Slide 1: Support Long-Term Value Creation at Seer
Support Long-Term Value Creation at Seer
Slide 2: Safe harbor disclosures: Forward Looking Statements
Safe harbor disclosures Forward Looking Statements The forward-looking statements in this presentation are made only as of the date hereof. For a further Certain statements in this presentation and the accompanying oral commentary are forward-looking description of the risks and uncertainties that c
Slide 3: Table of contents
Table of contents I. Executive Summary 4 II. What This Contest Really is About 9 III. What Radoff-JEC’s Offer Would Permanently Destroy 15 IV. The Board Has Delivered and the Inflection Point is Close 28 V. An Independent, Accountable Board with the Right Expertise 40 VI. A Forced Sale Campaign Dres
Slide 4: Executive Summary
Executive Summary © 2026 Seer, Inc. 4
Slide 5: What is This Proxy Contest About?
What is This Proxy Contest About? • This proxy contest is not about whether the stock has performed. It is about whether Radoff-JEC will be permitted to install nominees whose sole purpose is to sell Seer before we have reached our full potential • Seer’s Board is independent, qualified, and highly
Slide 6: Seer at a glance
Seer at a glance Seer imagines and pioneers new ways to unlock the power of the proteome to improve human health We enable novel biological insight through deep, unbiased, reproducible and accurate proteomic data at scale • Seer is a pioneer in deep, unbiased proteomics at scale using proprietary en
Slide 7: The Board has delivered cost discipline and product innovation
The Board has delivered cost discipline and product innovation Cost discipline, governance rigor, and significant new product introductions all during a sector downturn Our Board has protected Stockholder interests Our Board & Governance are purpose-built 1 ✓ We have reduced annual cash burn by 36%
Slide 8: Three nominees, one purpose: Sell Seer early
Three nominees, one purpose: Sell Seer early Radoff-JEC’s three nominees lack the proteomics, instrumentation, and operating experience Seer requires at its commercial inflection point Joshua S. Horowitz Luis E. Rinaldini Howard H. Berman, Ph.D. × Small-cap generalist investor, not a sector × A care
Slide 9: What This Contest Really is About
What This Contest Really is About Change is Not Warranted © 2026 Seer, Inc. 9
Slide 10: Repeated attempts to undervalue Seer and take our cash
Repeated attempts to undervalue Seer and take our cash The Radoff-JEC’s only desire is to strip the Company of its cash “To be clear, the acquisition proposals could be financed with the cash on the Company’s balance sheet.” 1 × Radoff-JEC’s own definitive proxy filing confirms that their nominees t
Slide 11: Engagement timeline
Engagement timeline Board engaged in good faith – Radoff-JEC escalated toward a forced sale Radoff-JEC emerges Protecting our NOLs Smear and slander February 20, 2026 February 26, 2026 March 12, 2026 Radoff-JEC publicly disclosed their Board adopted the Tax Benefit Preservation Plan Radoff-JEC priva
Slide 12: Engagement timeline (cont'd)
Engagement timeline (cont’d) Board engaged in good faith – Radoff-JEC escalated toward a forced sale Unanimous rejection Escalation and more accusations The Contest Goes Definitive April 27, 2026 May 27, 2026 June 3, 2026 The Board unanimously rejected Radoff- Radoff-JEC published a third open lette
Slide 13: Three bids: Each carefully reviewed and rejected by our Board
Three bids: Each carefully reviewed and rejected by our Board Radoff-JEC’s bids are an attempt to strip our cash 4/13/26 Proposal 4/24/26 Proposal 5/14/26 Proposal Misaligned incentives Radoff-JEC’s offers are intended to strip the Company of its cash – Radoff-JEC is attempting to buy Seer at a disc
Slide 14: We've adopted what works and rejected what destroys value
We’ve adopted what works and rejected what destroys value Radoff-JEC’s demands fall into three categories: already pursued, superficial, or value-destroying Rationale Activist Demand Reducing costs within headcount and non-personnel expenses in order to extend cash runway without compromising Cost r
