Filed pursuant to Rule 424(b)(5)
Registration No. 333-275988

PROSPECTUS SUPPLEMENT

(To Prospectus dated December 19, 2023)

Up to $100,000,000

Common Stock

We entered into a sales agreement dated March 15, 2024 (the “Sales Agreement”) with Needham & Company, LLC and B. Riley Securities, Inc. (each, a “Sales Agent” and together, the “Sales Agents”), relating to the issuance and sale of shares of our common stock, $0.0001 par value per share, offered by this prospectus supplement and the accompanying prospectus. In accordance with the terms of the Sales Agreement, under this prospectus supplement, we may offer and sell shares of our common stock having an aggregate offering price of up to $100,000,000 from time to time through or to the Agents, each acting as our sales agent.

Our common stock is quoted on The Nasdaq Capital Market (“Nasdaq”) under the symbol “RGTI.” On March 14, 2024, the last reported sales price of our common stock on Nasdaq was $1.98 per share.

Sales of our common stock, if any, under this prospectus supplement and the accompanying prospectus may be made by any method permitted that is deemed to be an “at the market offering” as defined in Rule 415(a)(4) promulgated under the Securities Act of 1933, as amended (the “Securities Act”). Neither of the Sales Agents is required to sell any specific number or dollar amount of shares of common stock, but each will act as a sales agent using commercially reasonable efforts consistent with its normal trading and sales practices, on mutually agreed terms between the Sales Agent and us. There is no arrangement for funds to be received in any escrow, trust or similar arrangement.

The compensation to the Sales Agents for sales of common stock sold pursuant to the Sales Agreement will be an amount equal to up to 3.0% of the gross proceeds of any shares of common stock sold under the Sales Agreement. In connection with the sale of the common stock on our behalf, each Sales Agent will be deemed to be an “underwriter” within the meaning of the Securities Act and the compensation of the Sales Agents will be deemed to be underwriting commissions or discounts. We have also agreed in the Sales Agreement to provide indemnification and contribution to each Sales Agent with respect to certain liabilities, including liabilities under the Securities Act or the Securities Exchange Act of 1934, as amended (the “Exchange Act”). See “Plan of Distribution” beginning on page S-11 regarding the compensation to be paid to the Sales Agents.

We are an “emerging growth company” and a “smaller reporting company” as defined under U.S. federal securities laws and, as such, have elected to comply with reduced public company reporting requirements.

Investing in our common stock involves a high degree of risk. See “Risk Factors” on page S-4 of this prospectus supplement, page 4 of the accompanying prospectus and the documents incorporated by reference herein and therein.

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

Needham & Company B. Riley Securities

The date of this prospectus supplement is March 15, 2024

TABLE OF CONTENTS

PROSPECTUS SUPPLEMENT

	Page
ABOUT THIS PROSPECTUS SUPPLEMENT		S-ii
PROSPECTUS SUPPLEMENT SUMMARY		S-1
THE OFFERING		S-3
RISK FACTORS		S-4
CAUTIONARY NOTE REGARDING FORWARD-LOOKING STATEMENTS		S-6
USE OF PROCEEDS		S-8
DILUTION		S-9
PLAN OF DISTRIBUTION		S-11
LEGAL MATTERS		S-12
EXPERTS		S-12
WHERE YOU CAN FIND ADDITIONAL INFORMATION		S-13
INCORPORATION OF CERTAIN INFORMATION BY REFERENCE		S-13

PROSPECTUS

	Page
ABOUT THIS PROSPECTUS		ii
PROSPECTUS SUMMARY		1
RISK FACTORS		6
CAUTIONARY NOTE REGARDING FORWARD-LOOKING STATEMENTS		7
USE OF PROCEEDS		9
DESCRIPTION OF CAPITAL STOCK		10
DESCRIPTION OF DEBT SECURITIES		16
DESCRIPTION OF WARRANTS		23
LEGAL OWNERSHIP OF SECURITIES		26
PLAN OF DISTRIBUTION		30
LEGAL MATTERS		32
EXPERTS		32
WHERE YOU CAN FIND ADDITIONAL INFORMATION		32
INCORPORATION OF CERTAIN INFORMATION BY REFERENCE		33

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ABOUT THIS PROSPECTUS SUPPLEMENT

This prospectus supplement and the accompanying prospectus dated December 19, 2023 are part of a registration statement on Form S-3 that we filed with the Securities and Exchange Commission (the “SEC”) using a “shelf” registration process. Under this shelf registration process, we may from time to time sell any combination of the securities described in the accompanying prospectus in one or more offerings. Under this prospectus supplement, we may from time to time sell shares of our common stock having an aggregate offering price of up to $100,000,000, at prices and on terms to be determined by market conditions at the time of the offering.

This document is in two parts. The first part is this prospectus supplement, which describes the specific terms of this common stock offering and also adds to and updates information contained in the accompanying prospectus and the documents incorporated by reference herein. The second part, the accompanying prospectus, provides more general information. Generally, when we refer to this prospectus, we are referring to both parts of this document combined. To the extent there is a conflict between the information contained in this prospectus supplement and the information contained in the accompanying prospectus or any document incorporated by reference therein filed prior to the date of this prospectus supplement, you should rely on the information in this prospectus supplement; provided that if any statement in one of these documents is inconsistent with a statement in another document having a later date—for example, a document incorporated by reference in the accompanying prospectus—the statement in the document having the later date modifies or supersedes the earlier statement.

We have not, and each of the Sales Agents has not, authorized anyone to provide you with any information other than that contained or incorporated by reference in this prospectus supplement, the accompanying prospectus or in any free writing prospectus that we have authorized for use in connection with this offering. Neither we nor the Sales Agents take any responsibility for, and can provide no assurance as to the reliability of, any other information others may give you. The information contained in this prospectus supplement, the accompanying prospectus, any free writing prospectus that we have authorized for use in connection with this offering, including the documents incorporated by reference herein or therein, is accurate only as of the respective dates thereof, regardless of the time of delivery of this prospectus supplement and the accompanying prospectus or of any sale of our common stock. Our business, financial conditions, liquidity, results of operations and prospects may have changed since those dates. You should read this prospectus supplement, the accompanying prospectus, any free writing prospectus that we have authorized for use in connection with this offering, including the documents incorporated by reference herein or therein, in their entirety before making an investment decision. You should also read and consider the information in the documents to which we have referred you in the sections titled “Where You Can Find Additional Information” and “Incorporation of Certain Information by Reference” in this prospectus supplement and the accompanying prospectus.

We further note that the representations, warranties and covenants made by us in any agreement that is filed as an exhibit to any document that is incorporated by reference herein were made solely for the benefit of the parties to such agreement, including, in some cases, for the purpose of allocating risk among the parties to such agreements, and should not be deemed to be a representation, warranty or covenant to you. Moreover, such representations, warranties or covenants were accurate only as of the date when made. Accordingly, such representations, warranties and covenants should not be relied on as accurately representing the current state of our affairs.

We and the Sales Agents are offering to sell, and seeking offers to buy, shares of our common stock only in jurisdictions where offers and sales are permitted. The distribution of this prospectus supplement and the accompanying prospectus and the offering of the common stock in certain jurisdictions may be restricted by law. Persons outside the United States who come into possession of this prospectus supplement and the accompanying prospectus must inform themselves about, and observe any restrictions relating to, the offering of the common stock and the distribution of this prospectus supplement and the accompanying prospectus outside the United States. This prospectus supplement and the accompanying prospectus do not constitute, and may not be used in connection with, an offer to sell, or a solicitation of an offer to buy, any securities offered by this prospectus supplement and the accompanying prospectus by any person in any jurisdiction in which it is unlawful for such person to make such an offer or solicitation.

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Except as otherwise indicated herein or as the context otherwise requires, references in this prospectus supplement to the “Company,” “Rigetti,” “Rigetti Computing,” “we,” “us,” “our” and similar terms refer to Rigetti Computing, Inc. and its consolidated subsidiaries.

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PROSPECTUS SUPPLEMENT SUMMARY

This summary highlights information contained elsewhere in or incorporated by reference into this prospectus supplement. It does not contain all of the information you should consider before making an investment decision. Before you decide to invest in our common stock, you should carefully read and consider the more detailed information included or incorporated by reference in this prospectus supplement, the accompanying prospectus and any free writing prospectus that we have authorized for use in connection with this offering, including the risk factors included or incorporated by reference herein and therein. You also should carefully read the other information incorporated by reference into this prospectus supplement and the accompanying prospectus, including our financial statements, other information and the exhibits to the registration statement of which this prospectus supplement and the accompanying prospectus are a part.

Company Overview

We build and operate quantum computers. We believe quantum computing represents one of the most transformative emerging capabilities in the world today. By leveraging quantum mechanics, our quantum computers process information in fundamentally new, more powerful ways compared to classical computing. When scaled, we believe these systems are poised to solve problems of staggering computational complexity at unprecedented speed.

We are a vertically integrated company. We own and operate Fab-1, a unique wafer fabrication facility dedicated to prototyping and producing our quantum processors. Through Fab-1, we own the means of production of our breakthrough multi-chip quantum processor technology. We leverage our chips through a full-stack product development approach, from quantum chip design and manufacturing through cloud delivery. We believe this full-stack development approach offers both the fastest and lowest risk path to building commercially valuable quantum computers.

We have been deploying our quantum computers to end users over the cloud since 2017. We offer our full-stack quantum computing platform as a cloud service to a wide range of end-users, directly through our Rigetti Quantum Cloud Services (“QCS”) platform, and also through cloud service providers.

We began selling quantum computers to end users in 2023. In the third quarter of 2023, we expanded our quantum processing unit (“QPU”) customer base with the delivery of a 9-qubit QPU to another premier national laboratory. This follows our first QPU sale in the second quarter of 2023 to Fermilab in which we delivered a 9-qubit QPU as part of our partnership with the Superconducting Quantum Materials and Systems Center. We also launched the Novera^™ QPU in December 2023, our first commercially available QPU, which includes a 9-qubit chip that features tunable couplers for fast 2-qubit operations and a 5-qubit chip for testing single-qubit operations. The Novera QPU is based on our fourth generation Ankaa^™-class architecture. In the fourth quarter of 2023, we made our 84-qubit Ankaa-2 quantum system available publicly via our QCS platform. The Ankaa-2 system is our highest qubit count QPU available to the public and is based on our fourth-generation chip architecture that features tunable couplers and a square lattice, enabling high fidelity 2-qubit operations compared to our previous systems. The Ankaa-2 system has achieved a 98% median 2-qubit fidelity based on our testing, representing a 2.5x improvement in error performance compared to our previous QPUs, and a 2-qubit gate time of 68 nanoseconds — the shortest gate time demonstrated by a Rigetti QPU.We have developed strong customer relationships and collaborative partnerships to accelerate the development of key technologies for high-value use cases to potentially unlock strategic market opportunities.

Our partners and customers include commercial enterprises such as Amazon Web Services, The Nasdaq Stock Market, Standard Chartered Bank and HSBC, along with U.S. government organizations such as Defense Advance Research Projects Agency, Department of Energy, and Air Force Research Laboratory and international government entities. Recently, in February 2024, Rigetti UK Limited, a wholly owned subsidiary of our Company, announced that it was awarded a Small Business Research Initiative grant funded by Innovate UK to develop and deliver a 24-qubit quantum computer to the National Quantum Computing Centre.

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We are enabled by a deep technical team that includes global experts in quantum chip design and manufacturing, quantum computing systems architecture, quantum software, and quantum algorithms and applications.

Powered by the production of our scalable multi-chip quantum processors in Fab-1 and our full-stack product development approach, we are working to develop quantum computing systems that demonstrate clear performance advantages over classical computing alternatives for multiple high-impact application areas.

Corporate Information

We were incorporated under the name “Supernova Partners Acquisition Company II, Ltd.” (“Supernova”) on December 22, 2020 in the Cayman Islands for the purpose of effecting a merger, amalgamation, share exchange, asset acquisition, share purchase, reorganization, or similar business combination with one or more businesses. On March 2, 2022, we consummated the transactions contemplated by that certain Agreement and Plan of Merger dated as of October 6, 2021, as amended on December 23, 2021 and January 10, 2022 (the “Merger Agreement”), by and among Supernova, Supernova Merger Sub, Inc., a Delaware corporation and a direct wholly owned subsidiary of Supernova, Supernova Romeo Merger Sub, LLC, a Delaware limited liability company and a direct wholly owned subsidiary of Supernova, and Rigetti Holdings, Inc., a Delaware corporation. As contemplated by the Merger Agreement, on March 1, 2022, Supernova was domesticated as a Delaware corporation and changed its name to “Rigetti Computing, Inc.”

Our principal executive offices are located at 775 Heinz Avenue, Berkeley, CA 94710 and our telephone number is (510) 210-5550. Our corporate website address is www.rigetti.com. Information contained on or accessible through our website is not a part of this prospectus supplement and the accompanying prospectus, and the inclusion of our website address herein is an inactive textual reference only.

“Rigetti” and our other registered and common law trade names, trademarks and service marks are property of Rigetti Computing, Inc. This prospectus supplement and the accompanying prospectus contain additional trade names, trademarks and service marks of others, which are the property of their respective owners. Solely for convenience, trademarks and trade names referred to herein may appear without the ^® or ^™ symbols.

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THE OFFERING

Common stock offered by us Shares of our common stock having an aggregate offering price of up to $100,000,000.

Common stock to be outstanding
immediately after this offering Up to 208,686,072 shares (as more fully described in the notes following this table), assuming sales of 50,505,050 shares of our common stock in this offering at an assumed offering price of $1.98 per share, which was the last reported sale price of our shares of common stock on Nasdaq on March 8, 2024. The actual number of shares issued will vary depending on the sales price under this offering.

Manner of Offering “At the market offering” that may be made from time to time through or to the Sales Agents. See “Plan of Distribution.”

Use of Proceeds We currently intend to use the net proceeds of this offering primarily for working capital, capital expenditures and general corporate purposes. See “Use of Proceeds” on page S-8 of this prospectus supplement.

Risk Factors Investing in our common stock involves significant risks. See the disclosure under the heading “Risk Factors” on page S-4 in this prospectus supplement and under similar headings in other documents incorporated by reference into this prospectus supplement.

