule 405 under the Securities Act of 1933, as amended (the “Securities Act”), using the “shelf” registration process. Under this shelf registration process, the selling stockholder named in this prospectus may offer and sell shares of the common stock described in this prospectus from time to time in one or more offerings or resales. This prospectus provides you with a general description of the shares of common stock the selling stockholder may offer. We may provide a prospectus supplement containing specific information about the terms of a particular offering by the selling stockholder. Any accompanying prospectus supplement or any related free writing prospectus may also add, update or change information contained in this prospectus or in any documents incorporated by reference into this prospectus. To the extent there are inconsistencies between this prospectus and the accompanying prospectus supplement, you should rely on the information in the accompanying prospectus supplement. You should read this prospectus, any accompanying prospectus supplement and any related free writing prospectus, together with the information incorporated herein and therein by reference as described under the section titled “Incorporation by Reference,” before investing in the common stock offered.

You should rely only on the information contained in or incorporated by reference into this prospectus, any accompanying prospectus supplement and any applicable free writing prospectus. Neither we nor the selling stockholder has authorized anyone to provide you with different information. This document may only be used where it is legal to sell our common stock. You should not assume that the information contained in this prospectus, any prospectus supplement, any applicable free writing prospectus or the documents incorporated by reference, is accurate as of any date other than the dates of those documents regardless of the time of delivery of the prospectus or prospectus supplement or any sale of the common stock.

For investors outside the United States: Neither we nor the selling stockholder have done or will do anything that would permit this offering, or possession or distribution of this prospectus, any prospectus supplement or free writing prospectus, in any jurisdiction where action for that purpose is required other than in the United States. Persons outside the United States who come into possession of this prospectus, any applicable prospectus supplement or free writing prospectus must inform themselves about, and observe any restrictions relating to, the offering of the common stock and the distribution of this prospectus outside of the United States.

In this prospectus, unless expressly indicated or the context otherwise requires, references to “we,” “our,” “us,” “the Company,” and “our Company” refer to QuidelOrtho Corporation, a Delaware corporation, and its consolidated subsidiaries.

All references to “this prospectus” refer to this prospectus and any accompanying prospectus supplement, including the documents incorporated by reference herein and therein, unless the context otherwise requires.

WHERE YOU CAN FIND MORE INFORMATION

We file annual, quarterly and current reports and other information with the SEC. Our filings with the SEC are available to the public on the SEC’s website at www.sec.gov. Those filings are also available to the public on, or accessible through, our website under the heading “Investor Relations” at www.quidelortho.com. The information we file with the SEC (except as described below under the section titled “Incorporation by Reference”) or contained on or accessible through our corporate website or any other website that we may maintain is not part of, and is not incorporated by reference into, this prospectus and you should not rely on that information when making a decision to invest in our common stock. Inclusion of our website address in this prospectus is an inactive textual reference only.

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INCORPORATION BY REFERENCE

The rules of the SEC allow us to incorporate by reference information we file with the SEC. This means that we are disclosing important information to you by referring to other documents. The information incorporated by reference is considered to be part of this prospectus. To the extent there are inconsistencies between the information contained in this prospectus and the information contained in the documents filed with the SEC prior to the date of this prospectus and incorporated by reference, the information in this prospectus shall be deemed to supersede the information in such incorporated documents. We incorporate by reference the documents listed below (other than any portions thereof which under the Securities Exchange Act of 1934, as amended (the “Exchange Act”) and applicable SEC rules are not deemed “filed” under the Exchange Act, such as any information furnished under Item 2.02 or Item 7.01 of any Current Report on Form 8-K and exhibits filed on such form that are related to such items):

All documents filed by us pursuant to Section 13(a), 13(c), 14 or 15(d) of the Exchange Act on or after the date of this prospectus and prior to the termination of the offering of the securities to which this prospectus relates shall be deemed to be incorporated by reference herein and to be a part of this prospectus from the date of filing of such documents (other than any portions thereof, which under the Exchange Act and applicable SEC rules, are not deemed “filed” under the Exchange Act, such as any information furnished under Item 2.02 or Item 7.01 of any Current Report on Form 8-K and exhibits filed on such form that are related to such items).