Slide 15: What Radoff-JEC's Offer Would Permanently Destroy
What Radoff-JEC’s Offer Would Permanently Destroy Introduction to Seer © 2026 Seer, Inc. 15
Slide 16: Seer powers AI-driven precision medicine with proteomic data
Seer powers AI-driven precision medicine with unbiased, deep, and scalable proteomic data The market inflection is happening now and Radoff-JEC's plan would deprive Seer stockholders of the upside Biological discovery is at an inflection point and proteomic content will Seer is uniquely positioned t
Slide 17: Proteomics is critical to enabling precision medicine
Proteomics is critical to enabling precision medicine Understanding the proteome represents a paradigm shift in life sciences, which Radoff-JEC's offer would fail to realize Genomics Proteomics “Genomics is not fully compatible Only a small percentage of drugs target genes Most drug targets are prot
Slide 18: Targeted and unbiased proteomics have distinct utility
Targeted and unbiased proteomics have distinct utility Discovery of new protein variants is uniquely possible with unbiased proteomics, which enables existing end market expansion and new end market creation Affinity-Based Approaches Low Correlation for the Same Protein (0.38) “Protein–phenotype col
Slide 19: Seer enables deeper proteomic insights
Seer enables deeper proteomic insights 1 Seer has a measurable and defensible lead built over 8 years that Radoff-JEC wants to capture for $2.40 + CVR Data Points per Sample Significantly more data to train foundation models and reveal deeper insights ~11 measurements per protein >77,000 More data p
Slide 20: Seer can annotate the reliability of pQTL findings
Seer can annotate the reliability of pQTL findings of affinity-base technologies True pQTL identification High-significance pQTLs in UKB & deCODE scored according to evidence in a Seer-analyzed cohort rd 1/3 of pQTLs show high evidence in Seer data, rd 1/3 low evidence; pQTLs found by both Olink and
Slide 21: Population-scale, deep, unbiased proteomics studies drive novel insight
Population-scale, deep, unbiased proteomics studies drive novel biological insight We anticipate that biobanks will be lighthouse customers that will drive additional business • 20,000 samples in total • 10,000 samples across ~50 different • Completed 10,000 samples; data • $50M multi-institutional
Slide 22: Breaking bottlenecks with an end-to-end solution
Breaking bottlenecks with an end-to-end solution Bottlenecks Instrument Assay Sample Preparation + Depth 2025 SP200 2021 RISe 2023 XT 2025 ONE 2027 Proteoform Profiling Assay Detector Designed for bottom-up discovery proteomics, delivering unparalleled throughput and robustness without Robustness co
Slide 23: Protein Analyzer will open up a new end market for non-MS users
Protein Analyzer will open up a new end market for non-MS users Why Seer can expand proteomics beyond expert mass spec users Protein Analyzer • High-volume proteomics researchers Target • Biopharma, CROs, and core lab segments Fit-for-purpose system with compelling performance and usability Customer
Slide 24: Protein Analyzer unlocks Next Generation Proteomics
Protein Analyzer unlocks Next Generation Proteomics and will vastly expand the proteomics market Next generation proteomics (NGP) requires all of: Proteomics Market Expansion • Standardized workflow • Depth of content • Scalability 1 • Ease of use Existing LC-MS and panel (affinity-based) proteomics
Slide 25: Seer changed the arc of proteomics
Seer changed the arc of proteomics 2027 Early-access Protein Analyzer release and very Deep Unbiased large-scale studies scale to 100K+ samples Study Size (# samples) 2026 Korea University results presented at ASMS, PRECISE study results to be shared at iHUPO 2025 Launch Proteograph ONE to do studie
Slide 26: Seer's asset base spans a core operating business
Seer’s asset base spans a core operating business Proteograph: Platform PrognomiQ Proteograph: Software Protein Analyzer Balance sheet and Assay Minority ownership in a Asset Workflow, data and Next-generation detector in Cash and financial Core commercial separately capitalized analysis layer devel
