First Quarter 2023 Earnings Presentation May 10, 2023

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The Company believes these non-GAAP measures of financial results provide useful information to management and investors regarding certain financial and business trends relating to the Company’s financial condition and results of operations. The Company’s management uses these non-GAAP measures for trend analyses and for budgeting and planning purposes. A reconciliation of these non-GAAP financial measures to the closest GAAP measure is included in the Appendix to the Presentation. You should review the Company’s audited financial statements prepared in accordance with GAAP, which are included in its Annual Report on Form 10-K filed with the SEC. Forward-looking non-GAAP financial measures are presented without reconciliations to GAAP measures because the GAAP financial measures are not accessible on a forward-looking basis, and reconciling information is not available without unreasonable effort due to the inherent difficulty in forecasting and quantifying certain amounts that are necessary for such reconciliations. For the same reasons, the Company is unable to address the probable significance of the unavailable information, which could be material to future results. TRADEMARKS This Presentation contained trademarks, service marks, trade names, and copyrights of, the Company, and other companies, which are the property of their respective owners. The information contained herein is as of May 10, 2023, and does not reflect any subsequent events. Forward-Looking Statements and Non-GAAP Financial Results 2

FAST FACTS Founded in 2004(went public in 2020) 480 patents & pending patent applications 15 partnerships with major brands and distributors 265 Teammates 2018 and 2020 recipient of PLASTICS Innovation in Bioplastics Award Locations in Georgia, Kentucky, and New York Manufacturer of PHA Biopolymers 3

Certified biodegradable for home compost, natural soil and marine environments Highly-engineered to run on standard manufacturing equipment Indistinguishable from petroleum plastic to consumers at end-use Proprietary PHA-Based Resins with Disruptive Performance 1 Switch to PHA-based resin requires significant customer commitments Creates brand benefits and mitigates risk from future regulatory mandates Funded joint development partnerships lead to commercial launches Adoption of Sustainable Materials is Strategic and Persistent 2 Production rate at or above current target Nameplate capacity of ~32.5 mm LBs of neat PHA, ~65 mm LBs of finished resin At full capacity utilization and current market pricing and mix, expect ~$190 mm revenue and very strong contribution margin Kentucky Plant Capacity Serves Near-Term Demand 3 Solid liquidity position provides runway to positive EBITDA Awaiting approval of Part 2 application for DoE loan to fund Greenfield facility Intellectual property contribution drives favorable partnership economics for stand-up of catalytic PHA production. Stronger capacity utilization to drive contribution margin at Kentucky plant Bainbridge greenfield plant design more efficient; drives scale benefits with ~$400mm of new capacity Expect catalytic technology (DCT) to be a high-margin path to new markets, additional scale, and licensing opportunities Deeply capable executive team with cadre of veterans and strong new leaders Talented engineering, research & development, and technical sales teams Driven culture with deep commitment to helping solve global environmental and pollution issues Short, Medium & Long-Term Strategic Finance Initiatives Ongoing Opportunity for Margin Expansion World-Class Teams and a Powerful Culture 4 5 6 Key Investment Highlights 4

Kentucky Manufacturing – Process & Capability ¹ Intended to illustrate maximum potential at full utilization of design capacity; assumes pricing of $3 per lb. ~32.5 mm LBS of Neat PHA = ~65 mm LBS Formulated PHA-Based Resin = ~$190 mm Revenue¹ 5

Began multi-store test of Nodax®-based straws with prominent QSR chain in preparation for wider roll-out in 2H23 In final discussions with customer requiring significant annual volumes of Nodax®-based straw resin, with first shipments expected in 2H23 In advanced negotiations with new customer requiring significant annual volume of Nodax®-based cutlery resin, with first shipments expected in 1Q24 Wincup extended Phade® product line to include cups with Nodax®-based coating material Completed development, in partnership with TotalEnergies Corbion, of Nodax®-based resin for single-use coffee pods, received TUV Austria certification (meeting proposed EU requirements for biodegradability) for “Home Compost” -- in testing with multiple potential new customers Reinforcing continuous improvement focus in process engineering at Kentucky manufacturing facility to benefit product quality, efficiency and margins Capture of ongoing benefit related to broad cost control initiative – $4.7 million YoY improvement in adjusted operating and R&D expenses Recent Customer & Business Development Highlights 6

Q1 2023 Financial Summary Lower sales versus 1Q22 reflects a $2.1 million of net lower product shipments due to customer timing of PHA-based resins, partially offset by modest growth in PLA-based resin sales as well as $0.7 million of lower funded R&D revenue as customers move to commercialization. Adjusted Gross Profit primarily reflects the impact of lower revenues and increased fixed costs associated with additional capacity in Kentucky. Lower R&D and SG&A spending reflects successful cost control initiatives across many areas of the business. Q1 Comments Financial Summary 7

1Q23 results in-line with expectations. Increased visibility and confidence in specific customer requirements. No adjustments to prior guidance. Customer timing adjustment now complete, expect return to quarterly YoY growth in 2Q23. Continue to expect acceleration of YoY revenue growth rates through 2H23. 7 Guidance Summary

Appendix

EBITDA Reconciliation 9

Adjusted Gross Profit Reconciliation 10

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