** Shares of PTC Therapeutics PTCT.O up 5.5% before the bell to new record high $84.20 ahead of S&P SmallCap 600 .SPCY inclusion this week
** PTCT will replace SanDisk SNDK.O prior to market open on Fri, per the S&P Dow Jones Indices
** Data storage firm SNDK moving to S&P 500 .SPX, replacing Interpublic Group IPG.N
** IPG being acquired by ad giant Omnicom OMC.N in about $13 bln deal slated to close on Weds after the bell
** Stephens analyst Melissa Roberts estimates passive funds will need to purchase 10.8 mln PTCT shares, which implies 9 days of buying demand
** Warren, New Jersey-based PTCT has ~80.3 mln shares outstanding for $6.4 bln market cap
** Co focused on developing treatments for rare disorders including Duchenne muscular dystrophy, Friedreich's ataxia and Huntington's disease
** Through Mon close, PTCT shares up 77% YTD. Stock hit record intraday high of $81.16 during the session
** Avg rating among 16 brokerages is "buy"; median PT of $80 up from $63 a month ago, per LSEG data
(Lance Tupper is a Reuters market analyst. The views expressed are his own)
((lance.tupper@tr.com 1-646-279-6380))