Subsequent information that we file with the SEC will automatically update and supersede this information to the extent there are inconsistencies. Without limiting the foregoing, if we have incorporated by reference any statement or information in this prospectus and we subsequently modify that statement or information with information contained in or incorporated by reference into this prospectus, the statement or information previously incorporated in this prospectus is also modified or superseded in the same manner. We will provide without charge to each person to whom a copy of this prospectus has been delivered, a copy of any and all of these filings. You may request a copy of these filings by writing to us at:

Investor Relations

9975 Summers Ridge Road

San Diego, California 92121

e-mail: IR@quidelortho.com

Exhibits to any documents incorporated by reference in this prospectus will not be sent, however, unless those exhibits have been specifically referenced in this prospectus.

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SPECIAL NOTE REGARDING FORWARD-LOOKING STATEMENTS

Statements made herein or incorporated by reference in this prospectus and any accompanying prospectus supplement contain forward-looking statements within the meaning of the Private Securities Litigation Reform Act of 1995, Section 27A of the Securities Act and Section 21E of the Exchange Act. These statements are any statement contained or incorporated by reference herein that is not strictly historical, including, but not limited to, statements regarding our commercial, integration and other strategic goals, our cost-savings initiatives, industry prospects, our expected results of operations or financial position, and future plans, objectives, strategies, expectations and intentions. Without limiting the foregoing, the words “may,” “will,” “would,” “should,” “might,” “expect,” “anticipate,” “believe,” “estimate,” “plan,” “intend,” “goal,” “project,” “strategy,” “future,” “continue” or similar words, expressions or the negative of such terms or other comparable terminology are intended to identify forward-looking statements. Such statements are based on the beliefs and expectations of our management as of the date of this prospectus and any accompanying prospectus supplement and are subject to significant known and unknown risks and uncertainties.

As you read and consider this prospectus, any accompanying prospectus supplement and the information incorporated by reference herein or therein, you should understand that these forward-looking statements are not guarantees of performance or results. You should not rely on forward-looking statements as predictions of future events because these statements are based on assumptions that may not come true and are speculative by their nature. Although we believe that these forward-looking statements are based on reasonable assumptions at the time they are made, you should be aware that many factors could affect our business, financial condition, results of operations, cash flows and prospects, and therefore actual results or outcomes may differ significantly from those set forth or implied in the forward-looking statements. The following factors and additional risks and uncertainties not presently known to us or that we currently deem immaterial could cause actual results to differ from those set forth or implied in the forward-looking statements:

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These cautionary statements should not be construed by you to be exhaustive and speak only as of the date the statements are made. We undertake no obligation to update any of the forward-looking information or time-sensitive information included in this prospectus and any accompanying prospectus supplement, whether as a result of new information, future events, changed expectations or otherwise, except as required by law. For further discussion of the risks relating to our business, see the section titled “Risk Factors” in the documents incorporated by reference herein.

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RISK FACTORS

Investing in our common stock involves a high degree of risk. You should carefully consider the risks and uncertainties described in this prospectus and any accompanying prospectus supplement, including, without limitation, the risk factors set forth in our Annual Report on Form 10-K for the fiscal year ended December 31, 2023, as such risk factors may be updated in our other filings with the SEC pursuant to Section 13(a), 13(c), 14, or 15(d) of the Exchange Act, and the risk factors described in any other filings we make with the SEC from time to time, which are incorporated by reference herein, before making an investment decision pursuant to this prospectus and any accompanying prospectus supplement relating to a specific offering.

Our business, financial condition, results of operations, cash flows and prospects, and your investment in the offered securities, could be materially and adversely affected by any or all of these risks or by additional risks and uncertainties not presently known to us or that we currently deem immaterial that may adversely affect us in the future.

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USE OF PROCEEDS

Any shares of common stock offered under this prospectus will be offered by the selling stockholder, and the selling stockholder will receive all of the net proceeds from any sale of shares of common stock under this prospectus. We are not offering any shares of common stock under this prospectus and will not receive any proceeds from any sale of shares of common stock by the selling stockholder.

We are paying the cost of registering the shares of common stock covered by this prospectus as well as various related expenses and transfer taxes. The selling stockholder will bear any brokerage costs or underwriting discounts and commissions incurred by the selling stockholder in disposing of its shares of common stock, as described in more detail in the section titled “Plan of Distribution—Expenses of this Offering.”

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SELLING STOCKHOLDER

We are registering the resale of 8,260,183 shares of common stock to permit the selling stockholder to resell such shares, as set forth in the table below, in the manner contemplated under the section titled “Plan of Distribution” in this prospectus. The shares covered by this prospectus may be offered from time to time by the selling stockholder.

