X0609 4 2026-04-21 0002009684 Seaport Entertainment Group Inc. SEG 0001336528 Pershing Square Capital Management, L.P. false 787 ELEVENTH AVENUE 9TH FLOOR NEW YORK NY 10019 true true 0002026053 PERSHING SQUARE HOLDCO, L.P. false 787 ELEVENTH AVENUE 9TH FLOOR NEW YORK NY 10019 true true 0002027508 Pershing Square Holdco GP, LLC false 787 ELEVENTH AVENUE 9TH FLOOR NEW YORK NY 10019 true true 0002027456 Pershing Square Management, LLC false 787 ELEVENTH AVENUE 9TH FLOOR NEW YORK NY 10019 true true 0001056513 ACKMAN WILLIAM A false 787 ELEVENTH AVENUE 9TH FLOOR NEW YORK NY 10019 true true false Common Stock, par value $0.01 per share 2026-04-21 4 J 0 90875 22.25 D 4932905 I See Footnotes Common Stock, par value $0.01 per share 2026-04-21 4 J 0 90875 22.25 A 90875 I See Footnotes Reflects a transfer of the Subject Securities (as defined below) from PSLP (as defined below) to PS Redemption, L.P. ("RedemptionCo"), which was formed for the purpose of giving effect to the special redemption of certain limited partner interests of PSLP in connection with a special redemption opportunity that was consummated on April 21, 2026. The closing price of the Issuer's Common Stock on April 21, 2026. In addition to Pershing Square Capital Management, L.P., a Delaware limited partnership ("PSCM"), this Form 4 is being filed jointly by Pershing Square Holdco, L.P., a Delaware limited partnership ("PS Holdco"), Pershing Square Holdco GP, LLC, a Delaware limited liability company ("PS Holdco GP"), Pershing Square Management, LLC, a Delaware limited liability company ("ManagementCo"), and William A. Ackman, a citizen of the United States of America (collectively, the "Reporting Persons"), each of whom has the same business address as PSCM and may be deemed to beneficially own the securities reported on this Form 4 (the "Subject Securities"). PSCM advises the accounts of Pershing Square, L.P., a Delaware limited partnership ("PSLP"), Pershing Square International, Ltd., a Cayman Islands exempted company ("PSI"), and Pershing Square Holdings, Ltd., a limited liability company incorporated in Guernsey ("PSH" and together with PSLP and PSI, the "Pershing Square Affiliated Funds") and RedemptionCo. (A) PSCM, as the investment adviser to the Pershing Square Affiliated Funds and RedemptionCo, (B) PS Holdco, as the indirect 100% holding company of PSCM, (C) PS Holdco GP, as the sole general partner of PS Holdco and (D) ManagementCo, as the sole member of PS Holdco GP, may each be deemed to be the beneficial owner of the Subject Securities for purposes of Rule 16a-1(a) under the Securities Exchange Act of 1934 (the "Exchange Act"). By virtue of Mr. Ackman's position as (i) the Chief Executive Officer of PSCM, (ii) a director of PS Holdco GP and (iii) a member of ManagementCo, Mr. Ackman may be deemed to be the beneficial owner of the Subject Securities for purposes of Rule 16a-1(a) under the Exchange Act. Each of the Reporting Persons disclaims any beneficial ownership of any of the Subject Securities, except to the extent of any pecuniary interest therein. Anthony F. Massaro, a member of the board of directors of the Issuer of the Subject Securities, was appointed to that board as a representative of PSCM, the other Reporting Persons and the Pershing Square Affiliated Funds. As a result, each of those persons are directors by deputization for purposes of Section 16 of the Exchange Act. These Subject Securities are held by the Pershing Square Affiliated Funds. These Subject Securities are held by RedemptionCo. PERSHING SQUARE CAPITAL MANAGEMENT, L.P., By: /s/ William A. Ackman, Authorized Signatory 2026-04-23 PERSHING SQUARE HOLDCO, L.P., By: Pershing Square Holdco GP, LLC, its General Partner, By: /s/ William A. Ackman, Authorized Signatory 2026-04-23 PERSHING SQUARE HOLDCO GP, LLC, By: /s/ William A. Ackman, Authorized Signatory 2026-04-23 PERSHING SQUARE MANAGEMENT, LLC, By: /s/ William A. Ackman, Member and Chief Executive Officer 2026-04-23 /s/ William A. Ackman 2026-04-23