The Nasdaq Capital Market symbol Our common stock is currently traded on Nasdaq under the symbol “RGTI.”

The number of shares of common stock to be outstanding is based on 158,181,022 shares of common stock outstanding as of March 8, 2024, and excludes:

• 9,991,503 shares of common stock issuable upon the settlement of restricted stock units granted under the Rigetti Computing, Inc. 2022 Equity Incentive Plan (the “2022 Plan”) and Rigetti & Co, Inc. 2013 Equity Incentive Plan (the “2013 Plan”) as of March 8, 2024;

• 6,833,301 shares of common stock issuable upon the exercise of options outstanding as of March 8, 2024, with a weighted average exercise price of $0.83 per share, granted under the 2022 Plan, 2013 Plan and QxBranch, Inc. 2018 Equity Compensation Plan;

• 14,368,854 shares of common stock reserved for future issuance under the 2022 Plan as of March 8, 2024;

• 4,681,989 shares of common stock reserved for future issuance under the Rigetti Computing, Inc. 2022 Employee Stock Purchase Plan as of March 8, 2024; and

• 13,074,972 shares of common stock issuable upon the exercise of warrants outstanding as of March 8, 2024, with an exercise price of $11.50 per share, and 3,688,333 shares of common stock issuable upon the exercise of Rigetti assumed warrants as of March 8, 2024, with a weighted average exercise price of $1.06 per share.

Except as otherwise indicated, all information in this prospectus supplement and the accompanying prospectus assumes no exercise of the outstanding options or warrants referred to above, no vesting and settlement of the outstanding restricted stock units referred to above, and no sales pursuant to the Sales Agreement other than this offering.

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RISK FACTORS

Investment in the shares of common stock offered pursuant to this prospectus supplement and the accompanying prospectus involves risks. You should carefully consider the risk factors described below, as well as the risk factors described under the caption “Risk Factors” in our most recent Annual Report on Form 10-K and Quarterly Report on Form 10-Q, and the other information contained or incorporated by reference in this prospectus supplement and the accompanying prospectus, including our financial statements and the related notes, as may be updated by our subsequent filings under the Exchange Act, and in any free writing prospectus that we have authorized for use in connection with this offering before acquiring shares of our common stock. The occurrence of any of these risks could have a material and adverse impact on our business, results of operations, financial condition and growth prospects, which may cause the trading price of our common stock to decline and you could lose all or part of your investment.

Risks Relating to this Offering

We have broad discretion in the use of the net proceeds from this offering and may not use them effectively.

Our management will have broad discretion in the application of the net proceeds from this offering, including for any of the purposes described in the section entitled “Use of Proceeds,” and you will not have the opportunity as part of your investment decision to assess whether the net proceeds are being used appropriately. Because of the number and variability of factors that will determine our use of the net proceeds from this offering, their ultimate use may vary substantially from their currently intended use. Our management might not apply our net proceeds in ways that ultimately increase the value of your investment. Our failure to apply these funds effectively could have a material adverse effect on our business and cause the price of our common stock to decline.

If you purchase shares of our common stock sold in this offering, you may experience immediate and substantial dilution in the net tangible book value of your shares.

The price per share of our common stock being offered may be higher than the net tangible book value per share of our outstanding common stock prior to this offering. Assuming that an aggregate of 50,505,050 shares of our common stock are sold at an assumed offering price of $1.98 per share, the last reported sale price of our common stock on Nasdaq on March 8, 2024, for aggregate gross proceeds of approximately $100,000,000, and after deducting commissions and estimated offering expenses payable by us, new investors in this offering will incur immediate dilution of $0.96 per share. For a more detailed discussion of the foregoing, see the section entitled “Dilution” below. To the extent that any options or warrants are exercised, any restricted stock units vest and are settled, any new equity awards are issued under our equity incentive plans, or we otherwise issue additional shares of common stock in the future (including shares issued in connection with strategic and other transactions), there will be further dilution to new investors.

You may experience dilution if we issue additional equity securities in future fundraising transactions.

To raise additional capital, we may in the future offer additional shares of our common stock or other securities convertible into or exchangeable for our common stock at prices that may not be the same as the price per share in this offering. We may sell shares or other securities in any other offering at a price per share that is less than the price per share paid by investors in this offering, and investors purchasing shares or other securities in the future could have rights superior to existing stockholders. The price per share at which we sell additional shares of our common stock, or securities convertible or exchangeable into common stock, in future transactions may be higher or lower than the price per share paid by investors in this offering.

Future resales of our common stock could cause the market price of our common stock to drop significantly, even if our business is doing well.

Sales of a substantial number of shares of our common stock in the public market could occur at any time. These sales, or the perception in the market that the holders of a large number of shares intend to sell shares, could reduce the market price of our common stock or cause it to be highly volatile and impair our ability to raise capital through the sale of additional equity securities. A substantial number of shares of common stock are being offered by this

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prospectus supplement, and we cannot predict if and when shares sold in this offering, if any, will be resold in the public markets. We cannot predict the number of these shares that might be resold nor the effect that future sales of our shares of common stock would have on the market price of shares of our common stock.

The actual number of shares we will issue under the Sales Agreement, at any one time or in total, is uncertain.

Subject to certain limitations in the Sales Agreement and compliance with applicable law, we have the discretion to deliver a placement notice to a Sales Agent at any time throughout the term of the Sales Agreement. The number of shares that are sold by a Sales Agent after delivering a placement notice will fluctuate based on the market price of the common stock during the sales period and limits we set with such Sales Agent. Because the price per share of each share sold will fluctuate based on the market price of our common stock during the sales period, it is not possible at this stage to predict the number of shares that will be ultimately issued or the aggregate proceeds to be raised in connection with sales under the Sales Agreement.

The common stock offered hereby will be sold in “at the market offerings”, and investors who buy shares at different times will likely pay different prices.

Investors who purchase shares in this offering at different times will likely pay different prices, and so may experience different outcomes in their investment results. We will have discretion, subject to market demand, to vary the timing, prices, and numbers of shares sold, and there is no minimum or maximum sales price. Investors may experience a decline in the value of their shares as a result of share sales made at prices lower than the prices they paid.

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CAUTIONARY NOTE REGARDING FORWARD-LOOKING STATEMENTS

Certain matters discussed in this prospectus supplement, the accompanying prospectus, the documents incorporated by reference and any free writing prospectus that we have authorized for use in connection with this offering may constitute forward-looking statements within the meaning of Section 27A of the Securities Act and Section 21E of the Exchange Act, and involve known and unknown risks, uncertainties and other factors that may cause our actual results, performance or achievements to be materially different from the future results, performance or achievements expressed or implied by such forward-looking statements. The words “anticipate,” “believe,” “estimate,” “may,” “might,” “expect,” “intend,” “plan,” “possible,” “potential,” “predict,” “project,” “should,” “would,” “could” and similar expressions are generally intended to identify forward-looking statements. Our actual results may differ materially from the results anticipated in these forward-looking statements due to a variety of factors, including, without limitation, those discussed in the section entitled “Risk Factors,” and elsewhere in this prospectus supplement, the accompanying prospectus and the documents incorporated by reference herein and therein, where such forward-looking statements appear. All written or oral forward-looking statements attributable to us are expressly qualified in their entirety by these cautionary statements. Such forward-looking statements include, but are not limited to, statements about:

• the sufficiency of our cash resources, our expectations with respect to when we will need to obtain additional capital, and our ability to raise additional capital when needed and on attractive terms;

• our ability to achieve milestones, and/or technological advancements, including with respect to executing on our technology roadmap and developing practical applications;

• the potential of quantum computing and estimated market size and market growth including with respect to our long-term business strategy for quantum computing as a service;

• the success of our partnerships and collaborations;

• our ability to accelerate our development of multiple generations of quantum processors;

• customer concentration and the risk that a significant portion of our revenue currently depends on contracts with the public sector;

• the outcome of any legal proceedings that may be instituted against us or others;

• our ability to execute on our business strategy, including monetization of our products;

• our financial performance, growth rate and market opportunity;

• our ability to maintain compliance with standards relating to the listing of our common stock and public warrants on Nasdaq and the potential liquidity and trading of such securities;

• the ability to recognize the anticipated benefits of the Business Combination, which may be affected by, among other things, competition, our ability to grow and manage growth profitably, maintain relationships with customers and suppliers and retain our management and key employees;

• costs related to operating as a public company;

• our ability to remediate the material weaknesses in, and establish and maintain, effective internal controls over financial reporting;

• changes in applicable laws or regulations;

• the possibility that we may be adversely affected by other economic, business, or competitive factors;

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• the evolution of the markets in which we compete;

• our ability to implement our strategic initiatives, expansion plans and continue to innovate our existing services;

• unfavorable conditions in our industry, the global economy or global supply chain (including any supply chain impacts from the ongoing military conflicts involving Russia and Ukraine and sanctions related thereto and the state of war between Israel and Hamas and the potential larger regional conflict), including inflation and financial and credit market fluctuations;

• changes in applicable laws or regulations;

• our success in retaining or recruiting, or changes required in, our officers, key employees or directors;

• our estimates regarding expenses, profitability, future revenue, capital requirements and needs for additional financing;

• our ability or decisions to expand or maintain our existing customer base;

• macroeconomic conditions, including worsening global economic conditions, disruptions to and volatility and uncertainty in the credit and financial markets, increases in inflation and interest rates, and recent and potential future disruptions in access to bank deposits or lending commitments due to bank failures, on the foregoing;

• our anticipated use of the net proceeds of this offering; and

• other factors detailed under the section entitled “Risk Factors.”

The forward-looking statements contained in this prospectus supplement, the accompanying prospectus, the documents incorporated by reference and any free writing prospectus that we have authorized for use in connection with this offering reflect our views and assumptions only as of the date of this prospectus supplement or such other document, as applicable. Except as required by law, we assume no responsibility for updating any forward-looking statements. You should read this prospectus supplement and accompanying prospectus together with the documents we have filed with the SEC that are incorporated by reference and any free writing prospectus that we may authorize for use in connection with this offering completely and with the understanding that our actual future results may be materially different from what we expect. We qualify all of the forward-looking statements in the foregoing documents by these cautionary statements.

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USE OF PROCEEDS

We may issue and sell shares of our common stock having aggregate sales proceeds of up to $100,000,000 from time to time. Because there is no minimum offering amount required as a condition to close this offering, the actual total public offering amount, commissions and proceeds to us, if any, are not determinable at this time. There can be no assurance that we will sell any shares under or fully utilize the Sales Agreement as a source of financing.

We currently intend to use any net proceeds from the sale of common stock under this prospectus supplement primarily for working capital, capital expenditures and other general corporate purposes.

The amounts and timing of our actual expenditures will depend on numerous factors, including the factors described under “Risk Factors” in this prospectus supplement, the accompanying prospectus and the documents incorporated by reference herein and therein, as well as the amount of cash used in our operations. We may find it necessary or advisable to use the net proceeds for other purposes, and we will have broad discretion in the application of the net proceeds. Pending the uses described above, we plan to invest the net proceeds from this offering in high-quality, short-term, interest-bearing obligations, investment-grade instruments or certificates of deposit.

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DILUTION

If you invest in our common stock, your interest will be diluted to the extent of the difference between the price per share you pay in this offering and the net tangible book value per share of our common stock immediately after this offering. Our net tangible book value of our common stock as of December 31, 2023 was $102.0 million, or $0.69 per share of common stock based upon 147,066,336 shares outstanding. Net tangible book value per share is equal to our total tangible assets, less our total liabilities, divided by the total number of shares outstanding as of December 31, 2023.

After giving effect to the sale of our common stock in the aggregate amount of $100.0 million at an assumed offering price of $1.98 per share, the last reported sale price of our common stock on Nasdaq on March 8, 2024, and after deducting commissions and estimated offering expenses payable by us, our as adjusted net tangible book value as of December 31, 2023 would have been $201.6 million, or $1.02 per share of common stock. This represents an immediate increase in net tangible book value of $0.33 per share to our existing stockholders and an immediate dilution in net tangible book value of $0.96 per share to new investors in this offering.

The following table illustrates this calculation on a per share basis. The as-adjusted information is illustrative only and will adjust based on the actual price to the public, the actual number of shares sold and other terms of the offering determined at the time shares of our common stock are sold pursuant to this prospectus supplement. The as-adjusted information assumes that all of our common stock in the aggregate amount of $100.0 million is sold at the assumed offering price of $1.98 per share, the last reported sale price of our common stock on Nasdaq on March 8, 2024. The shares sold in this offering, if any, will be sold from time to time at various prices.

Assumed public offering price per share			$	1.98
Historical net tangible book value per share as of December 31, 2023	$	0.69
Increase in net tangible book value per share attributable to the offering	$	0.33
As adjusted net tangible book value per share, after this offering			$	1.02
Dilution per share to investors purchasing shares in this offering			$	0.96

An increase of $1.00 per share in the price at which the shares are sold from the assumed offering price of $1.98 per share shown in the table above, assuming that all of our common stock in the aggregate amount of $100.0 million during the term of the Sales Agreement with the Sales Agents is sold at that price, would increase our as adjusted net tangible book value per share to $1.28 and would increase the dilution in net tangible book value per share to new investors in this offering to $1.70, after deducting commissions and estimated offering expenses payable by us. A decrease of $1.00 per share in the price at which the shares are sold from the assumed offering price of $1.98 per share shown in the table above, assuming all of our common stock in the aggregate amount of $100.0 million during the term of the Sales Agreement with the Sales Agents is sold at that price, would decrease our as adjusted net tangible book value per share to $0.76 and would decrease the dilution in net tangible book value per share to new investors in this offering to $0.22, after deducting commissions and estimated offering expenses payable by us.

