Delivering on the Promise of the Human Proteome Nautilus Biotechnology Confidential – Do Not Distribute FEBRUARY 2021

Disclaimer 2 This presentation (“Presentation”) is provided for informational purposes only and has been prepared to assist interested parties in making their own evaluation with respect to the proposed business combination between ARYA Sciences Acquisition Corp III (“ARYA”) and Nautilus Biotechnology, Inc. (“Nautilus” or the “Company”) and related transactions (the “Potential Business Combination”) and for no other purpose. This information contained herein does not purport to be all-inclusive and none of ARYA, Nautilus, Jefferies LLC and Goldman Sachs & Co. LLC nor any of their respective affiliates nor any of its or their control persons, officers, directors, employees or representatives makes any representation or warranty, express or implied, as to the accuracy, completeness or reliability of the information contained in this Presentation. You should consult your own counsel and tax and financial advisors as to legal and related matters concerning the matters described herein, and, by accepting this Presentation, you confirm that you are not relying upon the information contained herein to make any decision. Without the express prior written consent of ARYA and Nautilus, this Presentation and any information contained within it may not be (i) reproduced (in whole or in part), (ii) copied at any time, (iii) used for any purpose other than your evaluation of the Potential Business Combination or (iv) provided to any other person, except your employees and advisors with a need to know who are advised of the confidentiality of the information.Forward Looking Statements. Certain statements in this Presentation may be considered forward-looking statements. Forward-looking statements generally relate to future events or ARYA’s or the Company’s future financial or operating performance. For example, statements concerning the following include forward-looking statements: the success and timing of product development activities; the Company’s expected commercial strategy; the ability to compete with other companies; the market size and growth potential and the ability to serve those markets; projected financial information; and the potential effects of the Potential Business Combination on the Company. In some cases, you can identify forward-looking statements by terminology such as “may,” “should,” “expect,” “intend,” “will,” “estimate,” “anticipate,” “believe,” “predict,” “potential,” or “continue,” or the negatives of these terms or variations of them or similar terminology. Such forward-looking statements are subject to risks, uncertainties, and other factors which could cause actual results to differ materially from those expressed or implied by such forward-looking statements. These forward-looking statements are based upon estimates and assumptions that, while considered reasonable by ARYA and its management, and Nautilus and its management, as the case may be, are inherently uncertain. New risks and uncertainties may emerge from time to time, and it is not possible to predict all risks and uncertainties. Factors that may cause actual results to differ materially from current expectations include, but are not limited to, risk related to Nautilus' ability to successfully develop and launch a commercial product and achieve market acceptance, raise additional funds that may be necessary for the operations of its business and product development, establish manufacturing capacity, manage its operations and potential growth and scale its business, protect its intellectual property, maintain effective internal controls, and the potential impact of the COVID-19 pandemic, as well as various other factors beyond management’s control including general economic conditions and other risks, uncertainties and factors set forth in the section entitled “Risk Factors” and “Cautionary Note Regarding Forward-Looking Statements” in ARYA’s final prospectus relating to its initial public offering, dated August 6, 2020, and other filings with the Securities and Exchange Commission (SEC). Nothing in this Presentation should be regarded as a representation by any person that the forward-looking statements set forth herein will be achieved or that any of the contemplated results of such forward-looking statements will be achieved. You should not place undue reliance on forward-looking statements in this Presentation, which speak only as of the date they are made and are qualified in their entirety by reference to the cautionary statements herein. Neither ARYA nor the Company undertakes any duty to update these forward-looking statements. Additional Information. In connection with the Potential Business Combination, ARYA intends to file with the SEC a registration statement on Form S-4 containing a preliminary proxy statement/prospectus of ARYA, and after the registration statement is declared effective, ARYA will mail a definitive proxy statement/prospectus relating to the proposed Business Combination to its shareholders. This Presentation does not contain all the information that should be considered concerning the proposed Business Combination and is not intended to form the basis of any investment decision or any other decision in respect of the Business Combination. ARYA’s shareholders and other interested persons are advised to read, when available, the preliminary proxy statement/prospectus and the amendments thereto and the definitive proxy statement/prospectus and other documents filed in connection with the proposed Business Combination, as these materials will contain important information about Nautilus, ARYA and the Business Combination. When available, the definitive proxy statement/prospectus and other relevant materials for the proposed Business Combination will be mailed to shareholders of ARYA as of a record date to be established for voting on the proposed Business Combination. Shareholders will also be able to obtain copies of the preliminary proxy statement/prospectus, the definitive proxy statement/prospectus and other documents filed with the SEC, without charge, once available, at the SEC’s website at www.sec.gov, or by directing a request to: ARYA Sciences Acquisition Corp III, 51 Astor Place, 10th Floor, New York, NY 10003.Participants in the Solicitation. ARYA, Nautilus and their respective directors and executive officers may be deemed participants in the solicitations of proxies from ARYA’s shareholders with respect to the proposed Business Combination. A list of the names of ARYA’s directors and executive officers and a description of their interests in ARYA is contained in ARYA’s final prospectus relating to its initial public offering, dated August 6, 2020, which was filed with the SEC and is available free of charge at the SEC’s website at www.sec.gov, or by directing a request to ARYA Sciences Acquisition Corp III, 51 Astor Place, 10th Floor, New York, NY 10003. Additional information regarding the interests of the participants in the solicitation of proxies from ARYA’s shareholders with respect to the proposed Business Combination will be contained in the proxy statement/prospectus for the proposed Business Combination when available.No Offer or Solicitation. This communication is for informational purposes only and does not constitute, or form a part of, an offer to sell or the solicitation of an offer to sell or an offer to buy or the solicitation of an offer to buy any securities, and there shall be no sale of securities, in any jurisdiction in which such offer, solicitation or sale would be unlawful prior to registration or qualification under the securities laws of any such jurisdiction. No offer of securities shall be made except by means of a prospectus meeting the requirements of Section 10 of the Securities Act of 1933, as amended, and otherwise in accordance with applicable law. Certain information contained in this Presentation relates to or is based on studies, publications, surveys and the Company’s own internal estimates and research. In addition, all of the market data included in this Presentation involves a number of assumptions and limitations, and there can be no guarantee as to the accuracy or reliability of such assumptions. Finally, while the Company believes its internal research is reliable, such research has not been verified by any independent source. This meeting and any information communicated at this meeting are strictly confidential and should not be discussed outside your organization.The reader shall not rely upon any statement, representation or warranty made by any other person, firm or corporation (including, without limitation, Jefferies LLC, Goldman Sachs & Co. LLC or any of their affiliates or control persons, officers, directors and employees) in making its investment or decision to invest in the Company. None of ARYA, the Company, Jefferies LLC or Goldman Sachs & Co. LLC, nor any of their respective affiliates nor any of its or their control persons, officers, directors, employees or representatives, shall be liable to the reader for any information set forth herein or any action taken or not taken by any reader, including any investment in shares of ARYA or the Company. Nautilus Biotechnology Confidential – Do Not Distribute