The selling stockholder may sell some, all or none of its shares of common stock covered by this prospectus from time to time. We do not know how long the selling stockholder will hold its shares before selling them. The selling stockholder may, from time to time, sell, transfer or otherwise dispose of any or all of the shares on any stock exchange, market or trading facility on which our common stock is traded or in private transactions. As a result, we cannot estimate the number of shares of common stock covered by this prospectus the selling stockholder will own in the future.

The table below sets forth the number of shares of our common stock that the selling stockholder may offer and sell pursuant to this prospectus, as well as the selling stockholder’s beneficial ownership of our common stock prior to and following its sale of shares covered by this prospectus (assuming all shares covered by this prospectus are sold).

Beneficial ownership for the purposes of the following table is determined in accordance with the rules and regulations of the SEC. A person is a “beneficial owner” of a security if that person has or shares “voting power,” which includes the power to vote or to direct the voting of the security, or “investment power,” which includes the power to dispose of or to direct the disposition of the security, or has the right to acquire such powers within 60 days.

All information with respect to common stock ownership of the selling stockholder was furnished by the selling stockholder and is as of October 30, 2024, and assumes 67,256,717 shares of common stock outstanding as of October 30, 2024.

Accordingly, each of the foregoing entities may be deemed to share beneficial ownership of the securities held of record by Carlyle Partners VI Cayman Holdings, L.P. Each of them, other than Carlyle Partners VI Cayman Holdings, L.P., disclaims beneficial ownership of such securities. The address for each of TC Group Cayman Investment Holdings, L.P., TC Group Cayman Investment Holdings Sub L.P., TC Group VI Cayman, L.P. and Carlyle Partners VI Cayman Holdings, L.P. is c/o Walkers Corporate Limited, 190 Elgin Avenue, George Town, Grand Cayman KY1-9008, Cayman Islands. The address of each of the other entities named in this footnote is c/o The Carlyle Group Inc., 1001 Pennsylvania Avenue, NW, Suite 220 South, Washington, D.C. 20004.

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DESCRIPTION OF CAPITAL STOCK

General

The following information is a summary of the material terms of the capital stock of the Company and is subject to, and qualified in its entirety by reference to, the more complete descriptions of the Company’s capital stock in its Charter and its Bylaws, which are filed as Exhibit 4.1 and Exhibit 4.2 to the registration statement of which this prospectus forms a part.

Our authorized capital stock consists of 126,200,000 shares of common stock, par value $0.001 per share, and 5,000,000 shares of preferred stock, par value $0.001 per share. As of October 30, 2024, there were 67,256,717 shares of common stock and no shares of preferred stock outstanding.

Common Stock

The Charter authorizes the issuance of up to 126,200,000 shares of common stock. All outstanding shares of common stock are validly issued, fully paid and nonassessable.

Voting. Except as otherwise required by law (and subject to the rights of any other outstanding capital stock under the Charter), each outstanding share of common stock is entitled to vote on each matter on which our stockholders are entitled to vote, and each holder thereof is entitled to one vote for each share of common stock held by such holder. Common stockholders do not have cumulative voting rights.

Dividends. Common stockholders have the right to receive dividends when, as and if declared by the board of directors of the Company (the “Board”) from funds legally available therefor.

Special Meetings and Notice Procedures. The Bylaws provide that special meetings of stockholders may be called by stockholders of record, as of the record date fixed as provided therein, holding in the aggregate not less than 50% of the voting power of our issued and outstanding capital stock. In addition, the Bylaws establish an advance written notice procedure for stockholders seeking to nominate candidates for election to the Board or to propose matters to be acted upon at stockholders’ meetings. As a result, these provisions of the Bylaws may delay stockholder actions with respect to business combinations or a change in management and may make it more difficult for third parties to acquire control of the Company.

Advanced Notice Bylaws. For director nominations or other business to be properly brought before an annual meeting by a stockholder, such stockholder must generally provide notice to the Company no later than 90 days and no more than 120 days prior to the first anniversary of the date of the prior year’s annual meeting; provided, that if the date of the annual meeting is advanced by more than 30 days prior to or delayed by more than 60 days after the anniversary of the preceding year’s annual meeting, such notice must be delivered no more than 120 days prior to such annual meeting nor less than the later of (i) 90 days prior to such annual meeting and (ii) ten days after the day on which public disclosure of the date of such meeting is first made.