The number of shares of common stock to be outstanding is based on 147,066,336 shares of common stock outstanding as of December 31, 2023, and excludes:

• 11,521,329 shares of common stock issuable upon the settlement of restricted stock units granted under the 2022 Plan and the 2013 Plan as of December 31, 2023;

• 7,049,290 shares of common stock issuable upon the exercise of options outstanding as of December 31, 2023, with a weighted average exercise price of $0.82 per share, granted under the 2022 Plan, 2013 Plan and QxBranch, Inc. 2018 Equity Compensation Plan;

• 4,558,706 shares of common stock reserved for future issuance under the 2022 Plan as of December 31, 2023;

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• 4,681,989 shares of common stock reserved for future issuance under the Rigetti Computing, Inc. 2022 Employee Stock Purchase Plan as of December 31, 2023; and

• 13,047,972 shares of common stock issuable upon the exercise of warrants outstanding as of December 31, 2023, with an exercise price of $11.50 per share, and 3,688,333 shares of common stock issuable upon the exercise of Rigetti assumed warrants as of December 31, 2023, with a weighted average exercise price of $1.06 per share.

Except as otherwise indicated, all information in this prospectus supplement and the accompanying prospectus assumes no exercise of the outstanding options or warrants referred to above, no vesting and settlement of the outstanding restricted stock units referred to above, and no sales pursuant to the Sales Agreement other than this offering.

In addition, we may choose to raise additional capital due to market conditions or strategic considerations even if we believe we have sufficient funds for our current or future operating plans. If we raise additional capital through the sale of equity or convertible debt securities, you will experience further dilution.

S-10

PLAN OF DISTRIBUTION

We have entered into the Sales Agreement with the Sales Agents relating to the sale of shares of our common stock offered by this prospectus supplement. Under this prospectus supplement, in accordance with the terms of the Sales Agreement, we may sell shares of our common stock for an aggregate offering price of up to $100,000,000 from time to time through or to the Sales Agents, acting as sales agents, subject to certain limitations, including the number or dollar amount of shares registered under the registration statement to which the offering relates. The sales, if any, of shares made under the Sales Agreement will be made by any method that is deemed an “at the market offering” as defined in Rule 415 promulgated under the Securities Act. We may instruct the Sales Agents not to sell common stock if the sales cannot be effected at or above the price designated by us from time to time. We or the designated Sales Agent may suspend the offering of common stock upon notice and subject to other conditions.

Each time we wish to issue and sell common stock under the Sales Agreement, we will notify the designated Sales Agent of the number or dollar value of shares to be issued, the dates on which such sales are anticipated to be made, any minimum price below which sales may not be made and other sales parameters as we deem appropriate. Once we have so instructed the designated Sales Agent, unless it declines to accept the terms of the notice, the Sales Agent has agreed to use its commercially reasonable efforts consistent with its normal trading and sales practices to sell such shares up to the amount specified on such terms. The obligations of each Sales Agent under the Sales Agreement to sell our common stock is subject to a number of conditions that we must meet.

We will pay the Sales Agents an aggregate commission equal to up to 3.0% of the gross proceeds from the sale of common stock offered hereby. In addition, we have agreed to reimburse certain expenses of the Sales Agents in an amount not to exceed $75,000 in connection with the establishment of this “at the market offering.” In accordance with Financial Industry Regulatory Authority, Inc. Rule 5110, these fees and reimbursed expenses are deemed sales compensation in connection with this offering. We estimate that the total expenses for the offering, excluding compensation payable to any designated Sales Agent under the terms of the Sales Agreement, will be approximately $400,000.

Settlement for sales of common stock will generally occur on the second trading day following the date on which any sales are made, or on some other date that is agreed upon by us and the designated Sales Agent in connection with a particular transaction, in return for payment of the net proceeds to us. There is no arrangement for funds to be received in an escrow, trust or similar arrangement.

In connection with the sale of shares of our common stock on our behalf, each Sales Agent will be deemed to be an “underwriter” within the meaning of the Securities Act and the compensation of such Sales Agent will be deemed to be underwriting commissions or discounts. We have agreed to provide indemnification and contribution to the Sales Agents against certain civil liabilities, including liabilities under the Securities Act. We have also agreed to reimburse the Sales Agents for certain other specified expenses.

The offering of our common stock pursuant to this prospectus supplement will terminate upon the earlier of (i) the sale of all of our common stock provided for in this prospectus supplement or (ii) termination of the Sales Agreement as provided therein.

Our common stock is listed on The Nasdaq Capital Market under the symbol “RGTI.” The transfer agent for our common stock is American Stock Transfer & Trust Company.

Each Sales Agent and its respective affiliates may in the future provide various investment banking and other financial services for us and our affiliates, for which services they may in the future receive customary fees. An affiliate of B. Riley Securities, Inc. was the counterparty to our committed equity financing pursuant to a Common Stock Purchase Agreement, dated as of August 11, 2022, in connection therewith we have registration obligations pursuant to the Registration Rights Agreement, dated as of August 11, 2022. To the extent required by Regulation M, the Sales Agents will not engage in any market making activities involving our common stock while the offering is ongoing under this prospectus supplement.

S-11

LEGAL MATTERS

Cooley LLP, Los Angeles, California, will pass upon the validity of the shares of common stock offered hereby. DLA Piper LLP (US), Austin, Texas, is counsel to the Sales Agents in connection with this offering.

EXPERTS

The consolidated financial statements of Rigetti Computing, Inc. as of December 31, 2023 and 2022, and for each of the years then ended, incorporated by reference in this prospectus supplement and in the registration statement have been so incorporated in reliance on the report of BDO USA, P.C., an independent registered public accounting firm, given on the authority of said firm as experts in auditing and accounting.

S-12

WHERE YOU CAN FIND ADDITIONAL INFORMATION

We file reports, proxy statements and other information with the SEC. The SEC maintains a website that contains reports, proxy and information statements and other information about issuers, such as us, who file electronically with the SEC. The address of that website is www.sec.gov.

Our website address is www.rigetti.com. The information on our website, however, is not, and should not be deemed to be, a part of this prospectus supplement.

This prospectus supplement is part of a registration statement that we filed with the SEC and do not contain all of the information in the registration statement. The full registration statement may be obtained from the SEC or us, as provided below. Statements in this prospectus supplement about these documents are summaries, and each statement is qualified in all respects by reference to the document to which it refers. You should refer to the actual documents for a more complete description of the relevant matters. You may inspect a copy of the registration statement through the SEC’s website, as provided above.

INCORPORATION OF CERTAIN INFORMATION BY REFERENCE

The SEC’s rules allow us to “incorporate by reference” information into this prospectus supplement, which means that we can disclose important information to you by referring you to another document filed separately with the SEC. The information incorporated by reference is considered to be part of this prospectus supplement and the accompanying prospectus. Information in this prospectus supplement and the accompanying prospectus supersedes information incorporated by reference that we filed with the SEC prior to the date of this prospectus supplement and the accompanying prospectus, while information that we file later with the SEC will automatically update and supersede the information in this prospectus supplement and the accompanying prospectus. We incorporate by reference into this prospectus supplement, the accompanying prospectus and the registration statement of which this prospectus supplement and the accompanying prospectus are a part the information or documents listed below that we have filed with the SEC, excluding any portions of any Form 8-K that are not deemed “filed” pursuant to the General Instructions of Form 8-K, unless indicated otherwise:

• our Annual Report on Form 10-K for the year ended December 31, 2023, filed with the SEC on March 14, 2024;

• our Current Reports on Form 8-K filed with the SEC on February 5, 2024 (including Item 2.02), February  15, 2024, February  23, 2024 and March 15, 2024; and

• the description of securities contained in a Registration Statement on Form 8-A filed on March  1, 2022, as updated by Exhibit 4.4 to our Annual Report on Form 10-K for the year ended December 31, 2022, filed with the SEC on March 27, 2023, together with any amendment or report filed with the SEC for the purpose of updating such description.

We also incorporate by reference any future filings (other than current reports furnished under Item 2.02 or Item 7.01 of Form 8-K and exhibits filed on such form that are related to such items unless such Form 8-K expressly provides to the contrary) made with the SEC pursuant to Sections 13(a), 13(c), 14 or 15(d) of the Exchange Act. Information in such future filings updates and supplements the information provided in this prospectus supplement and the accompanying prospectus. Any statements in any such future filings will automatically be deemed to modify and supersede any information in any document we previously filed with the SEC that is incorporated or deemed to be incorporated herein by reference to the extent that statements in the later filed document modify or replace such earlier statements.

You can request a copy of these filings, at no cost, by writing or telephoning us at the following address or telephone number:

Rigetti Computing, Inc.

775 Heinz Avenue

Berkeley, California 94710

Attn: General Counsel

(510) 210-5550

S-13

PROSPECTUS

$250,000,000

RIGETTI COMPUTING, INC.

Common Stock

Preferred Stock

Debt Securities

Warrants

From time to time, we may offer and sell up to an aggregate amount of $250,000,000 of any combination of the securities described in this prospectus, either individually or in combination, at prices and on terms described in one or more supplements to this prospectus. We may also offer common stock, common stock or preferred stock upon conversion of debt securities, common stock upon conversion of preferred stock, or common stock, preferred stock or debt securities upon exercise of warrants.

This prospectus describes some of the general terms that may apply to an offering of our securities. We will provide the specific terms of these offerings and securities in one or more supplements to this prospectus. We may also authorize one or more free writing prospectuses to be provided to you in connection with these offerings. The prospectus supplement and any related free writing prospectus may also add, update or change information contained in this prospectus. You should carefully read this prospectus, the applicable prospectus supplement and any related free writing prospectus, as well as any documents incorporated by reference, before buying any of the securities being offered.

Our common stock and public warrants are listed on the Nasdaq Capital Market under the symbols “RGTI” and “RGTIW,” respectively. On December 8, 2023, the last reported sales price of our common stock was $1.04 per share and the last reported sales price of our public warrants was $0.17 per warrant. The applicable prospectus supplement will contain information, where applicable, as to other listings, if any, on the Nasdaq Capital Market or any securities market or other exchange of the securities covered by the applicable prospectus supplement.

Investing in our securities involves a high degree of risk. You should review carefully the risks and uncertainties described under the section titled “Risk Factors” on page 6 of this prospectus and any similar section contained in the applicable prospectus supplement and in any free writing prospectuses we have authorized for use in connection with a specific offering, and under similar headings in the documents that are incorporated by reference into this prospectus.

This prospectus may not be used to consummate a sale of securities unless accompanied by a prospectus supplement.

The securities may be sold directly by us to investors, through agents designated from time to time or to or through underwriters or dealers, on a continuous or delayed basis. For additional information on the methods of sale, you should refer to the section titled “Plan of Distribution” in this prospectus. If any agents or underwriters are involved in the sale of any shares of our securities with respect to which this prospectus is being delivered, the names of such agents or underwriters and any applicable fees, commissions, discounts and overallotment options will be set forth in a prospectus supplement. The price to the public of such securities and the net proceeds we expect to receive from such sale will also be set forth in a prospectus supplement.

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.

The date of this prospectus is December 19, 2023.

TABLE OF CONTENTS

	Page
ABOUT THIS PROSPECTUS		ii
PROSPECTUS SUMMARY		1
RISK FACTORS		6
CAUTIONARY NOTE REGARDING FORWARD-LOOKING STATEMENTS		7
USE OF PROCEEDS		9
DESCRIPTION OF CAPITAL STOCK		10
DESCRIPTION OF DEBT SECURITIES		16
DESCRIPTION OF WARRANTS		23
LEGAL OWNERSHIP OF SECURITIES		26
PLAN OF DISTRIBUTION		30
LEGAL MATTERS		32
EXPERTS		32
WHERE YOU CAN FIND ADDITIONAL INFORMATION		32
INCORPORATION OF CERTAIN INFORMATION BY REFERENCE		33

i

ABOUT THIS PROSPECTUS

This prospectus is part of a registration statement on Form S-3 that we filed with the Securities and Exchange Commission, or the SEC, using a “shelf” registration process under the Securities Act of 1933, as amended, or the Securities Act. Under this shelf registration statement, we may, from time to time, offer and sell in one or more offerings common stock and preferred stock, various series of debt securities and/or warrants to purchase any of such securities, either individually or in combination with other securities, in one or more offerings, up to a total dollar amount of $250,000,000 of any combination of the securities described in this prospectus. This prospectus provides you with a general description of the securities we may offer.

Each time we sell any type or series of securities under this prospectus, we will provide a prospectus supplement that will contain more specific information about the terms of that offering. We may also authorize one or more free writing prospectuses to be provided to you that may contain material information relating to these offerings. The prospectus supplement and any related free writing prospectus that we may authorize to be provided to you may also add, update or change any of the information contained in this prospectus or in the documents that we have incorporated by reference into this prospectus. This prospectus, together with the applicable prospectus supplement, any related free writing prospectus and the documents incorporated by reference into this prospectus and the applicable prospectus supplement, will include all material information relating to the applicable offering. We urge you to read carefully this prospectus, any applicable prospectus supplement and any related free writing prospectuses we have authorized for use in connection with a specific offering, together with the information incorporated herein, or therein by reference as described under the heading “Incorporation of Certain Information by Reference,” before buying any of the securities being offered.

This prospectus may not be used to consummate a sale of securities unless it is accompanied by a prospectus supplement.

We have not authorized anyone to provide you with any information other than that contained or incorporated by reference in this prospectus and any applicable prospectus supplement, along with the information contained in any free writing prospectuses we have authorized for use in connection with a specific offering. You must not rely upon any information or representation not contained or incorporated by reference in this prospectus, any accompanying prospectus supplement or in any related free writing prospectus that we may authorize to be provided to you. We take no responsibility for, and can provide no assurance as to the reliability of, any other information that others may give you. This prospectus is an offer to sell only the securities offered hereby, but only under circumstances and in jurisdictions where it is lawful to do so. No action is being taken in any jurisdiction outside the United States to permit a public offering of our securities or possession or distribution of this prospectus in that jurisdiction. Persons who come into possession of this prospectus in jurisdictions outside the United States are required to inform themselves about and to observe any restrictions as to this offering and the distribution of this prospectus applicable to that jurisdiction.

The information appearing in this prospectus, any applicable prospectus supplement or any related free writing prospectus is accurate only as of the date on the front of the document and any information we have incorporated by reference is accurate only as of the date of the document incorporated by reference, regardless of the time of delivery of this prospectus, any applicable prospectus supplement or any related free writing prospectus, or the date of any sale of securities. Our business, financial condition, results of operations and prospects may have changed since those dates.