The proteome is among the most dynamic and valuable sources of biological insight.But current technologies lack the sensitivity, throughput, and ease of use required to address the needs of the biomedical community. Our Opportunity: To Revolutionize Biomedicine A fundamentally new approach is required to unlock this large opportunity in biological science. 3 Nautilus Biotechnology Confidential – Do Not Distribute

Nautilus Biotechnology Confidential – Do Not Distribute 4 Comprehensive proteomics analysis reimagined Single molecule proteomics platform with integrated machine learning designed to enable unprecedented sensitivity and scale $25+ Billion opportunity across proteomics and adjacent markets First pharma partnership with Genentech pioneering high impact technology application Founder-led organization and highly experienced leadership team Seeks to define a new gold standard for single molecule protein analysis The potential to change the trajectory of large existing markets At the heart of this effort is the desire to positively impact human health

Nautilus’ Revolutionary Innovation Was Not Possible Until NowRequired counter-intuitive science and the maturation of key disciplines Nautilus has innovated strengths in each discipline and then leveraged these strengths across those disciplines to achieve something designed to be revolutionary Founders’ diverse but complementary experiences enable them to address a challenge that others had notPursuing deep, hard science with an entrepreneurial mindset Life Sciences Physical Sciences & Engineering Computer & Data Science Nautilus Biotechnology Confidential – Do Not Distribute 5