Slide 27: Seer is pioneering a new market
Seer is pioneering a new market The Radoff-JEC plan would sacrifice a $23B market opportunity for a short-term exit Substantial and Fast-Growing Market Opportunity Trends and Key Drivers of Market Growth Proteomics Total Addressable Market ~50,000 mass spectrometry instruments installed globally, gr
Slide 28: The Board Has Delivered and the Inflection Point is Close
The Board Has Delivered and the Inflection Point is Close Strategy and Performance © 2026 Seer, Inc. 28
Slide 29: Seer is executing on its IPO commitments
Seer is executing on its IPO commitments Seer’s goals at IPO Demonstrable progress “Sales of new products into new market opportunities may take years to develop and mature and we cannot be certain that these market opportunities will develop as we “There are now 84 peer-reviewed publications, prepr
Slide 30: Meaningful SG&A and R&D reductions from 2023 peak
Prudent Board and Management decisions have led to meaningful SG&A and R&D reductions from 2023 peak ($ in millions) Gross Profit SG&A R&D $53 52% 51% 51% $51 $59 $59 50% $57 46% $46 $44 $46 $43 $29 2021 2022 2023 2024 2025 2021 2022 2023 2024 2025 2021 2022 2023 2024 2025 Source: Company Filings ©
Slide 31: Disciplined equity grants over time
Disciplined equity grants over time ($ in millions) Stock-based Compensation Our Approach to Equity Grants Has Been Measured • Reduced stock-based compensation by ~75% since 2022, reflecting a disciplined, stockholder-aligned approach to equity $34.4 $33.7 • Rather than issuing new equity at depress
Slide 32: Cash burn has fallen every year since 2022
Cash burn has fallen every year since 2022 – while we build our platform We have invested significantly in standing up our platform and will reap the benefits in years to come $71M $66M $49M $46M 2022 2023 2024 2025 ✓ Broad commercial release of Proteograph ✓ Proteograph XT assay launched✓ SIPP and
Slide 33: Installed base is compounding
Installed base is compounding 62% CAGR in installed instruments and partnerships with every major platform Cumulative growth in installed base Partnership announcements Nov’24: co-marketing alliance pairing Proteograph with Orbitrap Astral – first joint 82 sales closed 3Q25 Jan’22: multi-year collab
Slide 34: TSR has lagged, but we are at an inflection point
TSR has lagged, but we are at an inflection point ($ in millions) Drivers of future value Drivers of underperformance Early-stage commercialization phase Expanding installed base brings recurring consumables revenue High upfront R&D and infrastructure investment New product introductions create high
Slide 35: Market development to broad scale adoption
Protein Cumulative Cumulative customer 1 customers publications studies Market development to broad scale adoption 2026 Q1 >17,000 2025 >13,000 2024 205 2023 >13,000 2022 195 2021 >8,000 First population- Pre-Proteograph >6,000 scale studies 121 >3,000 initiated 53 84 Not possible 19 to do deep 8 70
Slide 36: Diversified and expanding customer base
Diversified and expanding customer base These relationships have taken years to build and we are beginning to realize the value from them Academic & translational research Commercial footprint Early access Early access Center of partner partner Excellence 8 Centers of Excellence globally Center of K
Slide 37: Building the future of unbiased proteomics
Building the future of unbiased proteomics Executing against a clear roadmap to deliver market leadership, financial strength, and transformative impact 12+ MONTHS 24+ MONTHS 24 – 36 MONTHS 36 – 48 MONTHS Protein Analyzer Acceleration of revenue Cash flow positive with At scale market leader for par
Slide 38: From category creation to commercial scale
From category creation to commercial scale Seer pioneered protein enrichment solutions, earned industry validation, and is ready to scale 2017 – 2020 2020 and beyond Today Invent Validate Scale Create the deep, unbiased protein Growing customer publications, initiation of Category leadership enables
