Fashion brand Anne Klein no longer has its own e-commerce site. Retailer Hot Topic has lost its crown jewel. Nine West Holdings, a collection of retail brands, has been stripped of valuable parts.

Doing much better is the owner of these once-popular brands, Sycamore Partners, which has managed to succeed where many others have failed. It has made hundreds of millions of dollars in the struggling retail sector by investing in brick-and-mortar chains.

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