Exclusive Jurisdiction. The Bylaws provide that unless the Company selects or consents in writing to the selection of an alternative forum, (i) the sole and exclusive forum for any complaint by any current or former stockholder asserting any internal corporate claims, to the fullest extent permitted by law, and subject to applicable jurisdictional requirements, shall be the Court of Chancery of the State of Delaware (or, if the Court of Chancery does not have, or declines to accept, jurisdiction, another state court or a federal court located within the State of Delaware), and (ii) the sole and exclusive forum for any complaint by any current or former stockholder asserting a cause of action arising under the Securities Act, to the fullest extent permitted by law, shall be the federal district courts of the United States of America.

Delaware Anti-takeover Statute. The Company has opted out of Section 203 of the General Corporation Law of the State of Delaware (the “DGCL”), which is a statute that (if applicable) would have served to make certain types of unfriendly or hostile corporate takeovers, or other non-board approved transactions involving a corporation and one or more of its significant stockholders, more difficult.

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Other Rights. Common stockholders do not have any preemptive, subscription or conversion rights under the Charter.

Preferred Stock

Under the terms of the Charter, the Board is authorized to issue from time to time, without further vote or action by the stockholders, up to an aggregate of 5,000,000 shares of preferred stock in one or more series. The Board is authorized, within the limitations and restrictions stated in the Charter, to determine or alter the rights, preferences, privileges and restrictions granted to or imposed on any wholly unissued series of preferred shares, and the number of shares constituting such series and the designation thereof. No preferred shares are currently outstanding.

The Company currently has no plans to issue any shares of preferred stock, but the Company believes that the ability to issue shares of preferred stock without the expense and delay of a special stockholders’ meeting will provide the Company with increased flexibility in structuring possible future financings and acquisitions, and in meeting other corporate needs that might arise. The Board could issue shares of preferred stock having voting, dividend and liquidation rights superior to those of the shares of common stock, which could adversely affect the voting power of the common stockholders, including the loss of voting control to others, and delay, defer or prevent a change in control of the Company without further action by the stockholders. This could discourage an acquisition attempt or other transaction that stockholders might believe to be in their best interests or in which they might receive a premium for their stock over the then-market price of the stock.

If the Board were to issue a new series of preferred stock, the issuance of such shares could:

Registration Rights

Pursuant to a Principal Stockholders Agreement (the “Stockholders Agreement”), dated December 22, 2021, by and among Ortho, Quidel and Carlyle Partners VI Cayman Holdings, L.P. (the “Carlyle Investor”), the Carlyle Investor is entitled to demand and piggyback rights with respect to the registration under the Securities Act of shares of common stock held by the Carlyle Investor. In certain instances, the Carlyle Investor may cause the Company, at the Company’s expense, to file registration statements under the Securities Act covering resales of shares of common stock held by the Carlyle Investor or to piggyback on other registration statements in certain circumstances and subject to certain limitations. The Company will pay all expenses related to any demand, piggyback or Form S-3 registration, with the exception of underwriting discounts and commissions, which will be paid by the selling stockholder.

The Carlyle Investor’s demand rights (excluding rights with respect to “shelf” registrations) expire in the event that the Carlyle Investor owns less than 5% of the outstanding shares of common stock, and its other registration rights expire on a holder-by-holder basis when the Carlyle Investor or any permitted transferee thereof owns less than 1% of the outstanding shares of common stock, in each case, only if the Carlyle Investor or such permitted transferee can sell its shares of common stock without volume or manner of sale restrictions under Rule 144 under the Securities Act.

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Transfer Agent and Registrar

Computershare, Inc. serves as the transfer agent and registrar for the Company’s common stock.

Listing

The Company’s common stock is listed on Nasdaq under the symbol “QDEL.”

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PLAN OF DISTRIBUTION

Resales by Selling Stockholder

We are registering the shares of common stock covered by this prospectus on behalf of the selling stockholder pursuant to the terms of the Stockholders Agreement.

