June 2024 A Diversified Holding Company with Two Divisions Building Solutions Division Investments Division Real Estate Private Investments Public Investments • Star Equity Fund is a portfolio of public equities managed by STRR. • Makes strategic investments in undervalued public companies, and potential acquisition targets or JV partners. • Owns, manages, and finances operating company real estate assets. • Negotiates standalone financing to optimize financial leverage and cost of capital. Colfax, WI • Designs and manufactures engineered wood products: glue-laminated timber (“glulam”) columns, beams, and trusses. Minneapolis-St Paul Area • Designs and manufactures wood wall panels and permanent wood foundations. • Distributes building materials and operates two lumber yards and showrooms. South Paris, ME • Designs and manufactures modular structures for commercial and residential projects. • Holds private company debt and minority equity interests. • Makes strategic investments in potential acquisition targets or JV partners. Recently added Big Lake Lumber Recently added (1) 5/31/24 closing price. (2) 5/15/24 share count. Common Stock (Nasdaq: STRR): Stock Price (1): $0.86 15.8 million shares outstanding (2) Series A Preferred Stock (Nasdaq: STRRP): Stock Price (1): $9.41 1.92 million shares outstanding (2) 10% annual cash dividend (1) 5/31/24 closing price. (2) 5/15/24 share count. KBSEBGL TT Big Lake, Minnesota Lumber Yard - 20,000 sq ft South Paris, Maine KBS - 85,000 sq ft Oxford, Maine Idle - 90,000 sq ft Colfax, Wisconsin TT - 69,000 sq ft 3 Facilities with a total value of $7.5M (1) Real Estate Portfolio Purchase of 4th facility expected to close in June (2) Differentiated Corporate Strategy and Structure (1) Public activism efforts are not always in pursuit of acquisition. Looking for accretive bolt-ons and new verticals Flexible deal structuring given ability to use mix of cash, debt, common, preferred Long-term partnership approach rather than short-term transactional mentality Star Equity shareholders do not pay any fees and have public market liquidity Open-ended investment time horizon allows for flexible holding periods Operating Businesses Real Estate / Factories Showrooms Private Investments Company HQ Public Investments (1) See STRR’s June 2024 deck - slide 27 for further detail. (2) Purchase agreement in place; expected to close June 2024. Able to pursue both private and public acquisition targets, sometimes through activism (1) Consolidated Financial Highlights Scaling and optimizing operations to achieve sustained profitability Growth Strategy Using a multi-pronged approach ✓ Create value across portfolio of public and private investments ✓ Pursue sale-leaseback and other financings to unlock latent value in real estate portfolio Investments Division ✓ Local operating management teams freed up to maximize operations and pursue growth opportunities due to Star corporate staff handling corporate functions ✓ Improve access to capital and lower the cost of capital ✓ Support bolt-on acquisition diligence and execution ✓ Improve operating and financial performance ✓ Achieve cost synergies through reducing SG&A and/or public company costs – Share certain corporate functions to reduce corporate overhead Acquisition Objectives ✓ Businesses with growth potential and strong local operating management teams ✓ Existing assets and earnings (no start-ups or venture capital-type situations) ✓ Expected target size of $5-50M – Businesses that are more valuable inside our holding company structure ✓ Bolt-ons for existing platform businesses or new verticals for Star – Acquisitions can establish new divisions Acquisition Criteria (1) $14.7M Cash $20.3MInvestments$1.9MDebt (1) Excludes discontinued operations; (2) Pro forma financials as reported on May 10, 2023 8-K; (3) Adjusted EBITDA is a non-GAAP measure - refer to the Investor Presentation filed with the SEC for a reconciliation to net income. (4) Refer to the Investor Presentation filed with the SEC for more information. Recent Acquisition: Timber Technologies $7.5M Real Estate(4) ✓ Increase KBS’s manufacturing capacity & output by expanding South Paris, ME plant ✓ Explore opportunities to re-open Oxford, ME plant ✓ Expand presence in each of KBS and EBGL’s markets by increasing output and adding new products and services Long-term goals: ✓ KBS: mid-teens annual rev. growth ✓ EBGL: high single-digit annual rev. growth ✓ TT: high single-digit annual rev. growth Building Solutions Division Added significant scale, more than doubling Building Solutions Net Income & Adj. EBITDA Star Building Solutions Segment Timber Technologies (4) Unaudited; (5) Adjusted EBITDA is a non-GAAP number. Refer to the Investor Presentation filed with the SEC for a reconciliation to net income. M&A - Seeking attractive acquisition opportunities to: ✓ Expand existing business divisions through bolt-on acquisitions ✓ Establish new business divisions $45.8 $18.8 $- $20.0 $40.0 $60.0 FY 2023 Total Revenue (in millions) (4) $2.5 $5.3 $- $2.0 $4.0 $6.0 FY 2023 Net Income (in millions) (4) $4.4 $5.5 $- $2.0 $4.0 $6.0 FY 2023 Adjusted EBITDA (in millions) (5) ($15.4) ($5.8) ($1.9) ($16.0) ($12.0) ($8.0) ($4.0) $0.0 FY 2021 FY 2022 FY 2023 Net Income ($ in millions) $48.0 $57.1 $45.8 $- $20.0 $40.0 $60.0 FY 2021 FY 2022 FY 2023 Revenue ($ in millions) (2) (2) 5.8% 21.6% 26.0% 0% 10% 20% 30% FY 2021 FY 2022 FY 2023 Gross Margin (%) (2) (2) $6.8 $5.4 ($0.1) ($0.2)($1.0) $1.0 $3.0 $5.0 $7.0 FY 2022 FY 2023 Adj. EBITDA ($ in millions) Operating Business EBITDA Adj. EBITDA Corp. Costs ($6.9) Corp. Costs ($5.6) (CAGR 2019 - 2023 = 17.2%) (CAGR 2019 - 2023 = 5.6%) Division-wide: 10%+ annual rev. growth with gross margins above 25% (3)