Shares of Oscar Health Inc. /zigman2/quotes/225116571/composite OSCR -2.56% didn't pick a great day to go public, as the stock opened 7.7% above the initial public offering price despite better-than-expected pre-open investor demand. The digital health-insurance company offered 37 million shares in the upsized IPO, which priced at $39 each, above the recently raised expected range of between $36 and $38 a share. The pricing valued the company at about $7.69 billion. The stock's first trade was at $36.00 at 12:15 p.m. Eastern for 2.5 million shares. The stock has since pared some losses to trade down 6.7% at $36.17, while trading in a range of $35.00 to $36.77. Oscar Health went public on a day that the Renaissance IPO ETF /zigman2/quotes/207665280/composite IPO -1.65% was shedding 3.3% while the S&P 500 /zigman2/quotes/210599714/realtime SPX -0.20% fell 0.4%.