Current Proteomics Ecosystem Nautilus Biotechnology Confidential – Do Not Distribute 6 Sample Collection BiopsyResectionBiofluid (Blood, CSF, Saliva)Laser-capture microdissectionCell sorting (FACS)Primary cell cultureStable cell line cultureXenograft Sample Extraction Chemical LysisGradient centrifugationHomogenizationMechanical LysisProtease and Phosphatase Inhibitors Protein Fractionation 1D and 2D gel electrophoresisIsoelectric focusingCapillary electrophoresisHPLC (Column chromatography)ImmunoprecipitationPulldowns with tagged proteinsCell surface labeling Active site labelingAffinity depletionAffinity enrichmentHydrophobic Interaction ChromatographyPhosphoflowGlycocaptureLectin affinity Digestion Trypic DigestionFASPSP3LysCNon-Enzymatic DigestionMicrowave Assisted DigestionOn-ChipMagnetic Particle ImmobilizedPore Immobilized Peptide Fractionation Ion-pairing reversed phase (RP-HPLC)Isoelectric focusing (IEF)Strong cation exchange (SCX)Weak anion exchange (WAX) Hydrophilic interaction (HILIC) Immobilized metal affinity (IMAC) Lectin affinity chromatography ImmunoprecipitationImmunoenrichmentSISCAPABiotinylationFractional diagonal chromatography Quantitative Labeling Metabolic labeling (SILAC, N)Chemical protein labeling (ICPL)Chemical peptide labeling (ICAT, cICAT, iTRAQ,TMT, methylation, esterification)Enzymatic peptide labeling (18O)Absolute quantification (AQUA, QconCAT) Sample Collection ElectrosprayMALDISELDIDESIDARTChip-BasedNanosprayMicrofluidic Mass Spectrometry TOFQQQTRAPEtc.SWATHDIAPRMSRMMRM Data Analysis for Protein Identification and Quantification ProteoWizardDatabase searchingDe novo sequencingPeptide mass fingerprinting (PMF) Accurate mass and time tag (AMT)…

Nautilus Biotechnology Confidential – Do Not Distribute 7 Mass Spec Solutions today only capture a fraction of the proteome from Blood or Cells There is No solution today to measure and quantify intact proteoforms Current Methods Can’t See Valuable Biology

8 We set out to re-invent proteomics from the ground up Setting Ambitious Goals: To Read and Quantify the Proteome and Proteoforms Nautilus Biotechnology Confidential – Do Not Distribute Easy to Use It Ultra-Sensitive Reproducible and Robust Rapid Run Time Integrated Complete Any Lab Can Run It Single Molecule Sensitivity Path to the Clinic Days not Weeks Sample to Insight No Missing Data

Integration of Breakthrough Innovations Across the PlatformDesigned to Allow Nautilus to Access Full Resolution Digital Proteomic Data 9 Sample Preparation& Deposition Instrumentation and Reagents for Single-Molecule Measurement Machine Learning-Based Analysis Digital Proteomic Data Protein Decoding Analytics Hyper-Dense Single Molecule Array Nautilus Biotechnology Confidential – Do Not Distribute

Simple, Rapid, and Robust Sample Preparation 10 Nautilus Biotechnology Confidential – Do Not Distribute Step 1 Blood or Cells or Step 4 Protein-Scaffold Conjugation Step 5 Protein-Scaffold Library for Deposition Step 3 Protein Labeling Key Takeaways: Rapid and Effective Chemistry Step 2 Protein Extraction & Cleanup > > > > >

Hyper-Dense Single Molecule Microarray Enables Deep, Sensitive Profiling 11 Nautilus Biotechnology Confidential – Do Not Distribute 1010 landing pads/Chip Sensitively measure down to 1 molecule in 1000 cellsExtreme sensitivity and wide dynamic range 106105104103102 10-1 101 103 105 Key Takeaways: 300nm > > > > >

High Resolution Multi-Cycle Imaging of Affinity Reagents Nautilus Biotechnology Confidential – Do Not Distribute 12 Integrated fluidics and imaging on instrumentDesigned to sensitively measure tens-of-billions of molecules across hundreds of cycles in approximately a day6 sample multiplexing, with potential for future expansion Key Takeaways: . . . > > > > >

Image Analysis Creates Digital Proteomic Data > > > > > Nautilus Biotechnology Confidential – Do Not Distribute Algorithmic processing & machine learning Data Compressed into Coordinate Binding Matrix Coordinate1,11,22,1 2,23,13,2 Binding sequence1,0,0…0,0,1…0,1,1…1,0,0…1,0,1…0,0,0… Image & data reduction (GPU) 13 Up to 20 Terabytes of Digital Protein data per runCloud-based data infrastructure to manage scaleSAAS data insights and analytics engine Key Takeaways:

