ISQ Open Infrastructure Company LLC (the “Company”) is a limited liability company that was formed in accordance with the laws of Delaware on January 15, 2025. The Company is a series limited liability company with series established pursuant to Sections 18-215 or 18-218 of the Delaware Limited Liability Company Act (the “LLC Act”). On March 13, 2025, the Company established two registered series of limited liability company interests, ISQ Open Infrastructure Company LLC - Series I (“Series I”) and ISQ Open Infrastructure Company LLC - Series II (“Series II” and together with Series I, “Series”). The purchase of shares of a Series of the Company is an investment only in that particular Series and not an investment in the Company as a whole. In accordance with the LLC Act, each Series is a separate series of segregated assets and liabilities and corresponding limited liability company interests of the Company.

Series I and Series II are intended to be treated as separate entities for U.S. federal income tax purposes with segregated assets and liabilities. Sections 18-215(c) and 18-218(c)(1) of the LLC Act provide that a Series established in accordance with Section 18-215(b) or 18-218 of the LLC Act, respectively, may carry on any lawful business, purpose or activity, other than the business of banking, and has the power and capacity to, in its own name, contract, hold title to assets (including real, personal and intangible property), grant liens and security interests, and sue and be sued. The Company intends for each Series to conduct its business and enter into contracts in its own name to the extent such activities are undertaken with respect to a particular Series and assets associated with a Series may be held, directly or indirectly, including in the name of such Series, in the name of the Company, through a nominee or otherwise. Under Delaware law, to the extent the records maintained for a Series account for the assets associated with such Series separately from the other assets of the Company or any other Series, the debts, liabilities, obligations and expenses incurred, contracted for or otherwise existing with respect to such Series are segregated and enforceable only against the assets of such Series and not against the assets of the Company generally or any other Series.

Each of Series I and Series II will remain in existence until its certificate of registered series has been cancelled in the manner required by the LLC Act following Series I’s or Series II’s, as applicable, dissolution and the completion of the winding up of such Series in accordance with the Fourth Amended and Restated Limited Liability Company Agreement of the Company (the “LLC Agreement”), the applicable series agreement and Delaware law. On August 11, 2026, the LLC Agreement was amended and restated. See “—Subsequent Events” for additional information.

The Company conducts its operations so that neither Series I nor Series II is required to register as an “investment company” under the Investment Company Act of 1940, as amended (the “Investment Company Act”). The Company primarily seeks to manage joint ventures that own and control private companies, infrastructure assets and infrastructure-related assets located globally but with a focus on North America, Europe and selected growth economies in Asia and Latin America (the “Infrastructure Assets”) with the objective of generating attractive risk-adjusted returns consisting of both current income and long-term capital appreciation.

The Company is conducting a continuous private offering of the shares to (i) accredited investors (as defined in Regulation D under the U.S. Securities Act of 1933 (the “Securities Act”)) and (ii) in the case of shares sold outside the United States, to persons that are not “U.S. persons” (as defined in Regulation S under the Securities Act) in reliance on exemptions from the registration requirements of the Securities Act, including under Regulation D and Regulation S.

The Company is sponsored by I Squared Capital Advisors (US) LLC (together with its subsidiaries and affiliated entities, “I Squared”) and benefits from I Squared’s infrastructure sourcing and portfolio management platform pursuant to a management agreement (the “Management Agreement”), entered into with ISQ OpenInfra Registered Advisor LLC (the “Manager”), an affiliate of I Squared, on September 2, 2025, to support the Company in managing its portfolio of Infrastructure Assets. On August 11, 2026, the Company entered into the Amended and Restated Management Agreement with the Manager. See “—Subsequent Events” for additional information.

In pursuing its investment objective, Series I invests substantially all of its assets in Series II. The portfolio of Series I typically consists solely of Series II shares. Therefore, Series I’s investment results correspond directly to the investment results of Series II. Series II has the same business objective and strategy as Series I. For convenience of the reader, references to Series II’s investments also refer to Series I’s investments (and vice versa), and references to the risks of investing in Series II also refer to the risks of investing in Series I (and vice versa), except as otherwise provided. Series I and Series II are part of a master-feeder fund structure. The feeder fund, Series I, invests substantially all of its assets in the master fund, Series II, through the Blocker (as defined below).

On March 28, 2025 (the “Funding Date”), I Squared contributed $2,000 to Series I. Series I contributed $1,000 to Series II through a blocker, ISQ Open Infrastructure Holdings, L.P. (the “Blocker”), domiciled in the Cayman Islands and Series I and Series II commenced operations. The Blocker is wholly-owned by Series I and has therefore been consolidated. I Squared’s initial contribution to Series I was subsequently converted into Class E_TE shares on September 30, 2025.