United States Court of Appeals For the Seventh Circuit ____________________ No. 23-1489 WEC 98C-3 LLC, Plaintiff, and 4 STRATFORD SQUARE MALL HOLDINGS, LLC, Plaintiff-Intervenor-Appellee,

v. SFA HOLDINGS INC., formerly known as SAKS INC., Defendant-Appellant. ____________________

Appeal from the United States District Court for the Northern District of Illinois, Eastern Division. No. 1:20-cv-04356 — Harry D. Leinenweber, Judge. ____________________

ARGUED DECEMBER 7, 2023 — DECIDED APRIL 24, 2024 ____________________

Before WOOD, KIRSCH, and JACKSON-AKIWUMI, Circuit Judges. 2 No. 23-1489

JACKSON-AKIWUMI, Circuit Judge. This case involves two contracts, three litigants, four companies, and millions of dol- lars of unpaid rent. CPS Partnership operated a department store at an Illinois mall for over thirty years. The corporate entities changed over those years but suffice it to say that CPS leased the retail space from a company called WEC 98C-3 LLC, and Saks 1 guaranteed that it would pay the rent if CPS could not. But when CPS stopped paying rent, Saks did not send WEC a single payment. The lost income caused WEC to default on its mortgage, and 4 Stratford Square Mall Hold- ings, LLC (“Stratford”), the successor in interest to WEC’s mortgagee, purchased the property at the foreclosure auction. Initially, WEC sued Saks for damages. Later, Stratford inter- vened with its own distinct claim for damages. The district court ruled only on Stratford’s claim for unpaid rent, finding that it was entitled to payment from Saks. Stratford then waived its claim for non-basic rent damages, and the district court certified the judgment in favor of Stratford for immedi- ate appeal pursuant to Federal Rule of Civil Procedure 54(b). Saks took up the invitation and urges us to reverse. On the jurisdictional grounds for reversal that Saks raises, we con- clude that Stratford did have standing to sue Saks even though it entered the story much later, and the district court did properly certify its judgment for appeal under Federal Rule of Civil Procedure 54(b). On the merits, we conclude that Saks cannot mount any of its desired defenses: It waived its right to present affirmative defenses to liability in the

1 The company originally known as Saks Holdings, Inc., merged with Proffitt’s, Inc., in 1998 to form Saks Inc. Saks Inc. then changed its name to SFA Holdings during this litigation. We refer to the entity as “Saks” throughout this opinion. No. 23-1489 3 guaranty that it signed. We therefore affirm the district court’s judgment. I At the heart of this dispute is a rental contract between CPS and WEC that Saks guaranteed. In 1985, CPS signed a lease with WEC to operate a Carson Pirie Scott Department Store at the Stratford Square Mall in Bloomingdale, Illinois. Under the lease terms, CPS agreed to pay WEC rent in monthly installments plus a penalty on any overdue rent. The parties agreed that the penalty would amount to a rate of interest equal to the lesser of: (a) the maximum amount of interest permitted under applicable state law, or (b) the greater of (i) four percent (4%) in excess of the yield, from time to time, as quoted daily in the Wall Street Journal (or if the same is not then published, another similar national journal selected by Landlord), of U.S. Treasury Bonds having an maturity clos- est to that date which is ten (10) years after the date of the Event of Default, or (ii) sixtee