Slide 39: A strong track record of innovation with a robust product pipeline
A strong track record of innovation with a robust product pipeline ahead 2021 2022 2023 2024 2025 2026 2027+ Instrument Instrument Instrument SP100 Launch SP200 Launch Protein Analyzer Assay Assay Assay Assay RiSE XT ONE Proteoform Profiling Assay Kit Software Software Software Software PAS 2.0 PAS
Slide 40: An Independent, Accountable Board with the Right Expertise
An Independent, Accountable Board with the Right Expertise Corporate Governance © 2026 Seer, Inc. 40
Slide 41: Strong and relevant CEO track record
Strong and relevant CEO track record Dr. Farokhzad has a 20-year track record of building platform companies in drug delivery and cell therapy 14-year tenure building a clinical-stage platform Founded and chaired through Series D and a Took a novel delivery platform from co-founding Brought Senti pu
Slide 42: An independent Board with the right expertise
An independent Board with the right expertise – refreshed and accountable 5.5 Years Avg Tenure 100% Prior Healthcare Experience A Majority of Our Directors Have Financial Backgrounds 5 of 7 Directors are Independent 2 Directors Added In The Last 2 Annual General Meetings Lead Independent Director Al
Slide 43: Board of Directors' qualifications
Board of Directors’ qualifications Chair Member Focused experience Committee membership Board Member Tenure Age Independent Industry Life science Public Company Science & Talent & Governance & Financial Audit (Healthcare) tools C-Suite Technology Compensation Nominating Omid Farokhzad, M.D. 9 years
Slide 44: Corporate governance aligned with best practice
Corporate governance aligned with best practice Our corporate governance practices ensure stockholders are represented in the boardroom Tax benefit preservation plan 1 • Seer has $262.4M of federal NOLs Annually elected directors • Adopted to protect Seer’s valuable net operating loss carryforwards
Slide 45: PrognomiQ spinout reflects sound governance and capital allocation
PrognomiQ spinout reflects sound governance and disciplined capital allocation 1 PrognomiQ spinoff Dependence on PrognomiQ revenue has declined % of total Strategically sound separation: In 2020, Seer spun out PrognomiQ as a dedicated clinical 34% 28% 16% 5% Rev diagnostics company — keeping Seer's
Slide 46: Governance criticisms fall flat under scrutiny
Governance criticisms fall flat under scrutiny Radoff-JEC has criticized our combined Chair / CEO • Mr. Nicolas Roelofs, in his role as Lead Independent Director, presides over periodic meetings of our independent directors and serves as a Our Lead Independent Director, Nicolas Roelofs, has liaison
Slide 47: Governance criticisms fall flat under scrutiny (cont'd)
Governance criticisms fall flat under scrutiny (cont’d) Radoff-JEC has criticized our compensation decision behind option repricing • We responsibly structured our repricing at $2.00, the closing market price on the repricing date, with an 18-month retention for the repricing to take 1 effect to ens
Slide 48: Governance criticisms fall flat under scrutiny (cont'd)
Governance criticisms fall flat under scrutiny (cont’d) Radoff-JEC has criticized our director attrition, founder-network overlap, and relationship to PrognomiQ • The current Board’s tenures range from 1 to 9 years, with an average of ~5.5 years In line with corporate governance best practices, Seer
Slide 49: A Forced Sale Campaign Dressed Up as Governance Reform
A Forced Sale Campaign Dressed Up as Governance Reform The Radoff-JEC Campaign © 2026 Seer, Inc. 49
Slide 50: Radoff-JEC's comparisons don't survive scrutiny
Radoff-JEC’s comparisons don’t survive scrutiny Radoff-JEC’s statements Seer’s response • Radoff-JEC’s preliminary proxy compares us to the S&P Biotechnology Select Industry Index when we are not a biotech company. This illustrates Radoff-JEC’s lack of knowledge of our business • The sector has been
Slide 51: Radoff-JEC's comparisons don't survive scrutiny (cont'd)
