FRANKFURT (Reuters) - Laboratory services group Synlab on Monday guided investors to expect its planned initial public offering to price at the bottom of the marketing range, cutting the offer size by a quarter due to sluggish demand. The company is now offering new shares worth 400 million euros ($484 million) plus existing shares worth 271 million euros at 18 euros apiece, excluding an overallotment option, the bookrunners organising the deal said. That is down from an original base deal size of 895 million to 1.03 billion euros. The deal will give Synlab, which had offered its shares in a range of 18 euros to 23 euros, a market capitalisation of 4 billion euros. Its free float will stand at 17%. Existing shareholders including Cinven, Novo Holdings and the Ontario Teachers’ Pension Plan Board decided to cut their shares on offer, having hoped for a higher valuation and to ensure a good market performance after the listing, one of the bookrunners said. Investors had questioned the sustainability of earnings, which had spiked 71% to 679 million euros in 2020 on the back of strong demand for Synlab’s COVID-19 testing capacities. According to Fitch, about a fifth of Synlab’s sales are COVID-19 related, a positive factor that the ratings agency expects will still be relevant until 2023, albeit likely on a smaller scale. Synlab is forecasting sales to exceed 3 billion euros in 2021, compared to 2.6 billion in 2020. It projects 10% annual revenue growth over the longer term, of which 3% will be organic with the rest driven by acquisitions. Books for Synlab’s IPO close on Tuesday with the first trading day slated for April 30.