Machine Learning Analytics in Cloud to Decode the Proteome Nautilus Biotechnology Confidential – Do Not Distribute > > > > > Coordinate Binding Matrix Coordinate1,11,22,1 2,23,13,2 Binding sequence1,0,0…0,0,1…0,1,1…1,0,0…1,0,1…0,0,0… 14 Coordinate1,11,22,1 2,23,13,2 IDENTITYEGFRTP53cMETPTENBRAFMEK Single Molecule Protein identifications Machine Learning architecture designed to enable broadscale proteomics profilingOn-instrument analysis and downstream analytics both improve as database grows Key Takeaways: quantity1068321.6x1051101212 IDENTITYEGFRTP53cMETPTENBRAFMEK Protein Quantifications

The Nautilus Platform is Highly Robust Nautilus Biotechnology Confidential – Do Not Distribute 15 Negligible loss of detection ability Negligible Protein Loss First Cycle Last Cycle

Unlocking the Human ProteomeProtein Decoding Using Multi-Affinity Probe Reagents Nautilus Biotechnology Confidential – Do Not Distribute 16

Capable of Comprehensive Decoding of the Human Proteome300 Cycle Multi-Affinity Probe Reagent System Run1 Nautilus Biotechnology Confidential – Do Not Distribute 17 Capable of Achieving >95% ProteomeCoverage 1Estimates based Nautilus computational analysis projecting the number of Nautilus designed short epitope probe binding events necessary to identify the SwissProt reference proteome.

Unlocking the Mystery of Proteoforms Nautilus Biotechnology Confidential – Do Not Distribute 18 DNA Protein Isoforms 1International Journal of Analytical Chemistry. 2016; 2016: 7436849. The Size of the Human Proteome: The Width and Depth, Elena A. Ponomarenko et al. The pattern of post-translational modifications is biologically important PTMs Methylation Phosphorylation Acetylation 20,000 genes 70,000 + Isoforms + = ~6,000,000+ PROTEOFORMS 1 Protein Isoforms + PTMS = Proteoforms ≠ ≠ ≠ . . .

Proteoform Quantification A Novel 2021 Technology Application Which drugs work and to what extent is defined not by just the total amount of PTMs and splice forms, but instead by how combinations of specific alterations operate together. Creating a technology to see these PTM patterns, and measure their relationship to one another, has the potential to hugely advance precision medicine.Dr. Ruedi Aebersold, Head of IMSB, Swiss Federal Institute of Technology (ETH) and Nautilus Scientific Advisory Board Member “ ” Nautilus Biotechnology Confidential – Do Not Distribute 19 ≠ Peptide-centric proteomics methods are unable to differentiate mixtures of proteoforms

Single Molecule Proteoform Detection Preserves Biological Information Nautilus Biotechnology Confidential – Do Not Distribute 20 > > > > > Key Takeaways: Sensitively quantify proteoform molecular heterogeneityOpen platform to apply virtually any high specificity reagent Cycle 1 Cycle 3 Cycle 5

Open Platform Technology Designed to be Compatible with Many Affinity Reagent Options 1BCC Research. Global Markets for Research Antibodies (2018).Nautilus Biotechnology Confidential – Do Not Distribute 21 Multi-affinity Aptamer Engineered Mini-protein Binder Designed to be Compatible withoff-the-shelf Antibodies Nautilus Reagents Designed in-house ~$3B Annual Research Antibody Market in 20221

Long-Term Transformation of Healthcare by Proteomics AI Powered Drug Discovery Clinical Diagnostics Precision & Personalized Medicine + Growth and Market Expansion Opportunity Large Market Opportunity Ready for Disruption Source: Allied Market Research: Proteomics Market Global Opportunity Analysis and Industry Forecast, 2020-2027, January 2021DeciBio, Life science research tools market size, growth and trends (2013-2021), July 2017Nautilus Biotechnology Confidential – Do Not Distribute 22 $25B Global Proteomics Market + Immediate Market Opportunity 50% BioPharma30% Applied Markets20% Academic & Research(Estimates based on Mass spectroscopy market) 12% CAGR(2020-2027)

Potential Markets & Applications Nautilus Biotechnology Confidential – Do Not Distribute 23 Multi-Omics & Systems Biology Proteoform Composition & Landscape Proteome Profiling (species agnostic) Biomarker & Drug Target Discovery Mechanism of Action Studies Toxicity Profiling and Prediction Longitudinal Monitoring of Proteome Dynamics Precision Medicine Development Drug Rescue & Repurposing Basic Sciences Translational Research Clinical Research & Development