Radoff-JEC’s comparisons don’t survive scrutiny (cont’d) Radoff-JEC’s statements Seer’s response • Markets are forward-looking; we have been transparent with the market about our Shares trade at a discount to net cash; market assigns negative value to path to breakeven as we scale this new technolog
Slide 52: Radoff-JEC's comparisons don't survive scrutiny (cont'd)
Radoff-JEC’s comparisons don’t survive scrutiny (cont’d) Radoff-JEC’s statements Seer’s response • Executive pay is set by an all-independent committee advised by Aon as independent compensation consultant — with Dr. Omid Farokhzad absent from all The Board has enriched the CEO at $24.9M total comp
Slide 53: Radoff-JEC's comparisons don't survive scrutiny (cont'd)
Radoff-JEC’s comparisons don’t survive scrutiny (cont’d) Radoff-JEC’s statements Seer’s response • PrognomiQ was spun out specifically to avoid this conflict There are independence conflicts with PrognomiQ and dependence on revenue • Seer retained only a minority stake consistent with responsible sp
Slide 54: The Wrong People at the Wrong Time for the Wrong Reasons
The Wrong People at the Wrong Time for the Wrong Reasons Their Nominees Are the Wrong Answer © 2026 Seer, Inc. 54
Slide 55: Three nominees, one purpose: Sell Seer early
Three nominees, one purpose: Sell Seer early No proteomics, no life sciences instrumentation, no operating experience Joshua S. Horowitz Luis E. Rinaldini Howard H. Berman, Ph.D. Portfolio manager at Palm Management (US) running a multi-sector small-cap Founder of Groton Partners; former Vice Chairm
Slide 56: Our Directors' experience is critical going forward
Our Directors’ experience is critical going forward Our Nominees bring the best combination of industry experience, capital allocation, and long-term stewardship Dr. Omid Farokhzad Terry McGuire Deep Nishar Co-founder, Chairman & CEO of Seer; the scientific and architect of Seer's Founding Partner o
Slide 57: The Case For Voting BLUE
The Case For Voting BLUE Key Takeaways and Ask © 2026 Seer, Inc. 57
Slide 58: Key takeaways
Key takeaways Is change warranted? Are Radoff-JEC nominees right for Seer? No No The sector has been down. Peers have followed. The Board Three nominees with no ownership of Seer shares between responded with cost discipline: cash burn down 36%, OpEx them, no scientific background, no commercial pla
Slide 59: Please vote the BLUE card FOR Seer's Director nominees
Please vote the BLUE card FOR Seer’s Director nominees We strongly urge stockholders to vote the BLUE proxy card for our highly qualified and experienced nominees to support the continued execution of our Seer strategy Company nominees: Radoff-JEC nominees opposed by the Company: The Board of Direct
Slide 60: Appendix
Appendix © 2026 Seer, Inc. 60
Slide 61: Overview of Board of Directors
Overview of Board of Directors Omid Farokhzad, M.D. Meeta Gulyani Founder, Chair & CEO SVP and General Manager, Bioprocessing & Head of Life Science Strategy, Ecolab • Founder of Seer — the scientific architect behind the Proteograph and the Company's • Chair of the Audit Committee; member of Seer’s
Slide 62: Overview of Board of Directors (cont'd)
Overview of Board of Directors (cont’d) Robert Langer, Sc.D Terry McGuire Co-Chairman, Scientific Advisory Board Founding Partner, Polaris Partners • Chair of the Science and Technology Committee; member of Seer’s Board since 2017; • Chair of the Talent and Compensation Committee; member of Seer’s B
Slide 63: Overview of Board of Directors (cont'd)
Overview of Board of Directors (cont’d) Deep Nishar Isaac Ro Former Managing Director, General Catalyst Partner, Catalio Capital Management • Member of Seer’s Board since 2021 • Member of Seer’s Board since 2025 • Currently also serves on the Board of Gladstone Institutes • Partner at Catalio Capita
Slide 64: Overview of Board of Directors (cont'd)
Overview of Board of Directors (cont’d) Nicolas Roelofs, Ph.D. Former President of the Life Sciences Group at Agilent Technologies • Lead Independent Director; member of Seer’s Board since 2024 • Currently also serves on the Board of LGC Group • Previously served on the Boards of several public and
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