This prospectus contains and incorporates by reference market data and industry statistics and forecasts that are based on independent industry publications and other publicly available information. Although we believe that these sources are reliable, we do not guarantee the accuracy or completeness of this information and we have not independently verified this information. Although we are not aware of any misstatements regarding the market and industry data presented in this prospectus and the documents incorporated herein by reference, these estimates involve risks and uncertainties and are subject to change based on various factors, including those discussed under the section titled “Risk Factors” contained in the applicable prospectus supplement and any related free writing prospectus, and under similar headings in the other documents that are incorporated by reference into this prospectus, the applicable prospectus supplement and any related free writing prospectus. Accordingly, investors should not place undue reliance on this information.

ii

This prospectus contains summaries of certain provisions contained in some of the documents described herein, but reference is made to the actual documents for complete information. All of the summaries are qualified in their entirety by the actual documents. Copies of some of the documents referred to herein have been filed, will be filed or will be incorporated by reference as exhibits to the registration statement of which this prospectus is a part, and you may obtain copies of those documents as described below under the section titled “Where You Can Find Additional Information.”

Unless the context indicates otherwise, references in this prospectus to the “Company,” “Rigetti,” “Rigetti Computing,” “we,” “us,” “our” and similar terms refer to Rigetti Computing, Inc. and its consolidated subsidiaries.

iii

PROSPECTUS SUMMARY

This summary highlights selected information contained elsewhere in this prospectus or incorporated by reference in this prospectus, and does not contain all of the information that you need to consider in making your investment decision. You should carefully read the entire prospectus, the applicable prospectus supplement and any related free writing prospectus, including the risks of investing in our securities discussed under the sections titled “Risk Factors” contained in this prospectus, the applicable prospectus supplement and any related free writing prospectus, and under similar sections in the other documents that are incorporated by reference into this prospectus. You should also carefully read the other information incorporated by reference into this prospectus, including our financial statements, and the exhibits to the registration statement of which this prospectus is a part.

Rigetti Computing, Inc.

Overview

We build quantum computers and the superconducting quantum processors that power them. We believe quantum computing represents one of the most transformative emerging capabilities in the world today. By leveraging quantum mechanics, we believe our quantum computers process information in fundamentally new, more powerful ways than classical computers.

We are a vertically integrated company. We own and operate Fab-1, a unique wafer fabrication facility dedicated to prototyping and producing our quantum processors. Through Fab-1, we own the means of production of our breakthrough multi-chip quantum processor technology. We leverage our chips through a full-stack product development approach, from quantum chip design and manufacturing through cloud delivery.

We have been deploying our quantum computers to end users over the cloud since 2017. We offer our full-stack quantum computing platform as a cloud service to a wide range of end-users, directly through our Rigetti QCS platform, and also through cloud service providers.

We began selling quantum computers to end users in 2023. In the third quarter of 2023 we expanded our QPU customer base with the delivery of a 9-qubit quantum processing unit (QPU) to another premier national laboratory. This follows our first QPU sale in the second quarter of 2023 to Fermilab in which we delivered a 9Q QPU as part of our partnership with the Superconducting Quantum Materials and Systems Center (SQMS).

We have developed strong customer relationships and collaborative partnerships to accelerate the development of key technologies for high-value use cases that unlock strategic early markets. Our partners and customers include commercial enterprises such as Amazon Web Services, Nasdaq and Standard Chartered Bank, along with U.S. government organizations such as the Defense Advanced Research Project Agency (“DARPA”), the Department of Energy (“DOE”), and the National Aeronautics and Space Administration (“NASA”).

We are enabled by a deep technical team that includes global experts in quantum chip design and manufacturing, quantum computing systems architecture, quantum software, and quantum algorithms and applications.

Powered by the production of our scalable multi-chip quantum processors in Fab-1 and our full-stack product development approach, our goal is to deliver quantum computing systems that demonstrate clear performance advantages over classical computing alternatives for multiple high-impact application areas.

Corporate Information

We were incorporated under the name “Supernova Partners Acquisition Company II, Ltd.” (“Supernova”) on December 22, 2020 in the Cayman Islands for the purpose of effecting a merger, amalgamation, share exchange, asset acquisition, share purchase, reorganization, or similar business combination with one or more businesses. On March 2, 2022, we consummated the transactions contemplated by that certain Agreement and Plan of Merger dated as of October 6, 2021, as amended on December 23, 2021 and January 10, 2022 (the “Merger Agreement”), by and among Supernova, Supernova Merger Sub, Inc., a Delaware corporation and a direct wholly owned subsidiary of Supernova,

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Supernova Romeo Merger Sub, LLC, a Delaware limited liability company and a direct wholly owned subsidiary of Supernova, and Rigetti Holdings, Inc., a Delaware corporation. As contemplated by the Merger Agreement, on March 1, 2022, Supernova was domesticated as a Delaware corporation and changed its name to “Rigetti Computing, Inc.”

Our principal executive offices are located at 775 Heinz Avenue, Berkeley, CA 94710 and our telephone number is (510) 210-5550. Our corporate website address is www.rigetti.com. Information contained on or accessible through our website is not a part of this prospectus, and the inclusion of our website address in this prospectus is an inactive textual reference only.

“Rigetti” and our other registered and common law trade names, trademarks and service marks are property of Rigetti Computing, Inc. This prospectus contains additional trade names, trademarks and service marks of others, which are the property of their respective owners. Solely for convenience, trademarks and trade names referred to in this prospectus may appear without the ® or ^™ symbols.

Emerging Growth Company and Smaller Reporting Company Status

We are an “emerging growth company,” as defined in the Jumpstart Our Business Startups Act of 2012 (the “JOBS Act”). As an emerging growth company, we are exempt from certain requirements related to executive compensation, including the requirements to hold a nonbinding advisory vote on executive compensation and to provide information relating to the ratio of total compensation of our Chief Executive Officer to the median of the annual total compensation of all of our employees, each as required by the Investor Protection and Securities Reform Act of 2010, which is part of the Dodd-Frank Act.

Section 102(b)(1) of the JOBS Act exempts emerging growth companies from being required to comply with new or revised financial accounting standards until private companies are required to comply with the new or revised financial accounting standards. The JOBS Act provides that a company can choose not to take advantage of the extended transition period and comply with the requirements that apply to non-emerging growth companies, and any such election to not take advantage of the extended transition period is irrevocable. Supernova previously elected to avail itself of the extended transition period and we will take advantage of the benefits of the extended transition period emerging growth company status permits. During the extended transition period, it may be difficult or impossible to compare our financial results with the financial results of another public company that complies with public company effective dates for accounting standard updates because of the potential differences in accounting standards used.

We will remain an emerging growth company under the JOBS Act until the earliest of (a) December 31, 2026 (the last day of the fiscal year following the fifth anniversary of the consummation of the IPO), (b) the last date of our fiscal year in which we have a total annual gross revenue of at least $1.235 billion, (c) the date on which we are deemed to be a “large accelerated filer” under the rules of the SEC with at least $700.0 million of outstanding securities held by non-affiliates or (d) the date on which we have issued more than $1.0 billion in non-convertible debt securities during the previous three years.

We are also a “smaller reporting company” as defined in the Exchange Act. We may continue to be a smaller reporting company even after we are no longer an emerging growth company. We may take advantage of certain of the scaled disclosures available to smaller reporting companies and will be able to take advantage of these scaled disclosures for so long as the market value of our voting and non-voting common stock held by non-affiliates is less than $250.0 million measured on the last business day of our second fiscal quarter, or our annual revenue is less than $100.0 million during the most recently completed fiscal year and the market value of our voting and non-voting common stock held by non-affiliates is less than $700.0 million measured on the last business day of our second fiscal quarter.

The Securities We May Offer

We may offer shares of our common stock and preferred stock, various series of debt securities and/or warrants to purchase any of such securities, either individually or in combination with other securities, up to a total dollar amount of $250,000,000, from time to time under this prospectus, together with the applicable prospectus supplement

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and any related free writing prospectus, at prices and on terms to be determined by market conditions at the time of any offering. We may also offer common stock, preferred stock and/or debt securities upon the exercise of warrants. This prospectus provides you with a general description of the securities we may offer. Each time we offer a type of security or series of securities under this prospectus, we will provide a prospectus supplement that will describe the specific amounts, prices and other important terms of the securities, including, to the extent applicable:

• designation or classification;

• aggregate principal amount or aggregate offering price;

• maturity date, if applicable;

• original issue discount, if any;

• rates and times of payment of interest or dividends, if any;

• redemption, conversion, exercise, exchange or sinking fund terms, if any;

• ranking;

• restrictive covenants, if any;

• voting or other rights, if any;

• conversion or exchange prices or rates, if any, and, if applicable, any provisions for changes to or adjustments in the conversion or exchange prices or rates and in the securities or other property receivable upon conversion or exchange; and

• material or special U.S. federal income tax considerations, if any.

The applicable prospectus supplement and any related free writing prospectus that we may authorize to be provided to you may also add, update or change any of the information contained in this prospectus or in the documents we have incorporated by reference.

THIS PROSPECTUS MAY NOT BE USED TO CONSUMMATE A SALE OF SECURITIES UNLESS IT IS ACCOMPANIED BY A PROSPECTUS SUPPLEMENT.

We may sell the securities directly to investors or to or through agents, underwriters or dealers. We and our agents or underwriters, reserve the right to accept or reject all or part of any proposed purchase of securities. If we do offer securities to or through agents or underwriters, we will include in the applicable prospectus supplement:

• the names of those agents or underwriters;

• applicable fees, discounts and commissions to be paid to them;

• details regarding overallotment options, if any; and

• the estimated net proceeds to us.

Common Stock

We may issue shares of our common stock from time to time. The holders of our common stock are entitled to one vote for each share held of record on all matters submitted to a vote of stockholders. Subject to the rights of the holders of preferred stock, the holders of common stock are entitled to receive such dividends and distributions as

3

may be declared by our board of directors out of legally available funds. In the event of a liquidation, dissolution or winding up, upon the completion of the distributions required with respect to any series of preferred stock that may then be outstanding, our remaining assets legally available for distribution to stockholders shall be distributed on an equal priority, pro rata basis to the holders of common stock. No shares of our common stock are subject to redemption or have preemptive rights to purchase additional shares of our common stock. In this prospectus, we have summarized certain general features of the common stock under the heading “Description of Capital Stock—Common Stock.” We urge you, however, to read the applicable prospectus supplement (and any related free writing prospectus that we may authorize to be provided to you) related to any common stock being offered.

Preferred Stock

We may issue shares of our preferred stock from time to time, in one or more series. Our certificate of incorporation provides that our board of directors has the authority, without action by the stockholders, to designate and issue up to 10,000,000 shares of preferred stock in one or more classes or series and to fix the powers, rights, preferences, privileges and restrictions of each class or series of preferred stock, including dividend rights, conversion rights, voting rights, redemption privileges, liquidation preferences and the number of shares constituting any class or series, which may be greater than the rights of the holders of the common stock. Convertible preferred stock will be convertible into our common stock or exchangeable for other securities. Conversion may be mandatory or at your option and would be at prescribed conversion rates.

If we sell any series of preferred stock under this prospectus, we will fix the designations, voting powers, preferences and rights of the preferred stock of each series we issue under this prospectus, as well as the qualifications, limitations or restrictions thereof, in the certificate of designation relating to that series. We will file as an exhibit to the registration statement of which this prospectus is a part, or will incorporate by reference from reports that we file with the SEC, the form of any certificate of designation that contains the terms of the series of preferred stock we are offering. In this prospectus, we have summarized certain general features of the preferred stock under the heading “Description of Capital Stock—Preferred Stock.” We urge you, however, to read the applicable prospectus supplement (and any related free writing prospectus that we may authorize to be provided to you) related to the series of preferred stock being offered, as well as the complete certificate of designation that contains the terms of the applicable series of preferred stock.

Debt Securities

We may issue debt securities from time to time, in one or more series, as either senior or subordinated debt or as senior or subordinated convertible debt. The senior debt securities will rank equally with any other unsecured and unsubordinated debt. The subordinated debt securities will be subordinate and junior in right of payment, to the extent and in the manner described in the instrument governing the debt, to all of our senior indebtedness. Convertible or exchangeable debt securities will be convertible into or exchangeable for our common stock or our other securities. Conversion or exchange may be mandatory or optional (at our option or the holders’ option) and would be at prescribed conversion or exchange prices.

The debt securities will be issued under an indenture that we will enter into with a national banking association or other eligible party, as trustee. In this prospectus, we have summarized certain general features of the debt securities under the heading “Description of Debt Securities.” We urge you, however, to read the applicable prospectus supplement (and any related free writing prospectus that we may authorize to be provided to you) related to the series of debt securities being offered, as well as the complete indenture and any supplemental indentures that contain the terms of the debt securities. We have filed the form of indenture as an exhibit to the registration statement of which this prospectus is a part, and supplemental indentures and forms of debt securities containing the terms of the debt securities being offered will be filed as exhibits to the registration statement of which this prospectus is a part or will be incorporated by reference from reports that we file with the SEC.

Warrants

We may issue warrants for the purchase of common stock, preferred stock and/or debt securities in one or more series. We may issue warrants independently or in combination with common stock, preferred stock and/or debt securities offered by any prospectus supplement. In this prospectus, we have summarized certain general features of

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the warrants under the heading “Description of Warrants.” We urge you, however, to read the applicable prospectus supplement (and any related free writing prospectus that we may authorize to be provided to you) related to the particular series of warrants being offered, as well as the form of warrant and/or the warrant agreement and warrant certificate, as applicable, that contain the terms of the warrants. We have filed the forms of the warrant agreements and forms of warrant certificates containing the terms of the warrants that we may offer as exhibits to the registration statement of which this prospectus is a part. We will file as exhibits to the registration statement of which this prospectus is a part, or will incorporate by reference from reports that we file with the SEC, the form of warrant and/or the warrant agreement and warrant certificate, as applicable, that contain the terms of the particular series of warrants we are offering, and any supplemental agreements, before the issuance of such warrants.

Warrants may be issued under a warrant agreement that we enter into with a warrant agent. We will indicate the name and address of the warrant agent, if any, in the applicable prospectus supplement relating to a particular series of warrants.