Significant Target Milestones on Path to Comprehensive Proteomic ProfilingEach Step Represents a Potentially New and Unprecedented Advancement Nautilus Biotechnology Confidential – Do Not Distribute 24 LATE 2021 EARLY 2022 LATE 2022 MID OF 2023 LATE OF 2023 DATA PRODUCTION AT NAUTILUS CUSTOMER GENERATED DATA 2,500 Proteins/run Single MoleculeMulti-Cycle Read Out 10,000 Proteins/run Comprehensive Proteome Instrument Launch & Scale Up Projected Milestone Dates

Planned Three Phase Commercial Strategy 25 Application Development Instrument Pre-Sales 1 2 Nautilus Biotechnology Confidential – Do Not Distribute Partnerships & CollaborationsJointly publish dataMultiple high potential discovery and IP license optionsPharma validation and endorsement pre-commercial launch Early Access & POC EngagementsLeverage publications to drive awareness and customer demandLaunch Early Access Program to provide customers with broadscale profiling, pre-launch Engage in paid POC engagements to drive instrument pre-orders Direct SalesInstruments, Consumables, Software, SupportFull commercial launch with multi-year product roadmapClear path to near term system upgrades and enhancementsExecute commercial scale up Platform Launch 3

Nautilus Biotechnology Confidential – Do Not Distribute Planned Sales Model and Key Customer Segments Target Customers Land and Expand Sales Model 26 Pharmaceutical & Biotech B2B Diagnostic Service Partnerships Academic & Research Community Large-Scale Omics Core Laboratories Contract Research Organizations Add NewProducts Grow Workflows & Capacity Add New Research Groups Establish InitialBeachhead

2,500 Proteins/run Single MoleculeMulti-Cycle Read Out 10,000 Proteins/run Comprehensive Proteome Instrument Launch & Scale Up DATA PRODUCTION AT NAUTILUS CUSTOMER GENERATED DATA Each Milestone Expected to Create New Opportunities to PartnerEvery Step Represents a Potentially New and Unprecedented Advancement Nautilus Biotechnology Confidential – Do Not Distribute 27 LATE 2021 EARLY 2022 LATE 2022 MID OF 2023 LATE OF 2023 Early Access & POC EngagementsExpand applications, demonstrate discovery potential Instrument & ConsumablesEarly Access and Launch Establish Collaborations & PartnershipsEngage early, create value through data and publications Projected Milestone Dates

2,500 Proteins/run Single MoleculeMulti-Cycle Read Out 10,000 Proteins/run Comprehensive Proteome Instrument Launch & Scale Up DATA PRODUCTION AT NAUTILUS CUSTOMER GENERATED DATA Nautilus Biotechnology Confidential – Do Not Distribute 28 Establish Collaborations & PartnershipsEngage early, create value through data and publications TARGET OUTCOME:Technology Validation and Endorsement Broadening engagement TARGET: Pharma / Biotech and Influential Academic Sites STRATEGY:Create Foundational Publications, Demonstrate Utility, Build Confidence Early Access & POC EngagementsExpand applications, demonstrate discovery potential Instrument & ConsumablesEarly Access and Launch LATE 2021 EARLY 2022 LATE 2022 MID OF 2023 LATE OF 2023 Each Milestone Expected to Create New Opportunities to PartnerEvery Step Represents a Potentially New and Unprecedented Advancement Projected Milestone Dates

2,500 Proteins/run Single MoleculeMulti-Cycle Read Out 10,000 Proteins/run Comprehensive Proteome Instrument Launch & Scale Up DATA PRODUCTION AT NAUTILUS CUSTOMER GENERATED DATA Nautilus Biotechnology Confidential – Do Not Distribute 29 TARGET: Advanced Proteomic Laboratories STRATEGY:Seed Market for Instrument Pre-Sales, Expand Application Value & Utility TARGET OUTCOME:Accelerate Demand for Instrumentation, Create Pre-Launch Customer Pipeline Early Access & POC EngagementsExpand applications, demonstrate discovery potential Establish Collaborations & PartnershipsEngage early, create value through data and publications Instrument & ConsumablesEarly Access and Launch LATE 2021 EARLY 2022 LATE 2022 MID OF 2023 LATE OF 2023 Each Milestone Expected to Create New Opportunities to PartnerEvery Step Represents a Potentially New and Unprecedented Advancement Projected Milestone Dates