The selling stockholder may offer and sell the shares of common stock from time to time, either in increments or in a single transaction. The selling stockholder may also decide not to sell any or all the shares of common stock it is allowed to sell under this prospectus. The selling stockholder will act independently of us in making decisions with respect to the timing, manner and size of each sale. The selling stockholder is not restricted as to the price or prices at which it may sell its shares of common stock. Sales of such shares may have an adverse effect on the market price of the common stock. Moreover, it is possible that a significant number of shares of common stock could be sold at the same time, which may have an adverse effect on the market price of the common stock.

The term “selling stockholder” also includes persons who obtain common stock from the selling stockholder as a gift, on foreclosure of a pledge, in a distribution or dividend of assets by an entity to its equity holders or partners, as an assignee, transferee or other successor-in-interest, or in another private transaction.

Types of Sale Transactions

The selling stockholder may sell the shares of common stock offered by this prospectus from time to time at market prices prevailing at the time of sale, at prices related to such prevailing market prices, at negotiated prices, at fixed prices or at prices that may be subject to change. Sales of shares of our common stock by the selling stockholder may occur from time to time in one or more of the following types of transactions (which may involve crosses or block transactions):

The selling stockholder may enter into hedging transactions from time to time in which a selling stockholder may:

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The selling stockholder may use broker-dealers or other persons to sell its shares in transactions that may include one or more of the following:

A prospectus supplement or supplements (and any related free writing prospectus that we may authorize to be provided to you) will describe the terms of any offering of the securities, including, to the extent applicable:

Sales by the selling stockholder of the common stock offered by this prospectus may be made directly to investors or through securities firms acting as underwriters, brokers or dealers. Only firms named in an applicable prospectus supplement will be underwriters, brokers or dealers, as applicable, for the shares of our common stock offered by such prospectus supplement. When resales are to be made through a securities firm, the securities firm may be engaged to act as the selling stockholder’s agent in the resale of the shares of common stock by the selling stockholder, or the securities firm may purchase shares of our common stock from the selling stockholder as principal and thereafter resell those shares from time to time. The fees earned by or paid to the securities firm may be the normal stock exchange commission or negotiated commissions or underwriting discounts to the extent permissible. The securities firm may resell the securities through other securities dealers, and commissions or concessions to those other dealers may be allowed.

At any time a particular offer of the shares of our common stock covered by this prospectus is made, a prospectus supplement, if required, will be distributed which will set forth the aggregate amount of shares of common stock covered by this prospectus being offered and the terms of the offering, including the name or names of any underwriters, dealers, brokers or agents, any option under which underwriters may purchase additional shares of our common stock from the selling stockholder, any discounts, commissions, concessions and other items constituting compensation from the selling stockholder and any discounts, commissions or concessions allowed or reallowed or paid to dealers. Such prospectus supplement, and, if necessary, a post-effective amendment to the

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registration statement of which this prospectus is a part, will be filed with the SEC to reflect the disclosure of additional information with respect to the distribution of the shares of our common stock covered by this prospectus. Under the securities laws of some states, the shares of our common stock may be sold in such states only through registered or licensed brokers or dealers. In addition, in some states, the shares of our common stock may not be sold unless such shares have been registered or qualified for exemption from registration or qualification is available and is complied with.

The selling stockholder and any agent, broker or dealer that participates in sales of common stock offered by this prospectus may be deemed “underwriters” under the Securities Act, and any commissions or other consideration received by any agent, broker or dealer may be considered underwriting discounts or commissions under the Securities Act.

Instead of selling shares of common stock under this prospectus, the selling stockholder may:

In addition, the selling stockholder may elect to make a pro rata in-kind distribution of securities to its members, partners or stockholders pursuant to the registration statement of which this prospectus is a part by delivering a prospectus with a plan of distribution. Such members, partners or stockholders would thereby receive freely tradeable securities pursuant to the distribution through a registration statement. To the extent a distributee is an affiliate of ours (or to the extent otherwise required by law), we may, at our option, file a prospectus supplement in order to permit the distributees to use the prospectus to resell the securities acquired in the distribution.

Regulation M

We have informed the selling stockholder that the anti-manipulation provisions of Regulation M under the Exchange Act may apply to its sales of common stock.

Any underwriters or agents that are qualified market makers on Nasdaq may engage in passive market making transactions in the common stock on Nasdaq in accordance with Regulation M under the Exchange Act, during the business day prior to the pricing of an offering, before the commencement of offers or sales of the common stock. Passive market makers must comply with applicable volume and price limitations and must be identified as passive market makers. In general, a passive market maker must display its bid at a price not in excess of the highest independent bid for such security; if all independent bids are lowered below the passive market maker’s bid, however, the passive market maker’s bid must then be lowered when certain purchase limits are exceeded. Passive market making may stabilize the market price of the securities at a level above that which might otherwise prevail in the open market and, if commenced, may be discontinued at any time.