Use of Proceeds

Except as described in any applicable prospectus supplement or in any free writing prospectuses we have authorized for use in connection with a specific offering, we currently intend to use the net proceeds from the sale of the securities offered by us hereunder, if any, for working capital and general corporate purposes. We will set forth in the applicable prospectus supplement or free writing prospectus our intended use for the net proceeds received from the sale of any securities sold pursuant to the prospectus supplement or free writing. See “Use of Proceeds” in this prospectus.

Nasdaq Capital Market Listing

Our common stock and public warrants are listed on the Nasdaq Capital Market under the symbols “RGTI” and “RGTIW,” respectively. The applicable prospectus supplement will contain information, where applicable, as to other listings, if any, on the Nasdaq Capital Market or any other securities market or other exchange of the securities covered by the applicable prospectus supplement.

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RISK FACTORS

Investing in our securities involves a high degree of risk. Before deciding whether to invest in our securities, you should consider carefully the risks and uncertainties described under the section titled “Risk Factors” contained in the applicable prospectus supplement and any related free writing prospectus, and discussed under the section titled “Risk Factors” contained in our most recent Annual Report on Form 10-K and in our most recent Quarterly Report on Form 10-Q, as well as any amendments thereto reflected in subsequent filings with the SEC, which are incorporated by reference into this prospectus in their entirety, together with other information in this prospectus, the documents incorporated by reference and any free writing prospectus that we may authorize for use in connection with a specific offering. The risks described in these documents are not the only ones we face, but those that we consider to be material. There may be other unknown or unpredictable economic, business, competitive, regulatory or other factors that could have material adverse effects on our future results. Past financial performance may not be a reliable indicator of future performance, and historical trends should not be used to anticipate results or trends in future periods. If any of these risks actually occur, our business, financial condition, results of operations or cash flow could be harmed. This could cause the trading price of our securities to decline, resulting in a loss of all or part of your investment. Please also read carefully the section below titled “Cautionary Note Regarding Forward-Looking Statements.”

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CAUTIONARY NOTE REGARDING FORWARD-LOOKING STATEMENTS

This prospectus and the documents we have filed with the SEC that are incorporated by reference herein and any prospectus supplement delivered with this prospectus may contain forward-looking statements within the meaning of Section 27A of the Securities Act of 1933, as amended (the “Securities Act”), and Section 21E of the Securities Exchange Act of 1934, as amended (the “Exchange Act”). This includes, without limitation, statements regarding the financial position, business strategy and the plans and objectives of management for future operations. These statements constitute projections, forecasts and forward-looking statements, and are not guarantees of performance. We have based these forward-looking statements on our current expectations and projections about future events. Any statements that refer to projections, forecasts or other characterizations of future events or circumstances are forward-looking statements. In some cases, you can identify forward-looking statements by terminology such as “anticipate,” “believe,” “continue,” “could,” “estimate,” “expect,” “intends,” “may,” “might,” “plan,” “possible,” “potential,” “predict,” “project,” “should,” “could,” “will,” “would” or the negative of such terms or other similar expressions.

These forward-looking statements are subject to known and unknown risks, uncertainties and assumptions about us that may cause our actual results, levels of activity, performance or achievements to be materially different from any future results, levels of activity, performance or achievements expressed or implied by such forward-looking statements. Except as otherwise required by applicable law, we disclaim any duty to update any forward-looking statements, all of which are expressly qualified by the statements in this section, to reflect events or circumstances after the date of this prospectus.

We caution you that these forward-looking statements are subject to numerous risks and uncertainties, most of which are difficult to predict and many of which are beyond our control. Forward-looking statements in this prospectus may include, for example, statements about:

• the sufficiency of our cash resources, our expectation that we will need to raise additional capital by early 2025, including any additional sales of common stock through our Common Stock Purchase Agreement with B. Riley or from other sources, and our ability to raise additional capital when needed and on attractive terms;

• our ability to achieve milestones, and/or technological advancements, including with respect to executing on our technology roadmap and developing practical applications;

• the potential of quantum computing and estimated market size and market growth including with respect to our long-term business strategy for quantum computing as a service (“Quantum Computing as a Service,” or “QCaaS”);

• the success of our partnerships and collaborations;

• our ability to accelerate our development of multiple generations of quantum processors;

• customer concentration and the risk that a significant portion of our revenue currently depends on contracts with the public sector;

• the outcome of any legal proceedings that may be instituted against us or others with respect to the merger transaction between Rigetti Holdings, Inc. and Supernova Partners Acquisition Company II, Ltd. that was completed on March 2, 2022 (the “Business Combination”) or other matters;

• our ability to execute on our business strategy, including monetization of our products;

• our financial performance, growth rate and market opportunity;

• our ability to maintain compliance with standards relating to the listing of our common stock and public warrants on the Nasdaq Capital Market, and the potential liquidity and trading of such securities;

• the ability to recognize the anticipated benefits of the Business Combination, which may be affected by, among other things, competition, our ability to grow and manage growth profitably, maintain relationships with customers and suppliers and retain our management and key employees;

• costs related to operating as a public company;

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• our ability to remediate the material weaknesses in, and establish and maintain, effective internal controls over financial reporting;

• changes in applicable laws or regulations;

• the possibility that we may be adversely affected by other economic, business, or competitive factors;

• the evolution of the markets in which we compete;

• our ability to implement our strategic initiatives, expansion plans and continue to innovate our existing services;

• unfavorable conditions in our industry, the global economy or global supply chain (including any supply chain impacts from the ongoing military conflicts involving Russia and Ukraine and sanctions related thereto and the state of war between Israel and Hamas and the potential larger regional conflict), including inflation and financial and credit market fluctuations;

• changes in applicable laws or regulations;

• our success in retaining or recruiting, or changes required in, our officers, key employees or directors;

• our estimates regarding expenses, profitability, future revenue, capital requirements and needs for additional financing;

• our ability or decisions to expand or maintain our existing customer base;

• macroeconomic conditions, including worsening global economic conditions, disruptions to and volatility and uncertainty in the credit and financial markets, increases in inflation and interest rates, and recent and potential future disruptions in access to bank deposits or lending commitments due to bank failures, on the foregoing; and

• use of proceeds from offerings of our securities under this prospectus.

The forward-looking statements contained in this prospectus are based on our current expectations and beliefs concerning future developments and their potential effects on us. There can be no assurance that future developments affecting us will be those that we have anticipated. These forward-looking statements involve a number of risks, uncertainties (some of which are beyond our control) or other assumptions that may cause actual results or performance to be materially different from those expressed or implied by these forward-looking statements. These risks and uncertainties include, but are not limited to, those described in the section titled “Risk Factors” and elsewhere in this prospectus. Should one or more of these risks or uncertainties materialize, or should any of our assumptions prove incorrect, actual results may vary in material respects from those projected in these forward-looking statements. We undertake no obligation to update or revise any forward-looking statements, whether as a result of new information, future events or otherwise, except as required by law. We discuss in greater detail many of these risks under the section titled “Risk Factors” contained in the applicable prospectus supplement, in any free writing prospectuses we may authorize for use in connection with a specific offering, and in our most recent Annual Report on Form 10-K and in our most recent Quarterly Report on Form 10-Q, as well as any amendments thereto reflected in subsequent filings with the SEC, which are incorporated by reference into this prospectus in their entirety. Also, these forward-looking statements represent our estimates and assumptions only as of the date of the document containing the applicable statement. Unless required by law, we undertake no obligation to update or revise any forward-looking statements to reflect new information or future events or developments. You should read this prospectus, any applicable prospectus supplement, together with the documents we have filed with the SEC that are incorporated by reference and any free writing prospectus that we may authorize for use in connection with a specific offering completely and with the understanding that our actual future results may be materially different from what we expect. We qualify all of the forward-looking statements in the foregoing documents by these cautionary statements.

In addition, statements that “we believe” and similar statements reflect our beliefs and opinions on the relevant subject. These statements are based upon information available to us as of the date of this prospectus, and while we believe such information forms a reasonable basis for such statements, such information may be limited or incomplete, and our statements should not be read to indicate that we have conducted an exhaustive inquiry into, or review of, all potentially available relevant information. These statements are inherently uncertain and you are cautioned not to unduly rely upon these statements.

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USE OF PROCEEDS

Except as described in any applicable prospectus supplement or in any free writing prospectuses we have authorized for use in connection with a specific offering, we currently intend to use the net proceeds for working capital and general corporate purposes.

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DESCRIPTION OF CAPITAL STOCK

The following summary description is based on our certificate of incorporation (the “Certificate of Incorporation”), our amended and restated bylaws (the “Bylaws”) and the applicable provisions of the Delaware General Corporation Law (the “DGCL”). This information may not be complete in all respects and is qualified entirely by reference to the provisions of our Certificate of Incorporation and Bylaws, and is qualified in its entirety by reference to our Certificate of Incorporation and our Bylaws which are incorporated by reference into the registration statement of which this prospectus is a part.

General

Our Certificate of Incorporation authorizes the issuance of 1,000,000,000 shares of common stock, $0.0001 par value per share, and 10,000,000 shares of preferred stock, $0.0001 par value per share. As of December 6, 2023, there were approximately 145,014,572 shares of common stock and no shares of preferred stock issued and outstanding.

Common Stock

Voting Rights

Each holder of common stock is entitled to one (1) vote for each share of common stock held of record by such holder on all matters voted upon by our stockholders, provided, however, that, except as otherwise required in the Certificate of Incorporation or by applicable law, the holders of common stock will not be entitled to vote on any amendment to the Certificate of Incorporation that alters or changes the powers, preferences, rights or other terms of one or more outstanding series of preferred stock if the holders of such affected series are entitled, either separately or together with the holders of one or more other such series, to vote thereon pursuant to the Certificate of Incorporation (including any certificate of designation relating to any series of preferred stock) or pursuant to the DGCL. When a quorum is present, the affirmative vote of a majority of the voting power of the shares present in person, by remote communication, if applicable, or represented by proxy at the meeting and entitled to vote generally on the subject matter is required to take action, unless otherwise specified by law, the Bylaws or the Certificate of Incorporation, and except for the election of directors, which is determined by a plurality vote. There are no cumulative voting rights.

Dividend Rights

Subject to the rights of the holders of preferred stock and any other provisions of the Certificate of Incorporation, as it may be amended from time to time, holders of common stock will be entitled to receive such dividends and other distributions in cash, stock or property of the Company when, as and if declared thereon by the Board, in its discretion, from time to time out of assets or funds of the Company legally available therefor.

Rights upon Liquidation, Dissolution and Winding-Up

Subject to the rights of holders of preferred stock, in the event of any liquidation, dissolution or winding up of our affairs, whether voluntary or involuntary, after payment or provision for payment of our debts and any other payments required by law and amounts payable upon shares of preferred stock ranking senior to the shares of common stock upon such dissolution, liquidation or winding up, if any, the Company’s remaining net assets will be distributed to the holders of common stock and the holders of any other class or series of capital stock ranking equally with the common stock upon such dissolution, liquidation or winding up, equally on a per share basis.

Other Rights

There are no redemption or sinking fund provisions applicable to the common stock. The rights, preferences and privileges of holders of common stock will be subject to those of the holders of preferred stock that the Company may issue in the future.

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Election of Directors

Our Board is divided into three classes, Class I, Class II and Class III, with members of each class serving staggered three-year terms with only one class of directors being elected in each year. Under the Bylaws, the election of directors is determined by plurality vote.

Preferred Stock

Under our Certificate of Incorporation, our board of directors may, without further action by our stockholders, fix the rights, preferences, privileges and restrictions of up to an aggregate of 10,000,000 shares of preferred stock in one or more series and authorize their issuance. These rights, preferences and privileges could include dividend rights, conversion rights, voting rights, terms of redemption, liquidation preferences and the number of shares constituting any series or the designation of such series, any or all of which may be greater than the rights of common stock. Any issuance of preferred stock could adversely affect the voting power of holders of common stock and the likelihood that such holders would receive dividend payments and payments on liquidation. In addition, the issuance of preferred stock could have the effect of delaying, deterring or preventing a change of control or other corporate action.

We will fix the designations, voting powers, preferences and rights of the preferred stock of each series we issue under this prospectus, as well as the qualifications, limitations or restrictions thereof, in the certificate of designation relating to that series. We will file as an exhibit to the registration statement of which this prospectus is a part, or will incorporate by reference from reports that we file with the SEC, the form of any certificate of designation that contains the terms of the series of preferred stock we are offering. We will describe in the applicable prospectus supplement the terms of the series of preferred stock being offered, including, to the extent applicable:

• the title and stated value;

• the number of shares we are offering;

• the liquidation preference per share;

• the purchase price;

• the dividend rate, period and payment date and method of calculation for dividends;

• whether dividends will be cumulative or non-cumulative and, if cumulative, the date from which dividends will accumulate;

• the procedures for any auction and remarketing, if applicable;

• the provisions for a sinking fund, if applicable;

• the provisions for redemption or repurchase, if applicable, and any restrictions on our ability to exercise those redemption and repurchase rights;

• any listing of the preferred stock on any securities exchange or market;

• whether the preferred stock will be convertible into our common stock, and, if applicable, the conversion price, or how it will be calculated, and the conversion period;

• whether the preferred stock will be exchangeable into debt securities, and, if applicable, the exchange price, or how it will be calculated, and the exchange period;

• voting rights of the preferred stock;

• preemptive rights, if any;

• restrictions on transfer, sale or other assignment;

• whether interests in the preferred stock will be represented by depositary shares;

• a discussion of any material or special U.S. federal income tax considerations applicable to the preferred stock;

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• the relative ranking and preferences of the preferred stock as to dividend rights and rights if we liquidate, dissolve or wind up our affairs;

• any limitations on the issuance of any class or series of preferred stock ranking senior to or on a parity with the series of preferred stock as to dividend rights and rights if we liquidate, dissolve or wind up our affairs; and

• any other specific terms, preferences, rights or limitations of, or restrictions on, the preferred stock.

The transfer agent for each series of preferred stock will be described in the applicable prospectus supplement.