2,500 Proteins/run Single MoleculeMulti-Cycle Read Out 10,000 Proteins/run Comprehensive Proteome Instrument Launch & Scale Up DATA PRODUCTION AT NAUTILUS CUSTOMER GENERATED DATA Nautilus Biotechnology Confidential – Do Not Distribute 30 Instrument & Consumables TARGET: Create Diverse Initial Customer Base STRATEGY:Establish Presence in Multiple Markets, Set Up Expansion Opportunities TARGET OUTCOME:Scale of Data Production & Value Across Markets Catalyzes Business Growth Early Access & POC EngagementsExpand applications, demonstrate discovery potential LATE 2021 EARLY 2022 LATE 2022 MID OF 2023 LATE OF 2023 Establish Collaborations & PartnershipsEngage early, create value through data and publications Each Milestone Expected to Create New Opportunities to PartnerEvery Step Represents a Potentially New and Unprecedented Advancement Projected Milestone Dates

Planned Strategic Elements of the Platform Designed to Create Competitive Advantage in the Field Nautilus Biotechnology Confidential – Do Not Distribute 31 First to Market with Novel Detection Platform Highly Disruptive Technology Immense Data Production Capacity Proven Commercial Model Diversified and Recurring Revenue Sources Immense Data Production Capacity First Mover Advantage in a Large and Expanding Market Unlocks new sources of primary biological information Drives Discovery Potential and Technology UbiquityData is an Asset Average Selling Price Enables Efficient Direct Sales Model (>$1M ASP)Start in North America and then start building international footprint with distribution partners PartnershipsInstrumentationConsumablesService and SupportSoftware as a Service

Nautilus and Genentech Collaboration Nautilus Biotechnology Confidential – Do Not Distribute Signed a pilot study Research Collaboration Agreement in December 2020.We are collaborating with Genentech using the Nautilus system to analyze and map the proteoform landscape of a Genentech protein target of interest.Aim to submit results for publication late 2021. Nautilus Technology at Work: Proteoform patterns are hypothesized to be critical players directly involved in molecular disease progression.A pattern of detected protein modifications could itself become a biomarker, and it may also provide new insight for how to interrupt a molecular disease pathway. 32

Patent Portfolio Summary(as of January 21, 2021) Nautilus Biotechnology Confidential – Do Not Distribute 33 SAMPLE PREPARATION1 Patent Family SINGLE MOLECULE MICROARRAY2 Patent Families PROBES & IMAGING5 Patent Families MACHINE LEARNING & ANALYTICS2 Patent Families IMAGE ANALYSIS1 Patent Family Overall Process 3 Patent Families (3 Allowed US Patents) > > > > >

Leadership 34 Sujal PatelFounder & CEO Anna MowryCFO Parag MallickFounder & CSO Nick NelsonSVP, CBO Investors Scientific Advisory Board Ruedi Aebersold, PhDProf. Systems Biology,Institute of Molecular Systems Biology in ETH Zurich (IMSB) Lee Hartwell, PhDPresident and Director Emeritus, Fred Hutchinson Cancer Research CenterNobel Laureate Joshua LaBaer, MD, PhDExecutive Director,Biodesign Institute atArizona State University Board of Directors Parag Mallick, PhDFounder,Chief Scientist Stuart NagaeDirector,Vulcan Capital Farzad NazemAngel Investor,Former EVP Engineering & CTO, Yahoo Vijay Pande, PhDGeneral Partner,Andreessen Horowitz Sujal PatelFounder,Chief Executive Officer Matthew Posard, ChairFounding Principal, Explore DNA; Former SVP & Head of Global Sales, Illumina Subra SankarSVP, R&D John MurphyHead of Global IP Chris BlessingtonVP, Corp. Marketing Mary GodwinVP, Operations Nautilus Biotechnology Confidential – Do Not Distribute Matt McIlwainManaging Director,Madrona Venture Group Melissa EpperlyCFO,Zentalis Pharmaceuticals

Nautilus Biotechnology Confidential – Do Not Distribute 35 Target Range as % of Revenue GROSS MARGIN 70% R&D OpEx 15-20% SG&A OpEx 20-25% OPERATING INCOME 25-30% Long Term Financial Targets

Nautilus Biotechnology Confidential – Do Not Distribute WhyNautilus? We believe that humanity needs a dramatic acceleration of drug development and that a bold scientific leap is required to make possible a new world of precision and personalized medicine. To deliver, we need to radically reinvent proteomics, a large untapped opportunity in biological science today. 36 Proven Team, Driven to Win Potential for Revolutionizing Biomedicine Designed to address what the market wants – the proteome at single molecule scale Aligned with investors on long-term shareholder value creation Significant New Potential Market Opportunity

