** Shares of AI infrastructure firm Nebius Group NBIS.O down 5% to $90.94 premarket as it looks to raise capital

** NBIS shares on Tues finished up ~49% at $95.72 after co said it will supply Microsoft MSFT.O GPU infrastructure capacity in $17.4 bln deal over a 5-yr period

** Nebius early Weds commences $1 bln stock offering with Goldman Sachs as lead bookrunner, joined by Morgan Stanley, BofA and Citigroup

** It also announces private offerings of $2 bln convertible bonds, split equally between 5-yr and 7-yr tenors

** Co intends to use net proceeds from the transactions to grow its business, including acquiring additional compute power and hardware, among other uses

** With ~238.7 mln shares outstanding, Nebius has about $23 bln market cap, per LSEG data

** Through Tues close, shares gained ~245% YTD

(Lance Tupper is a Reuters market analyst. The views expressed are his own)

((lance.tupper@tr.com 1-646-279-6380))