Certain Anti-Takeover Provisions of Delaware Law and our Second Amended and Restated Certificate of Incorporation and Bylaws

Section 203 of the Delaware General Corporation Law

We are subject to Section 203 of the DGCL, which generally prohibits a publicly held Delaware corporation from engaging in any business combination with any interested stockholder for a period of three years after the date that such stockholder became an interested stockholder, with the following exceptions:

• before such date, the board of directors of the corporation approved either the business combination or the transaction that resulted in the stockholder becoming an interested stockholder;

• upon completion of the transaction that resulted in the stockholder becoming an interested stockholder, the interested stockholder owned at least 85% of the voting stock of the corporation outstanding at the time the transaction began, excluding for purposes of determining the voting stock outstanding, but not the outstanding voting stock owned by the interested stockholder, those shares owned (1) by persons who are directors and also officers and (2) employee stock plans in which employee participants do not have the right to determine confidentially whether shares held subject to the plan will be tendered in a tender or exchange offer; or

• on or after such date, the business combination is approved by the board of directors and authorized at an annual or special meeting of the stockholders, and not by written consent, by the affirmative vote of at least 66 2/3% of the outstanding voting stock that is not owned by the interested stockholder.

In general, Section 203 defines a “business combination” to include the following:

• any merger or consolidation involving the corporation and the interested stockholder;

• any sale, transfer, pledge or other disposition of 10% or more of the assets of the corporation involving the interested stockholder;

• subject to certain exceptions, any transaction that results in the issuance or transfer by the corporation of any stock of the corporation to the interested stockholder;

• any transaction involving the corporation that has the effect of increasing the proportionate share of the stock or any class or series of the corporation beneficially owned by the interested stockholder; or

• the receipt by the interested stockholder of the benefit of any loans, advances, guarantees, pledges or other financial benefits by or through the corporation.

In general, Section 203 defines an “interested stockholder” as an entity or person who, together with the person’s affiliates and associates, beneficially owns or within three years prior to the time of determination of interested stockholder status did own, 15% or more of the outstanding voting stock of the corporation.

A Delaware corporation may “opt out” of these provisions with an express provision in its original certificate of incorporation or an express provision in an amended and restated certificate of incorporation or amended and restated bylaws resulting from a stockholders’ amendment approved by at least a majority of the outstanding voting shares. We have not opted out of these provisions. As a result, mergers or other takeover or change in control attempts of us may be discouraged or prevented.

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Certificate of Incorporation and Bylaws

Among other things, our Certificate of Incorporation and Bylaws:

• providing for a classified board of directors with staggered, three-year terms;

• the ability of the Board to issue up to 10,000,000 shares of preferred stock, including “blank check” preferred stock, with any rights, preferences and privileges as they may designate, including the right to approve an acquisition or other change of control;

• provide that the authorized number of directors may be changed only by resolution of the Board;

• provide that, subject to the rights of the holders of any series of preferred stock, any individual director or directors may be removed only with cause by the affirmative vote of the holders of at least 66 2/3% of the voting power of all of the then-outstanding shares of our capital stock entitled to vote generally in the election of directors, voting together as a single class;

• provide that all vacancies, including newly created directorships, may, except as otherwise required by law, be filled by the affirmative vote of a majority of directors then in office, even if less than a quorum;

• require that any action to be taken by our stockholders must be effected at a duly called annual or special meeting of stockholders and not be taken by written consent or electronic transmission;

• provide that stockholders seeking to present proposals before a meeting of stockholders or to nominate candidates for election as directors at a meeting of stockholders must provide advance notice in writing, and also specify requirements as to the form and content of a stockholder’s notice;

• provide that special meetings of our stockholders may be called by the chairperson of the Board, the chief executive officer or by the Board pursuant to a resolution adopted by a majority of the total number of authorized directors; and

• not provide for cumulative voting rights, therefore allowing the holders of a majority of the shares of common stock entitled to vote in any election of directors to elect all of the directors standing for election, if they should so choose.

The combination of these provisions will make it more difficult for the existing stockholders to replace our board of directors as well as for another party to obtain control of us by replacing our board of directors. Because our board of directors has the power to retain and discharge its officers, these provisions could also make it more difficult for existing stockholders or another party to effect a change in management. In addition, the authorization of undesignated preferred stock makes it possible for our board of directors to issue preferred stock with voting or other rights or preferences that could impede the success of any attempt to change our control.

These provisions are intended to enhance the likelihood of continued stability in the composition of our board of directors and its policies and to discourage coercive takeover practices and inadequate takeover bids. These provisions are also designed to reduce our vulnerability to hostile takeovers and to discourage certain tactics that may be used in proxy fights. However, such provisions could have the effect of discouraging others from making tender offers for our shares and may have the effect of delaying changes in our control or management. As a consequence, these provisions may also inhibit fluctuations in the market price of our stock.

Exclusive Forum of Certain Actions

The Certificate of Incorporation requires, unless we consent in writing to the selection of an alternative forum, that Court of Chancery of the State of Delaware (or, if and only if the Court of Chancery of the State of Delaware lacks subject matter jurisdiction, any state court located within the State of Delaware or, if and only if all such state courts lack subject matter jurisdiction, the federal district court for the District of Delaware) and any appellate court therefrom is the sole and exclusive forum for the following types of actions or proceedings under Delaware statutory

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or common law: (i) derivative actions brought on behalf of the Company; (ii) actions against current or former directors, officers or other employees or stockholders of the Company for breach of fiduciary duty to the Company or the Company’s stockholders; (iii) actions against the Company or any current or former director, officer or other employee or stockholder of the Company, arising out of or pursuant to any provision of the DGCL or the Certificate of Incorporation or the Bylaws,: (iv) actions to interpret, apply, enforce or determine the validity of the Certificate of Incorporation or the Bylaws; (v) actions as to which the DGCL confers jurisdiction on the Court of Chancery of the State of Delaware; and (vi) actions against the Company or any current or former director, officer or other employee or stockholder of the Company, governed by the internal-affairs doctrine of the law of the State of Delaware, in all cases to the fullest extent permitted by law and subject to the court having personal jurisdiction over the indispensable parties named as defendants. However, this provision will not apply to claims or actions brought to enforce a duty or liability created by the Securities Act or Exchange Act, or any other claim for which the federal courts have exclusive jurisdiction. The Certificate of Incorporation further provides that unless we consent in writing to the selection of an alternative forum, to the fullest extent permitted by law, the federal district courts of the United States of America will be the exclusive forum for the resolution of any complaint asserting a cause or causes of action arising under the Securities Act, including all causes of action asserted against any defendant named in such complaint. Additionally, the Certificate of Incorporation provides that any person or entity holding, owning or otherwise acquiring any interest in any of our securities shall be deemed to have notice of and consented to these provisions.

Although we believe this provision benefits us by providing increased consistency in the application of Delaware law in the types of lawsuits to which it applies, the provision may have the effect of discouraging lawsuits against our directors and officers. Additionally, we cannot be certain that a court will decide that this provision is either applicable or enforceable, and if a court were to find the choice of forum provision contained in the amended and restated certificate of incorporation to be inapplicable or unenforceable in an action, we may incur additional costs associated with resolving such action in other jurisdictions, which could harm our business, operating results and financial condition.

Amendment to Certificate of Incorporation and Bylaws

The DGCL provides generally that the affirmative vote of a majority of the outstanding stock entitled to vote on amendments to a corporation’s certificate of incorporation or bylaws is required to approve such amendment, unless a corporation’s certificate of incorporation or bylaws, as the case may be, requires a greater percentage.

The Certificate of Incorporation provides, in addition to the votes required by law, that the following provisions therein may be amended, altered, repealed or rescinded only by the affirmative of the holders of at least sixty-six and two-thirds percent (66 2/3%) of the voting power of all of the then-outstanding shares of capital stock of common stock and preferred stock entitled to vote generally in the election of directors, voting together as a single class, including provisions regarding the classified board structure, the size of the Board, the election and removal of directors to the Board, the filling of vacancies, the limited liability of directors and officers of Rigetti and exclusive forums for certain actions.

The Bylaws may be amended or repealed (A) by the affirmative vote of a majority of the entire Board then in office, without the assent or vote of any stockholder (subject to any bylaw requiring the affirmative vote of a larger percentage of the members of the Board) or (B) without the approval of the Board, by the affirmative vote of the holders of any class or series of stock of Rigetti required by law or by the Certificate of Incorporation, such action by stockholders requiring the affirmative vote of the holders of at least sixty-six and two-thirds percent (66 2/3%) of the voting power of all of the then-outstanding shares of the capital stock of Rigetti entitled to vote generally in the election of directors, voting together as a single class.

Listing

Our common stock and public warrants are listed on the Nasdaq Capital Market under the symbols “RGTI” and “RGTIW,” respectively. The applicable prospectus supplement will contain information, where applicable, as to any other listing, if any, on the Nasdaq Global Select Market or any securities market or other exchange of the preferred stock covered by such prospectus supplement.

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Transfer Agent and Registrar

The transfer agent and registrar for our common stock is American Stock Transfer & Trust Company.

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DESCRIPTION OF DEBT SECURITIES

We may issue debt securities from time to time, in one or more series, as either senior or subordinated debt or as senior or subordinated convertible debt. While the terms we have summarized below will apply generally to any debt securities that we may offer under this prospectus, we will describe the particular terms of any debt securities that we may offer in more detail in the applicable prospectus supplement. The terms of any debt securities offered under a prospectus supplement may differ from the terms described below. Unless the context requires otherwise, whenever we refer to the indenture, we also are referring to any supplemental indentures that specify the terms of a particular series of debt securities.

We will issue the debt securities under the indenture that we will enter into with the trustee named in the indenture. The indenture will be qualified under the Trust Indenture Act of 1939, as amended, or the Trust Indenture Act. We have filed the form of indenture as an exhibit to the registration statement of which this prospectus is a part, and supplemental indentures and forms of debt securities containing the terms of the debt securities being offered will be filed as exhibits to the registration statement of which this prospectus is a part or will be incorporated by reference from reports that we file with the SEC.

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

General

The indenture does not limit the amount of debt securities that we may issue. It provides that we may issue debt securities up to the principal amount that we may authorize and may be in any currency or currency unit that we may designate. Except for the limitations on consolidation, merger and sale of all or substantially all of our assets contained in the indenture, the terms of the indenture do not contain any covenants or other provisions designed to give holders of any debt securities protection against changes in our operations, financial condition or transactions involving us.

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

We will describe in the applicable prospectus supplement the terms of the series of debt securities being offered, including:

• the title of the series of debt securities;

• any limit upon the aggregate principal amount that may be issued;

• the maturity date or dates;

• the form of the debt securities of the series;

• the applicability of any guarantees;

• whether or not the debt securities will be secured or unsecured, and the terms of any secured debt;

• whether the debt securities rank as senior debt, senior subordinated debt, subordinated debt or any combination thereof, and the terms of any subordination;

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• if the price (expressed as a percentage of the aggregate principal amount thereof) at which such debt securities will be issued is a price other than the principal amount thereof, the portion of the principal amount thereof payable upon declaration of acceleration of the maturity thereof, or if applicable, the portion of the principal amount of such debt securities that is convertible into another security or the method by which any such portion shall be determined;

• the interest rate or rates, which may be fixed or variable, or the method for determining the rate and the date interest will begin to accrue, the dates interest will be payable and the regular record dates for interest payment dates or the method for determining such dates;

• our right, if any, to defer payment of interest and the maximum length of any such deferral period;

• if applicable, the date or dates after which, or the period or periods during which, and the price or prices at which, we may, at our option, redeem the series of debt securities pursuant to any optional or provisional redemption provisions and the terms of those redemption provisions;

• the date or dates, if any, on which, and the price or prices at which we are obligated, pursuant to any mandatory sinking fund or analogous fund provisions or otherwise, to redeem, or at the holder’s option to purchase, the series of debt securities and the currency or currency unit in which the debt securities are payable;

• the denominations in which we will issue the series of debt securities, if other than denominations of $1,000 and any integral multiple thereof;

• any and all terms, if applicable, relating to any auction or remarketing of the debt securities of that series and any security for our obligations with respect to such debt securities and any other terms which may be advisable in connection with the marketing of debt securities of that series;

• whether the debt securities of the series shall be issued in whole or in part in the form of a global security or securities;

• the terms and conditions, if any, upon which such global security or securities may be exchanged in whole or in part for other individual securities; and the depositary for such global security or securities;

• if applicable, the provisions relating to conversion or exchange of any debt securities of the series and the terms and conditions upon which such debt securities will be so convertible or exchangeable, including the conversion or exchange price, as applicable, or how it will be calculated and may be adjusted, any mandatory or optional (at our option or the holders’ option) conversion or exchange features, the applicable conversion or exchange period and the manner of settlement for any conversion or exchange;

• if other than the full principal amount thereof, the portion of the principal amount of debt securities of the series which shall be payable upon declaration of acceleration of the maturity thereof;

• additions to or changes in the covenants applicable to the particular debt securities being issued, including, among others, the consolidation, merger or sale covenant;

• additions to or changes in the events of default with respect to the securities and any change in the right of the trustee or the holders to declare the principal, premium, if any, and interest, if any, with respect to such securities to be due and payable;

• additions to or changes in or deletions of the provisions relating to covenant defeasance and legal defeasance;

• additions to or changes in the provisions relating to satisfaction and discharge of the indenture;

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• additions to or changes in the provisions relating to the modification of the indenture both with and without the consent of holders of debt securities issued under the indenture;

• the currency of payment of debt securities if other than U.S. dollars and the manner of determining the equivalent amount in U.S. dollars;

• whether interest will be payable in cash or additional debt securities at our or the holders’ option and the terms and conditions upon which the election may be made;

• the terms and conditions, if any, upon which we will pay amounts in addition to the stated interest, premium, if any and principal amounts of the debt securities of the series to any holder that is not a “United States person” for federal tax purposes;

• any restrictions on transfer, sale or assignment of the debt securities of the series; and

• any other specific terms, preferences, rights or limitations of, or restrictions on, the debt securities, any other additions or changes in the provisions of the indenture, and any terms that may be required by us or advisable under applicable laws or regulations.