Expenses of this Offering

Except as may be otherwise provided in an applicable prospectus supplement, pursuant to the Stockholders Agreement, we have agreed to pay certain expenses incurred in connection with the registration and sale of the shares of common stock covered by this prospectus, including, among other things, all registration and filing fees (including SEC, Nasdaq, the Financial Industry Regulatory Authority (“FINRA”) and blue sky registration and filing fees), printing expenses, transfer taxes, expenses incurred in connection with promotional efforts or “roadshows,” the fees and disbursements of our outside counsel and independent accountants, and the fees and disbursements of counsel for the selling stockholder, but excluding underwriters’, brokers’ and dealers’ discounts and commissions applicable to shares sold for the account of the selling stockholder. 

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Indemnification

We have agreed pursuant to the Stockholders Agreement, to indemnify, and may agree to further indemnify in the future, in certain circumstances the selling stockholder against certain liabilities, including liabilities under the Securities Act. The selling stockholder has agreed pursuant to the Stockholders Agreement, to indemnify, and may agree to further indemnify in the future, us in certain circumstances against certain liabilities, including liabilities under the Securities Act.

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LEGAL MATTERS

The validity of the securities offered by this prospectus will be passed upon for us by Gibson, Dunn & Crutcher LLP, San Francisco, California. If certain legal matters in connection with an offering of the securities made by this prospectus and a related prospectus supplement are passed upon by counsel for the underwriters of such offering, such counsel will be named in the applicable prospectus supplement related to that offering.

EXPERTS

Ernst & Young LLP, independent registered public accounting firm, has audited our consolidated financial statements included in our Annual Report on Form 10-K for the year ended December 31, 2023, as amended, and the effectiveness of our internal control over financial reporting as of December 31, 2023, as set forth in their reports, which are incorporated by reference in this prospectus and elsewhere in the registration statement. Our financial statements are incorporated by reference in reliance on Ernst & Young LLP’s reports, given on their authority as experts in accounting and auditing.

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PART II

INFORMATION NOT REQUIRED IN PROSPECTUS

Item 14. Other Expenses of Issuance and Distribution

The following table sets forth all expenses, other than underwriting discounts and commissions, paid or payable by the registrant in connection with this offering. The selling stockholder will pay any underwriting, broker-dealer or agent discounts, concessions and commissions and expenses incurred by the selling stockholder for accounting, tax, and legal services and any other expenses incurred by the selling stockholder in disposing of the shares of common stock, unless otherwise agreed to by the registrant as described in the following sentence. The registrant will bear all other costs, fees and expenses incurred in connection with the registration and sale of the shares of common stock covered by this prospectus, including, among other things, all registration and filing fees (including SEC, Nasdaq, FINRA and blue sky registration and filing fees), printing expenses, expenses incurred in connection with promotional efforts or “roadshows,” the fees and disbursements of the registrant’s outside counsel and independent accountants, and the fees and disbursements of counsel for the selling stockholder. All amounts shown are estimates except for the SEC registration fee.

Item 15. Indemnification of Directors and Officers

The Company is incorporated under the laws of the State of Delaware. Section 145(a) of the DGCL authorizes a corporation to indemnify any person who was or is a party, or is threatened to be made a party, to a threatened, pending or completed action, suit or proceeding, whether civil, criminal, administrative or investigative (other than an action by or in the right of the corporation), by reason of the fact that the person is or was a director, officer, employee or agent of the corporation, or is or was serving at the request of the corporation as a director, officer, employee or agent of another corporation, partnership, joint venture, trust or other enterprise, against expenses (including attorneys’ fees), judgments, fines and amounts paid in settlement actually and reasonably incurred by the person in connection with such action, suit or proceeding, if the person acted in good faith and in a manner the person reasonably believed to be in, or not opposed to, the best interests of the corporation and, with respect to any criminal action or proceeding, had no reasonable cause to believe the person’s conduct was unlawful.

