** EV maker Rivian's RIVN.O shares down 4.5% premarket on Weds to $15.75 after $1.2 bln follow-on priced

** RIVN late Tues sold 75 mln shares at $15.50, a 6% discount to last close

** Stock shed 18% on Tues after it launched offering to fund equity contributions as part of a loan agreement with the U.S. Department of Energy

** Goldman Sachs, Allen & Co, Barclays, JP Morgan, Morgan Stanley and Wells Fargo jt bookrunners for offering

** Irvine, California-based RIVN has ~1.4 bln shares outstanding for roughly $22.4 bln market cap

** Last week, RIVN raised 2026 delivery forecast, betting on strong demand, including for its smaller, more affordable R2 SUVs

** Through Tues RIVN stock down 16% YTD vs 11% advance in Nasdaq .IXIC

** Avg rating of 27 analysts is "hold"; median PT $18, per LSEG data