37 Merging with ARYA III Provides us with a direct path to IPO and greater access to capitalEnables us to go public in one step vs. the typical two or three step venture backed private rounds, and provides access to a strong market backdrop today to properly fund and grow our businessProvides us an investment structure for a broad set of specialized public investors while meaningfully reducing market riskCapitalizes us with $385m+(1) through the merger and PIPE to fund long-term development of our proprietary proteomics platformExpected to provide cash runway to achieve key catalysts and commercialization Accelerates development of our unique proteomics platform and the expansion of new resources across scientific, engineering, and commercial teamsInstates a premier investor base and a long-term partnership with PerceptiveEstablishes a broad syndicate of banks and research analysts that follow our stock post closing Nautilus Biotechnology Confidential – Do Not Distribute (1) Projected cash balance from cash held in trust and expected PIPE financing of $200m plus expected cash to balance sheet in Q2 2021.

38 Terms of Transaction Nautilus Biotechnology Confidential – Do Not Distribute Pro Forma Valuation Sources of Funds (1) Uses of Funds (1) Pro Forma Shares Outstanding 129,187 Implied Share Price $ 10.00 PF Equity Value $ 1,291,865 Less: PF Cash $ (386,500) Implied PF Enterprise Value $ 905,365 Equity Issued to Nautilus Equityholders(3) $ 900,000 Estimated Transaction Fees & Expenses(4) $ 22,000 Remaining Cash (Balance Sheet) $ 386,500 Total Uses of Funds $ 1,308,500 Pro Forma Ownership(3) Cash Held in Trust $ 149,500(2) Nautilus Equityholder Rollover(3) $ 900,000 PIPE Proceeds $ 200,000 Total Sources of Funds $ 1,308,500 (1) As per closing anticipated in Q2 2021; (2) Assumes no shareholder redemptions and based on implied share price of $10 per share; not adjusted for interest; (3) Allocation of equity consideration to Nautilus equityholders based on TSM; (4) Fees and expenses for both Nautilus and SPAC, includes deferred underwriting fees from ARYA III’s IPO. Shares and $ in thousands (other than share price) Shares % ARYA III Sponsor + Perceptive 12,650 10% o/w Perceptive Nautilus Shares 2,913 2% o/w Sponsor Promote Shares 3,738 3% o/w Sponsor Private Placement Shares 499 0% o/w Perceptive PIPE Shares 5,500 4% Public Shareholders (excl. ARYA III Sponsor) 14,950 12% Current Nautilus Equityholders (ex-Perceptive) 90,886 70% o/w Existing Nautilus Shareholder PIPE Shares 3,800 3% Third Party PIPE Investors 10,700 8% Totals 129,187 100%

Thank You Nautilus Biotechnology Confidential – Do Not Distribute

Appendix Nautilus Biotechnology Confidential – Do Not Distribute

41 Balance Sheet Nautilus Biotechnology Confidential – Do Not Distribute Note: Financial data above are unaudited and subject to change based upon completion of a PCAOB audit for the fiscal year ended December 31, 2019. Cash, cash equivalents, and short-term investments total $76.7M as of December 31, 2020. Such amount is unaudited and subject to change based upon completion of a PCAOB audit for the fiscal year ended December 31, 2020.The preliminary financial data included herein has been prepared by, and is the responsibility of Nautilus' management. Nautilus' independent registered public accounting firm has not audited, reviewed, compiled, or applied agreed-upon procedures with respect to the preliminary financial data. Accordingly, Nautilus's independent registered public accounting firm does not express an opinion or any other form of assurance with respect thereto.

42 Statement of Operations Nautilus Biotechnology Confidential – Do Not Distribute Note: Financial data above are unaudited and subject to change based upon completion of a PCAOB audit for the fiscal year ended December 31, 2019. The preliminary financial data included herein has been prepared by, and is the responsibility of Nautilus' management. Nautilus' independent registered public accounting firm has not audited, reviewed, compiled, or applied agreed-upon procedures with respect to the preliminary financial data. Accordingly, Nautilus's independent registered public accounting firm does not express an opinion or any other form of assurance with respect thereto. Statement of Comprehensive Loss

43 Statement of Cash Flows Nautilus Biotechnology Confidential – Do Not Distribute Note: Financial data above are unaudited and subject to change based upon completion of a PCAOB audit for the fiscal year ended December 31, 2019. The preliminary financial data included herein has been prepared by, and is the responsibility of Nautilus' management. Nautilus' independent registered public accounting firm has not audited, reviewed, compiled, or applied agreed-upon procedures with respect to the preliminary financial data. Accordingly, Nautilus's independent registered public accounting firm does not express an opinion or any other form of assurance with respect thereto.