Section 145(b) of the DGCL provides in relevant part that a corporation may indemnify any person who was or is a party or is threatened to be made a party to any threatened, pending or completed action or suit by or in the right of the corporation to procure a judgment in its favor by reason of the fact that the person is or was a director, officer, employee or agent of the corporation, or is or was serving at the request of the corporation as a director, officer, employee or agent of another corporation, partnership, joint venture, trust or other enterprise against expenses (including attorneys’ fees) actually and reasonably incurred by the person in connection with the defense or settlement of such action or suit if the person acted in good faith and in a manner the person reasonably believed to be in or not opposed to the best interests of the corporation and except that no indemnification shall be made in respect of any claim, issue or matter as to which such person shall have been

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adjudged to be liable to the corporation unless and only to the extent that the Court of Chancery of the State of Delaware or the court in which such action or suit was brought shall determine upon application that, despite the adjudication of liability but in view of all the circumstances of the case, such person is fairly and reasonably entitled to indemnity for such expenses which the Court of Chancery or such other court shall deem proper.

The DGCL also provides that indemnification under Sections 145(a) and (b) can only be made upon a determination that indemnification of the present or former director, officer or employee or agent is proper in the circumstances because such person has met the applicable standard of conduct set forth in Sections 145(a) and (b). Such determination shall be made, with respect to a person who is a director or officer at the time of such determination, (1) by a majority vote of directors who are not a party to the action at issue (even though less than a quorum), (2) by a majority vote of a designated committee of these directors (even though less than a quorum), (3) if there are no such directors, or these directors authorize, by the written opinion of independent legal counsel, or (4) by the stockholders.

Section 145(c) of the DGCL provides that to the extent a present or former director or officer of a corporation has been successful on the merits or otherwise in defense of any action, suit or proceeding referred to in Section 145(a) or (b), or in defense of any claim, issue or matter therein, such person shall be indemnified against expenses (including attorney’s fees) actually and reasonably incurred by such person in connection therewith. Section 145(e) of the DGCL provides that expenses (including attorneys’ fees) incurred by an officer or director of the corporation in defending any civil, criminal, administrative or investigative action, suit or proceeding may be paid by the corporation in advance of the final disposition of such action, suit or proceeding upon receipt of an undertaking by or on behalf of such director or officer to repay such amount if it shall ultimately be determined that such person is not entitled to be indemnified by the corporation as authorized in Section 145 of the DGCL.

Such expenses (including attorneys’ fees) incurred by former directors and officers or other employees and agents of the corporation or by persons serving at the request of the corporation as directors, officers, employees or agents of another corporation, partnership, joint venture, trust or other enterprise may be so paid upon such terms and conditions, if any, as the corporation deems appropriate.

Section 145(g) of the DGCL also empowers a corporation to purchase and maintain insurance on behalf of any person who is or was a director, officer, employee or agent of the corporation, or is or was serving at the request of the corporation as a director, officer, employee or agent of another corporation, partnership, joint venture, trust or other enterprise against any liability asserted against such person and incurred by such person in any such capacity, or arising out of such person’s status as such, whether or not the corporation would have the power to indemnify such person against such liability under Section 145 of the DGCL.

Section 102(b)(7) of the DGCL permits a corporation to provide for eliminating or limiting the personal liability of one of its directors for any monetary damages related to a breach of fiduciary duty as a director, as long as the corporation does not eliminate or limit the liability of a director for (a) a breach of the director’s duty of loyalty to the corporation or its stockholders, (b) acts or omissions not in good faith or involving intentional misconduct or a knowing violation of law, (c) a violation of Section 174 of the DGCL (unlawful dividends) or (d) any transaction from which the director derived an improper personal benefit.

Article 10 of the Charter eliminates the personal liability of the Company’s directors to the fullest extent permitted by the DGCL. Such section eliminates the personal liability of a director to the Company or its stockholders for monetary damages for breach of fiduciary duty owed to the Company or its stockholder as a director, except for liability (a) for any breach of the director’s duty of loyalty to the Company or its stockholders, (b) for acts or omissions not in good faith or which involve intentional misconduct or a knowing violation of law, (c) under Section 174 of the DGCL (unlawful dividends) or (d) for any transaction from which the director derived an improper personal benefit.

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Item 16. Exhibits

Item 17. Undertakings

The undersigned registrant hereby undertakes:

Provided, however, that paragraphs (1)(a), (1)(b) and (1)(c) 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 15(d) of the Exchange Act that are incorporated by reference in the registration statement, or is contained in a form of prospectus filed pursuant to Rule 424(b) that is part of the registration statement.

