Jobs are at risk at eleven Arcadia stores in Sussex after ASOS agreed to buy Topshop, Topman and Miss Selfridge - but not the 70 UK stores, employing 2,500 people.
Employees face an uncertain future after the online retailer excluded the stores from its £330m offer for the brands.
The deal, including leisurewear brand HIIT, is expected to be completed later this week.
ASOS told Sky News:
"These are strong brands that resonate well with our core customer base."
The move follows the collapse of Sir Philip Green's Arcadia retail empire late last year.
According to Sky News, around 300 employees will transfer to the new owners but it spells a bleak future for those working in the stores, which are all expected to close permanently.
ASOS Chief executive Nick Beighton told Sky News:
"We are extremely proud to be the new owners of the Topshop, Topman, Miss Selfridge and HIIT brands.
"The acquisition of these iconic British brands is a hugely exciting moment for ASOS and our customers and will help accelerate our multi-brand platform strategy."
Stores in Sussex:
Topshop Brighton at Churchill Square Shopping Centre
Topman Brighton at Churchill Square Shopping Centre
Topshop Eastbourne at The Beacon
Topman Eastbourne at The Beacon
Topshop Worthing in Montague Street
Topman Worthing in Montague Street
Topshop Chichester in East Street
Topman Chichester in East Street
Topshop Crawley at The Martletts
Topman Crawley at The Martletts
Miss Selfridge Crawley at County Mall
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