Nautilus Biotechnology Confidential – Do Not Distribute 44 Year ending December 31, ($ in millions) 2021 2022 2023 2024 2025 Total Revenue $0 $4 $17 $77 $183 Gross Profit $0 $1 $9 $49 $127 EBITDA(3) ($46) ($72) ($84) ($73) ($42) Nautilus’ Projected Financial Information(1), (2) Notes:(1) The financial projections reflect numerous estimates and assumptions with respect to general business, economic, regulatory, market and financial conditions and other future events, as well as matters specific to Nautilus’ business, all of which are difficult to predict and many of which are beyond Nautilus’ control. The financial projections are forward looking statements that are inherently subject to significant uncertainties. This information should be read in conjunction with the “Summary Risk Factors” included herein.(2) No independent auditor or independent registered public accounting firm or any other independent accountants have compiled, examined or performed any procedures with respect to the financial projections included herein, nor have they expressed any opinion or any other form of assurance on such information or their achievability, and they assume no responsibility for, and disclaim any association with, the financial projections. (3) Earnings before Interest, Taxes, Depreciation, Amortization, and stock-based compensation or EBITDA, is a non-GAAP measure. Management uses non-GAAP measures to compare Nautilus’ performance relative to forecasts and strategic plans and to benchmark Nautilus’ performance. Non-GAAP information is not prepared under a comprehensive set of accounting rules and should only be used to supplement an understanding of Nautilus’ operating results as reported under U.S. GAAP. Nautilus is unable to present a quantitative reconciliation of forward-looking non-GAAP financial measures because management cannot reliably predict all of the necessary components of such GAAP measures. Among other examples, Nautilus cannot reliably predict future stock-based compensation charges or other charges whose determination is dependent on facts and circumstances applicable at the time such charges are determined.

Summary Risk Factors 1 Risks Associated with Nautilus’ BusinessNautilus’ business is subject to numerous risks and uncertainties that you should consider before investing. The summary risks and uncertainties described below are not the only ones Nautilus faces. Additional risks and uncertainties not currently known to Nautilus or that Nautilus currently deem less significant may also affect Nautilus’ business operations or financial results. If any of the following risks actually occur, Nautilus stock price, business, operating results and financial condition could be materially adversely affected. These risks include, but are not limited to, the following: Nautilus is a development-stage company that has incurred net losses in every period to date, that has not yet commercialized any products, and that expects to continue to incur significant losses as it develops its business. Nautilus is entirely dependent on the success of its proteomics product platform, which remains in the development stage and subject to scientific and technical validation. Nautilus has not yet commercially launched its proteomics product platform. Nautilus may not be able to launch its platform successfully and even if it is successful may experience material delays in its commercialization program relative to current expectations.Even if Nautilus is able to complete development of its proteomics product platform, it may not achieve or maintain significant commercial market acceptance.If Nautilus is unable to establish manufacturing capacity by itself or with partners in a timely manner after completing development, commercialization of its proteomics product platform would be delayed, which would result in lost revenue and harm its business.If Nautilus is unable to establish an effective commercial organization, including effective distribution channels and sales and marketing functions, it may not be successful in commercializing its proteomics product platform.The commercialization of Nautilus’ products will require Nautilus to establish relationships with leading life science companies and research institutions, initially to test and validate its products and subsequently as Nautilus seeks to expand the markets for its products. Nautilus may be unable to establish sufficient collaborations of this nature, and collaborations could result in agreements that limit or otherwise impair Nautilus’ flexibility to pursue other strategic opportunities.Nautilus’ operating results may fluctuate significantly in the future, which makes its future operating results difficult to predict and could cause its operating results to fall below expectations or any guidance Nautilus may provide.The life sciences technology market is highly competitive. If Nautilus fails to compete effectively, its business and results of operation will suffer.If Nautilus is unable to obtain and maintain sufficient intellectual property protection for its products and technology, Nautilus’ ability to successfully commercialize its products may be impaired.The COVID-19 pandemic and efforts to reduce its spread have adversely impacted and are expected to continue to materially and adversely impact, Nautilus’ business and operations.If Nautilus fails to maintain an effective system of internal control over financial reporting, it may not be able to accurately report its financial results in a timely manner or prevent fraud, which would harm its business.Nautilus will incur significant increased costs as a result of operating as a public company. Nautilus Biotechnology Confidential – Do Not Distribute