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SIGNATURES

Pursuant to the requirements of the Securities Act of 1933, as amended, the registrant certifies that it has reasonable grounds to believe that it meets all of the requirements for filing on Form S-3 and has duly caused this registration statement to be signed on its behalf by the undersigned, thereunto duly authorized, in the City of San Diego, California, on November 19, 2024.

KNOW ALL PERSONS BY THESE PRESENTS, that each person whose signature appears below constitutes and appoints Brian J. Blaser, Joseph M. Busky and Michelle A. Hodges, and each of them, his or her true and lawful attorneys-in-fact and agents, each with full power of substitution and resubstitution, for him and in his name, place and stead, in any and all capacities, to sign any and all amendments, including post-effective amendments, to this Registration Statement, and any registration statement relating to the offering covered by this Registration Statement and filed pursuant to Rule 462 under the Securities Act of 1933, as amended, and to file the same, with exhibits thereto and other documents in connection therewith, with the Securities and Exchange Commission, 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, as fully to all intents and purposes as he might or could do in person, hereby ratifying and confirming all that each of said attorneys-in-fact and agents or their substitute or substitutes may lawfully so or cause to be done by virtue hereof.

Pursuant to the requirements of the Securities Act of 1933, as amended, the following persons have signed this Registration Statement in the capacities and on the date indicated.

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Exhibit 5.1

November 19, 2024

QuidelOrtho Corporation

9975 Summers Ridge Road

San Diego, California 92121

Ladies and Gentlemen:

We have examined the Registration Statement on Form S-3, as amended (the “Registration Statement”) of QuidelOrtho Corporation, a Delaware corporation (the “Company”), filed with the Securities and Exchange Commission (the “Commission”) pursuant to the Securities Act of 1933, as amended (the “Securities Act”), in connection with the registration by the Company of up to 8,260,183 shares of the Company’s common stock, par value $0.001 per share (the “Shares”). The Shares are being offered from time to time by certain stockholders of the Company as described in the Registration Statement.

In arriving at the opinions expressed below, we have examined originals, or copies certified or otherwise identified to our satisfaction as being true and complete copies of the originals, of such documents, corporate records, certificates of officers of the Company and of public officials and other instruments as we have deemed necessary or advisable to enable us to render the opinions set forth below. In our examination, we have assumed, without independent investigation, the genuineness of all signatures, the legal capacity and competency of all natural persons, the authenticity of all documents submitted to us as originals and the conformity to original documents of all documents submitted to us as copies.

Based upon the foregoing, and subject to the assumptions, exceptions, qualifications and limitations set forth herein, we are of the opinion that the Shares are validly issued, fully paid and non-assessable.

We render no opinion herein as to matters involving the laws of any jurisdiction other than the Delaware General Corporation Law. This opinion is limited to the effect of the current state of the laws of the State of Delaware and the facts as they currently exist. We assume no obligation to revise or supplement this opinion in the event of future changes in such laws or the interpretations thereof or such facts.

Gibson, Dunn & Crutcher LLP

200 Park Avenue | New York, NY 10166-0193 | T: 212.351.4000 | F: 212.351.4035 | gibsondunn.com

November 19, 2024

QuidelOrtho Corporation

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We consent to the filing of this opinion as an exhibit to the Registration Statement, and we further consent to the use of our name under the caption “Legal Matters” in the Registration Statement and the prospectus that forms a part thereof. In giving these consents, we do not thereby admit that we are within the category of persons whose consent is required under Section 7 of the Securities Act or the Rules and Regulations of the Commission.

Very truly yours,

/s/ Gibson, Dunn & Crutcher LLP

Exhibit 23.1

Consent of Independent Registered Public Accounting Firm

We consent to the reference to our firm under the caption “Experts” in the Registration Statement (Form S-3) and related Prospectus of QuidelOrtho Corporation for the registration of 8,260,183 shares of its common stock and to the incorporation by reference therein of our reports dated February 29, 2024, with respect to the consolidated financial statements of QuidelOrtho Corporation, and the effectiveness of internal control over financial reporting of QuidelOrtho Corporation, included in its Annual Report (Form 10-K) for the year ended December 31, 2023, as amended, and filed with the Securities and Exchange Commission.

/s/ Ernst & Young LLP

San Diego, California

November 19, 2024