Conversion or Exchange Rights

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

Consolidation, Merger or Sale

Unless we provide otherwise in the prospectus supplement applicable to a particular series of debt securities, the indenture will not contain any covenant that restricts our ability to merge or consolidate, or sell, convey, transfer or otherwise dispose of our assets as an entirety or substantially as an entirety. However, any successor to or acquirer of such assets (other than a subsidiary of ours) must assume all of our obligations under the indenture or the debt securities, as appropriate.

Events of Default under the Indenture

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

• if we fail to pay any installment of interest on any series of debt securities, as and when the same shall become due and payable, and such default continues for a period of 90 days; provided, however, that a valid extension of an interest payment period by us in accordance with the terms of any indenture supplemental thereto shall not constitute a default in the payment of interest for this purpose;

• if we fail to pay the principal of, or premium, if any, on any series of debt securities as and when the same shall become due and payable whether at maturity, upon redemption, by declaration or otherwise, or in any payment required by any sinking or analogous fund established with respect to such series; provided, however, that a valid extension of the maturity of such debt securities in accordance with the terms of any indenture supplemental thereto shall not constitute a default in the payment of principal or premium, if any;

• if we fail to observe or perform any other covenant or agreement contained in the debt securities or the indenture, other than a covenant specifically relating to another series of debt securities, and our failure continues for 90 days after we receive written notice of such failure, requiring the same to be remedied and stating that such is a notice of default thereunder, from the trustee or holders of at least 25% in aggregate principal amount of the outstanding debt securities of the applicable series; and

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• if specified events of bankruptcy, insolvency or reorganization occur.

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

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

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

• the direction so given by the holder is not in conflict with any law or the applicable indenture; and

• subject to its duties under the Trust Indenture Act, the trustee need not take any action that might involve it in personal liability or might be unduly prejudicial to the holders not involved in the proceeding.

• A holder of the debt securities of any series will have the right to institute a proceeding under the indenture or to appoint a receiver or trustee, or to seek other remedies only if:

• the holder has given written notice to the trustee of a continuing event of default with respect to that series;

• the holders of at least 25% in aggregate principal amount of the outstanding debt securities of that series have made written request,

• such holders have offered to the trustee indemnity satisfactory to it against the costs, expenses and liabilities to be incurred by the trustee in compliance with the request; and

• the trustee does not institute the proceeding, and does not receive from the holders of a majority in aggregate principal amount of the outstanding debt securities of that series other conflicting directions within 90 days after the notice, request and offer.

These limitations do not apply to a suit instituted by a holder of debt securities if we default in the payment of the principal, premium, if any, or interest on, the debt securities.

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

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Modification of Indenture; Waiver

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

• to cure any ambiguity, defect or inconsistency in the indenture or in the debt securities of any series;

• to comply with the provisions described above under “Description of Debt Securities—Consolidation, Merger or Sale;”

• to provide for uncertificated debt securities in addition to or in place of certificated debt securities;

• to add to our covenants, restrictions, conditions or provisions such new covenants, restrictions, conditions or provisions for the benefit of the holders of all or any series of debt securities, to make the occurrence, or the occurrence and the continuance, of a default in any such additional covenants, restrictions, conditions or provisions an event of default or to surrender any right or power conferred upon us in the indenture;

• to add to, delete from or revise the conditions, limitations, and restrictions on the authorized amount, terms, or purposes of issue, authentication and delivery of debt securities, as set forth in the indenture;

• to make any change that does not adversely affect the interests of any holder of debt securities of any series in any material respect;

• to provide for the issuance of and establish the form and terms and conditions of the debt securities of any series as provided above under “Description of Debt Securities—General” to establish the form of any certifications required to be furnished pursuant to the terms of the indenture or any series of debt securities, or to add to the rights of the holders of any series of debt securities;

• to evidence and provide for the acceptance of appointment under any indenture by a successor trustee; or

• to comply with any requirements of the SEC in connection with the qualification of any indenture under the Trust Indenture Act.

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

• extending the fixed maturity of any debt securities of any series;

• reducing the principal amount, reducing the rate of or extending the time of payment of interest, or reducing any premium payable upon the redemption of any series of any debt securities; or

• reducing the percentage of debt securities, the holders of which are required to consent to any amendment, supplement, modification or waiver.

Discharge

Each indenture provides that we can elect to be discharged from our obligations with respect to one or more series of debt securities, except for specified obligations, including obligations to:

• provide for payment;

• register the transfer or exchange of debt securities of the series;

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• replace stolen, lost or mutilated debt securities of the series;

• pay principal of and premium and interest on any debt securities of the series;

• maintain paying agencies;

• hold monies for payment in trust;

• recover excess money held by the trustee;

• compensate and indemnify the trustee; and

• appoint any successor trustee.

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

Form, Exchange and Transfer

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

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

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

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

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

• issue, register the transfer of, or exchange any debt securities of that series during a period beginning at the opening of business 15 days before the day of mailing of a notice of redemption of any debt securities that may be selected for redemption and ending at the close of business on the day of the mailing; or

• register the transfer of or exchange any debt securities so selected for redemption, in whole or in part, except the unredeemed portion of any debt securities we are redeeming in part.

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Information Concerning the Trustee

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

Payment and Paying Agents

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

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

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

Governing Law

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

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DESCRIPTION OF WARRANTS

The following description, together with the additional information we may include in any applicable prospectus supplement and free writing prospectus, summarizes the material terms and provisions of the warrants that we may offer under this prospectus, which may consist of warrants to purchase common stock, preferred stock or debt securities and may be issued in one or more series. Warrants may be offered independently or in combination with common stock, preferred stock or debt securities offered by any prospectus supplement. While the terms we have summarized below will apply generally to any warrants that we may offer under this prospectus, we will describe the particular terms of any series of warrants in more detail in the applicable prospectus supplement. The following description of warrants will apply to the warrants offered by this prospectus unless we provide otherwise in the applicable prospectus supplement. The applicable prospectus supplement for a particular series of warrants may specify different or additional terms.

We have filed forms of the warrant agreements and forms of warrant certificates containing the terms of the warrants that may be offered as exhibits to the registration statement of which this prospectus is a part. We will file as exhibits to the registration statement of which this prospectus is a part, or will incorporate by reference from reports that we file with the SEC, the form of warrant and/or the warrant agreement and warrant certificate, as applicable, that contain the terms of the particular series of warrants we are offering, and any supplemental agreements, before the issuance of such warrants. The following summaries of material terms and provisions of the warrants are subject to, and qualified in their entirety by reference to, all the provisions of the form of warrant and/or the warrant agreement and warrant certificate, as applicable, and any supplemental agreements applicable to a particular series of warrants that we may offer under this prospectus. We urge you to read the applicable prospectus supplement related to the particular series of warrants that we may offer under this prospectus, as well as any related free writing prospectus, and the complete form of warrant and/or the warrant agreement and warrant certificate, as applicable, and any supplemental agreements, that contain the terms of the warrants.

General

We will describe in the applicable prospectus supplement the terms of the series of warrants being offered, including:

• the title of such securities;

• the offering price and aggregate number of warrants offered;

• the currency for which the warrants may be purchased;

• if applicable, the designation and terms of the securities with which the warrants are issued and the number of warrants issued with each such security or each principal amount of such security;

• if applicable, the date on and after which the warrants and the related securities will be separately transferable;

• if applicable, the minimum or maximum amount of such warrants which may be exercised at any one time;

• in the case of warrants to purchase debt securities, the principal amount of debt securities purchasable upon exercise of one warrant and the price at, and currency in which, this principal amount of debt securities may be purchased upon such exercise;

• in the case of warrants to purchase common stock or preferred stock, the number of shares of common stock or preferred stock, as the case may be, purchasable upon the exercise of one warrant and the price at which these shares may be purchased upon such exercise;

• the effect of any merger, consolidation, sale or other disposition of our business on the warrant agreements and the warrants;

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• the terms of any rights to redeem or call the warrants;

• the terms of any rights to force the exercise of the warrants;

• any provisions for changes to or adjustments in the exercise price or number of securities issuable upon exercise of the warrants;

• the dates on which the right to exercise the warrants will commence and expire;

• the manner in which the warrant agreements and warrants may be modified;

• a discussion of any material or special U.S. federal income tax considerations of holding or exercising the warrants;

• the terms of the securities issuable upon exercise of the warrants; and

• any other specific terms, preferences, rights or limitations of or restrictions on the warrants.

Before exercising their warrants, holders of warrants will not have any of the rights of holders of the securities purchasable upon such exercise, including:

• in the case of warrants to purchase debt securities, the right to receive payments of principal of, or premium, if any, or interest on, the debt securities purchasable upon exercise or to enforce covenants in the applicable indenture; or

• in the case of warrants to purchase common stock or preferred stock, the right to receive dividends, if any, or, payments upon our liquidation, dissolution or winding up or to exercise voting rights, if any.

Exercise of Warrants

Each warrant will entitle the holder to purchase the securities that we specify in the applicable prospectus supplement at the exercise price that we describe in the applicable prospectus supplement. The warrants may be exercised as set forth in the prospectus supplement relating to the warrants offered. Unless we otherwise specify in the applicable prospectus supplement, warrants may be exercised at any time up to the close of business on the expiration date set forth in the prospectus supplement relating to the warrants offered thereby. After the close of business on the expiration date, unexercised warrants will become void.

Upon receipt of payment and the warrant or warrant certificate, as applicable, properly completed and duly executed at the corporate trust office of the warrant agent, if any, or any other office, including ours, indicated in the prospectus supplement, we will, as soon as practicable, issue and deliver the securities purchasable upon such exercise. If less than all of the warrants (or the warrants represented by such warrant certificate) are exercised, a new warrant or a new warrant certificate, as applicable, will be issued for the remaining warrants. If we so indicate in the applicable prospectus supplement, holders of the warrants may surrender securities as all or part of the exercise price for warrants.

Governing Law

Unless we otherwise specify in the applicable prospectus supplement, the warrants and any warrant agreements will be governed by and construed in accordance with the laws of the State of New York.

Enforceability of Rights by Holders of Warrants

Each warrant agent, if any, will act solely as our agent under the applicable warrant agreement and will not assume any obligation or relationship of agency or trust with any holder of any warrant. A single bank or trust company may act as warrant agent for more than one issue of warrants. A warrant agent will have no duty or responsibility in case

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of any default by us under the applicable warrant agreement or warrant, including any duty or responsibility to initiate any proceedings at law or otherwise, or to make any demand upon us. Any holder of a warrant may, without the consent of the related warrant agent or the holder of any other warrant, enforce by appropriate legal action its right to exercise, and receive the securities purchasable upon exercise of, its warrants.

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LEGAL OWNERSHIP OF SECURITIES

We may issue securities in registered form or in the form of one or more global securities. We describe global securities in greater detail below. We refer to those persons who have securities registered in their own names on the books that we or any applicable trustee, depositary or warrant agent maintain for this purpose as the “holders” of those securities. These persons are the legal holders of the securities. We refer to those persons who, indirectly through others, own beneficial interests in securities that are not registered in their own names, as “indirect holders” of those securities. As we discuss below, indirect holders are not legal holders, and investors in securities issued in book-entry form or in street name will be indirect holders.

Book-Entry Holders

We may issue securities in book-entry form only, as we will specify in the applicable prospectus supplement. This means securities may be represented by one or more global securities registered in the name of a financial institution that holds them as depositary on behalf of other financial institutions that participate in the depositary’s book-entry system. These participating institutions, which are referred to as participants, in turn, hold beneficial interests in the securities on behalf of themselves or their customers.

Only the person in whose name a security is registered is recognized as the holder of that security. Securities issued in global form will be registered in the name of the depositary or its participants. Consequently, for securities issued in global form, we will recognize only the depositary as the holder of the securities, and we will make all payments on the securities to the depositary. The depositary passes along the payments it receives to its participants, which in turn pass the payments along to their customers who are the beneficial owners. The depositary and its participants do so under agreements they have made with one another or with their customers; they are not obligated to do so under the terms of the securities.

As a result, investors in a global security will not own securities directly. Instead, they will own beneficial interests in a global security, through a bank, broker or other financial institution that participates in the depositary’s book-entry system or holds an interest through a participant. As long as the securities are issued in global form, investors will be indirect holders, and not legal holders, of the securities.

Street Name Holders

We may terminate a global security or issue securities in non-global form. In these cases, investors may choose to hold their securities in their own names or in “street name.” Securities held by an investor in street name would be registered in the name of a bank, broker or other financial institution that the investor chooses, and the investor would hold only a beneficial interest in those securities through an account he or she maintains at that institution.

For securities held in street name, we or any applicable trustee or depositary will recognize only the intermediary banks, brokers and other financial institutions in whose names the securities are registered as the holders of those securities, and we or any applicable trustee or depositary will make all payments on those securities to them. These institutions pass along the payments they receive to their customers who are the beneficial owners, but only because they agree to do so in their customer agreements or because they are legally required to do so. Investors who hold securities in street name will be indirect holders, not holders, of those securities.

Legal Holders

Our obligations, as well as the obligations of any applicable trustee and of any third parties employed by us or a trustee, run only to the legal holders of the securities. We do not have obligations to investors who hold beneficial interests in global securities, in street name or by any other indirect means. This will be the case whether an investor chooses to be an indirect holder of a security or has no choice because we are issuing the securities only in global form.

For example, once we make a payment or give a notice to the holder, we have no further responsibility for the payment or notice even if that holder is required, under agreements with depositary participants or customers or by

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law, to pass it along to the indirect holders but does not do so. Similarly, we may want to obtain the approval of the holders to amend an indenture, to relieve us of the consequences of a default or of our obligation to comply with a particular provision of the indenture or for other purposes. In such an event, we would seek approval only from the holders, and not the indirect holders, of the securities. Whether and how the holders contact the indirect holders is up to the holders.

Special Considerations for Indirect Holders

If you hold securities through a bank, broker, or other financial institution, either in book-entry form because the securities are represented by one or more global securities or in street name, you should check with your own institution to find out:

• the performance of third-party service providers;

• how it handles securities payments and notices;

• whether it imposes fees or charges;

• how it would handle a request for the holders’ consent, if ever required;

• whether and how you can instruct it to send you securities registered in your own name so you can be a holder, if that is permitted in the future;

• how it would exercise rights under the securities if there were a default or other event triggering the need for holders to act to protect their interests; and

• if the securities are in book-entry form, how the depositary’s rules and procedures will affect these matters.

Global Securities

A global security is a security that represents one or any other number of individual securities held by a depositary. Generally, all securities represented by the same global securities will have the same terms.

Each security issued in book-entry form will be represented by a global security that we deposit with and register in the name of a financial institution or its nominee that we select. The financial institution that we select for this purpose is called the depositary. Unless we specify otherwise in the applicable prospectus supplement, DTC will be the depositary for all securities issued in book-entry form.

A global security may not be transferred to or registered in the name of anyone other than the depositary, its nominee or a successor depositary, unless special termination situations arise. We describe those situations below under “Special Situations When a Global Security Will Be Terminated”. As a result of these arrangements, the depositary, or its nominee, will be the sole registered owner and holder of all securities represented by a global security, and investors will be permitted to own only beneficial interests in a global security. Beneficial interests must be held by means of an account with a broker, bank or other financial institution that in turn has an account with the depositary or with another institution that does. Thus, an investor whose security is represented by a global security will not be a holder of the security, but only an indirect holder of a beneficial interest in the global security.

If the prospectus supplement for a particular security indicates that the security will be issued in global form only, then the security will be represented by a global security at all times unless and until the global security is terminated. If termination occurs, we may issue the securities through another book-entry clearing system or decide that the securities may no longer be held through any book-entry clearing system.

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Special Considerations for Global Securities

The rights of an indirect holder relating to a global security will be governed by the account rules of the investor’s financial institution and of the depositary, as well as general laws relating to securities transfers. We do not recognize an indirect holder as a holder of securities and instead deal only with the depositary that holds the global security.

If securities are issued only in the form of a global security, an investor should be aware of the following:

• an investor cannot cause the securities to be registered in his or her name, and cannot obtain non-global certificates for his or her interest in the securities, except in the special situations we describe below;

• an investor will be an indirect holder and must look to his or her own bank or broker for payments on the securities and protection of his or her legal rights relating to the securities, as we describe above;

• an investor may not be able to sell interests in the securities to some insurance companies and to other institutions that are required by law to own their securities in non-book-entry form;

• an investor may not be able to pledge his or her interest in a global security in circumstances where certificates representing the securities must be delivered to the lender or other beneficiary of the pledge in order for the pledge to be effective;

• the depositary’s policies, which may change from time to time, will govern payments, transfers, exchanges and other matters relating to an investor’s interest in a global security;

• we and any applicable trustee have no responsibility for any aspect of the depositary’s actions or for its records of ownership interests in a global security, nor do we or any applicable trustee supervise the depositary in any way;

• the depositary may, and we understand that DTC will, require that those who purchase and sell interests in a global security within its book-entry system use immediately available funds, and your broker or bank may require you to do so as well; and

• financial institutions that participate in the depositary’s book-entry system, and through which an investor holds its interest in a global security, may also have their own policies affecting payments, notices and other matters relating to the securities.

There may be more than one financial intermediary in the chain of ownership for an investor. We do not monitor and are not responsible for the actions of any of those intermediaries.

Special Situations When a Global Security Will Be Terminated

In a few special situations described below, the global security will terminate and interests in it will be exchanged for physical certificates representing those interests. After that exchange, the choice of whether to hold securities directly or in street name will be up to the investor. Investors must consult their own banks or brokers to find out how to have their interests in securities transferred to their own name, so that they will be direct holders. We have described the rights of holders and street name investors above.

Unless we provide otherwise in the applicable prospectus supplement, the global security will terminate when the following special situations occur:

• if the depositary notifies us that it is unwilling, unable or no longer qualified to continue as depositary for that global security and we do not appoint another institution to act as depositary within 90 days;

• if we notify any applicable trustee that we wish to terminate that global security; or

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• if an event of default has occurred with regard to securities represented by that global security and has not been cured or waived.

The applicable prospectus supplement may also list additional situations for terminating a global security that would apply only to the particular series of securities covered by the applicable prospectus supplement. When a global security terminates, the depositary, and not we or any applicable trustee, is responsible for deciding the names of the institutions that will be the initial direct holders.

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PLAN OF DISTRIBUTION

We may sell the securities from time to time pursuant to underwritten public offerings, direct sales to the public, negotiated transactions, block trades or a combination of these methods. We may sell the securities to or through one or more underwriters or dealers (acting as principal or agent), through agents, or directly to one or more purchasers. We may distribute the securities from time to time in one or more transactions:

• at a fixed price or prices, which may be changed;

• at market prices prevailing at the time of sale;

• at prices related to such prevailing market prices; or

• at negotiated prices.

We will describe the terms of the offering of the securities and the specific plan of distribution in a prospectus supplement or supplements to this prospectus, any related free writing prospectus that we may authorize to be provided to you, an amendment to the registration statement of which this prospectus is a part or other filings we make with the SEC under the Exchange Act that are incorporated by reference. Such description may include, to the extent applicable:

• the name or names of any underwriters, dealers, agents or other purchasers;

• the purchase price of the securities or other consideration therefor, and the proceeds, if any, we will receive from the sale;

• any options to purchase additional shares or other options under which underwriters, dealers, agents or other purchasers may purchase additional securities from us;

• any agency fees or underwriting discounts and other items constituting agents’ or underwriters’ compensation;

• any public offering price;

• any discounts or concessions allowed or reallowed or paid to dealers; and

• any securities exchange or market on which the securities may be listed.

We may also sell equity securities covered by this registration statement in an “at the market” offering as defined in Rule 415(a)(4) under the Securities Act. Such offering may be made into an existing trading market for such securities in transactions at other than a fixed price on or through the facilities of the Nasdaq Capital Market or any other securities exchange or quotation or trading service on which such securities may be listed, quoted or traded at the time of sale. Such at the market offerings, if any, may be conducted by underwriters acting as principal or agent.

Only underwriters named in the prospectus supplement will be underwriters of the securities offered by the prospectus supplement. Dealers and agents participating in the distribution of the securities may be deemed to be underwriters, and compensation received by them on resale of the securities may be deemed to be underwriting discounts. If such dealers or agents were deemed to be underwriters, they may be subject to statutory liabilities under the Securities Act.

If underwriters are used in the sale, they will acquire the securities for their own account and may resell the securities from time to time in one or more transactions at a fixed public offering price or at varying prices determined at the time of sale. The obligations of the underwriters to purchase the securities will be subject to the conditions set forth in the applicable underwriting agreement. We may offer the securities to the public through underwriting

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syndicates represented by managing underwriters or by underwriters without a syndicate. Subject to certain conditions, the underwriters will be obligated to purchase all of the securities offered by the prospectus supplement, other than securities covered by any option to purchase additional shares or other option. If a dealer is used in the sale of securities, we, or an underwriter, will sell the securities to the dealer, as principal. The dealer may then resell the securities to the public at varying prices to be determined by the dealer at the time of resale. To the extent required, we will set forth in the prospectus supplement the name of the dealer and the terms of the transaction. Any public offering price and any discounts or concessions allowed or reallowed or paid to dealers may change from time to time. We may use underwriters, dealers or agents with whom we have a material relationship. In such case, we will describe in the prospectus supplement the name of the underwriter, dealer or agent and the nature of any such relationship.

We may sell securities directly or through agents we designate from time to time. We will name any agent involved in the offering and sale of securities and we will describe any commissions payable to the agent in the prospectus supplement. Unless the prospectus supplement states otherwise, the agent will act on a best-efforts basis for the period of its appointment.

We may authorize agents or underwriters to solicit offers by certain types of institutional investors to purchase 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. We will describe the conditions to these contracts and the commissions we must pay for solicitation of these contracts in the prospectus supplement.

We may provide agents, dealers and underwriters with indemnification against civil liabilities, including liabilities under the Securities Act, or contribution with respect to payments that the agents or dealers or underwriters may make with respect to these liabilities. Agents, dealers and underwriters or their affiliates may engage in transactions with, or perform services for us in the ordinary course of business.

All securities we may offer, other than common stock, will be new issues of securities with no established trading market. Any underwriters may make a market in these securities, but will not be obligated to do so and may discontinue any market making at any time without notice. We cannot guarantee the liquidity of the trading markets for any securities.

Any underwriter may be granted an option to purchase additional shares, and engage in stabilizing transactions, short-covering transactions and penalty bids in accordance with Regulation M under the Exchange Act. An underwriter’s option to purchase additional shares involves sales in excess of the offering size, which create a short position. Stabilizing transactions permit bids to purchase the underlying security so long as the stabilizing bids do not exceed a specified maximum price. Syndicate-covering or other short-covering transactions involve purchases of the securities, either through exercise of the option to purchase additional shares or in the open market after the distribution is completed, to cover short positions. Penalty bids permit the underwriters to reclaim a selling concession from a dealer when the securities originally sold by the dealer are purchased in a stabilizing or covering transaction to cover short positions. Those activities may cause the price of the securities to be higher than it would otherwise be. If commenced, the underwriters may discontinue any of the activities at any time. These transactions may be effected on any exchange or over-the-counter market or otherwise.

Any underwriters, dealers or agents that are qualified market makers on the Nasdaq Capital Market may engage in passive market making transactions in our common stock on the Nasdaq Capital Market in accordance with Regulation M under the Exchange Act, during the business day prior to the pricing of the 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.

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LEGAL MATTERS

The validity of any securities offered by this prospectus will be passed upon for us by Cooley LLP.

EXPERTS

The consolidated financial statements as of December 31, 2022 and 2021, and for the year ended December 31, 2022 and eleven months ended December 31, 2021, incorporated by reference in this Prospectus and in the Registration Statement have been so incorporated in reliance on the report of BDO USA, LLP (n/k/a BDO USA, P.C.), an independent registered public accounting firm, incorporated herein by reference, given on the authority of said firm as experts in auditing and accounting.

WHERE YOU CAN FIND ADDITIONAL INFORMATION

This prospectus is part of the registration statement on Form S-3 we filed with the SEC under the Securities Act and does not contain all the information set forth or incorporated by reference in the registration statement. Whenever a reference is made in this prospectus to any of our contracts, agreements or other documents, the reference may not be complete and you should refer to the exhibits that are a part of the registration statement or the exhibits to the reports or other documents incorporated by reference into this prospectus for a copy of such contract, agreement or other document. Because we are subject to the information and reporting requirements of the Exchange Act, we file annual, quarterly and current reports, proxy statements and other information with the SEC. Our SEC filings are available to the public over the Internet at the SEC’s website at http://www.sec.gov. Our Annual Report on Form 10-K, Quarterly Reports on Form 10-Q and Current Reports on Form 8-K, including any amendments to those reports, and other information that we file with or furnish to the SEC pursuant to Section 13(a) or 15(d) of the Exchange Act can also be accessed free of charge on our website. These filings will be available as soon as reasonably practicable after we electronically file such material with, or furnish it to, the SEC. Our website address is www.rigetti.com. Information contained on or accessible through our website is not a part of this prospectus and is not incorporated by reference herein, and the inclusion of our website address in this prospectus is an inactive textual reference only.

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INCORPORATION OF CERTAIN INFORMATION BY REFERENCE

The SEC allows us to “incorporate by reference” information into this prospectus from other documents that we file with the SEC, which means that we can disclose important information to you by referring you to those documents. The information incorporated by reference is considered to be part of this prospectus and information we file later with the SEC will automatically update and supersede this information. Any statement contained in this prospectus or a previously filed document incorporated by reference will be deemed to be modified or superseded for purposes of this prospectus to the extent that a statement contained in this prospectus or a subsequently filed document incorporated by reference modifies or replaces that statement. The documents we are incorporating by reference as of their respective dates of filing are (in each case, other than those documents or the portions of those documents not deemed to be filed, including the portions of these documents that are furnished under Item 2.02 or Item 7.01 of a Current Report on Form 8-K, including any exhibits included with such Items):

• our Annual Report on Form 10-K for the year ended December 31, 2022, filed with the SEC on March 27, 2023;

• our Quarterly Reports on Form 10-Q for the quarter ended March 31, 2023, filed with the SEC on May 11, 2023, for the quarter ended June 30, 2023 filed with the SEC on August 10, 2023 and for the quarter ended September  30, 2023, filed with the SEC on November 9, 2023;

• our Current Reports on Form 8-K filed with the SEC on January  27, 2023, February  10, 2023, June  21, 2023, July  13, 2023 and October 31, 2023 and Current Report on Form 8-K/A filed with the SEC on February 16, 2023; and

• the description of securities contained in a Registration Statement on Form 8-A filed on March  1, 2022, as updated by Exhibit 4.4 to our Annual Report on Form 10-K for the year ended December 31, 2022, filed with the SEC on March 27, 2023, together with any amendment or report filed with the SEC for the purpose of updating such description.

Notwithstanding the foregoing, information furnished under Items 2.02 and 7.01 of any Current Report on Form 8-K, including the related exhibits under Item 9.01, is not incorporated by reference in this prospectus or any prospectus supplement.

All documents we subsequently file pursuant to Section 13(a), 13(c), 14 or 15(d) of the Exchange Act (in each case, other than those documents or the portions of those documents not deemed to be filed, including the portions of these documents that are furnished under Item 2.02 or Item 7.01 of a Current Report on Form 8-K, including any exhibits included with such Items), prior to the termination of this offering, including all such documents we may file after the date of the initial registration statement of which this prospectus forms a part and prior to the effectiveness of the registration statement, but excluding any information furnished to, rather than filed with, the SEC, will also be incorporated by reference into this prospectus and deemed to be part of this prospectus from the date of the filing of such reports and documents.

You may obtain any of the documents incorporated by reference in this prospectus from the SEC through the SEC’s website at the address provided above. You also may request a copy of any document incorporated by reference in this prospectus (excluding any exhibits to those documents, unless the exhibit is specifically incorporated by reference in this document), at no cost, by writing or telephoning us at the following address and phone number:

Rigetti Computing, Inc.

775 Heinz Avenue

Berkeley, California 94710

Attn: General Counsel

(510) 210-5550

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RIGETTI COMPUTING, INC.

Up to $100,000,000

Common Stock

PROSPECTUS SUPPLEMENT

Needham & Company      B. Riley Securities

March 15, 2024